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Effect of drought length on the performance of cabbage (Brassica oleracea var capitata) in the forest-savannah transition zone, Ghana

Effect of drought length on the performance of cabbage (Brassica oleracea var capitata) in the... Plant Physiol. Rep. (January–March 2021) 26(1):74–83 https://doi.org/10.1007/s40502-020-00541-5 O R I G IN AL ARTI CL E Effect of drought length on the performance of cabbage (Brassica oleracea var capitata) in the forest-savannah transition zone, Ghana 1 2 E. Ackah R. Kotei Received: 6 February 2020 / Accepted: 22 September 2020 / Published online: 7 November 2020 The Author(s) 2020 Abstract The drought tolerance of Cabbage, Brassica transition zone, the initial and development stages could oleracea var capitata (Oxylus) was investigated by sub- tolerate drought stress up to 5 days whilst the mid stage jecting the initial, development and mid growth stages to could tolerate up to 7 days. varying drought lengths of 5, 7, 9, 11, 13 and 15 days in a 7 9 3 factorial experiment to determine the effect of each Keywords Oxylus  Drought  Brassica oleracea  Growth drought period at each growth stage on growth and yield. stages  Chlorophyll  Forest-savannah  Yield Data on number of opened leaves/plant, leaf area index (LAI), leaf chlorophyll content, head size and yield/ha were recorded due to drought effect at each growth stage. Introduction Analysis of variance at 5% probability level indicated that drought periods of 5–15 days at the initial stage signifi- Cabbage (Brassica oleracea L. var. capitata) is a veg- cantly reduced number of leaves, LAI and head size. Sig- etable crop grown worldwide including African countries nificant reduction in chlorophyll content and yield were (Grzywacz et al. 2010). It is widely adapted to the tropical due to drought beyond 11 and 5 days respectively at the climates (Blankson et al. 2013). In Ghana, cabbage pro- initial stage. Number of opened leaves increased signifi- duction is mostly popular among peri-urban and urban cantly with increasing drought length at the development dwellers in response to high demand (Timbilla and Nyarko stage; critical at 11 days drought. Significant reductions in 2004). Cabbage is also grown in cities and rural commu- LAI at the development and mid stages were critical at 11 nities in Ghana and it serves as an important source of and 9 days respectively whilst chlorophyll content was livelihood for many smallholder farmers in Ghana (Bai- significantly reduced at both the development and mid phethi and Jacobs 2009). stages by all drought periods. Significant reduction in head The world’s annual production of cabbage is around size at the development and mid stages was critical at 70,644,191 tons with an average yield of about 29.23 ton/ 7 days. Generally, the drought tolerance of cabbage ha (Kidane 2016). The major production constraints mostly increased from the initial to the mid-stage. To maintain reported in Ghana are insect pests, diseases, the need for economic yields of cabbage in the forest-savannah high fertilizer input and the high cost of pesticides (Wil- liamson et al. 2008). The changing patterns of climatic parameters like tem- perature and precipitation are emerging major threats for & E. Ackah bigemma1995@gmail.com vegetable production in the forest-savannah transition zone (Challinor et al. 2014). The effect of water stress is Department of Crop and Soil Science, College of Agriculture expected to increase with increasing length of drought. An Education, University of Education, Winneba, anticipated report revealed that up to 30% of the yields Mampong-Ashanti, Ghana from rain-fed farming in some south Asian countries could Department of Agriculture Engineering and Mechanization, be lost to increasing drought stress by 2050 (Intergovern- College of Agriculture Education, University of Education, mental Panel on Climate Change [IPCC], 2007). Though Winneba, Mampong-Ashanti, Ghana 123 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 75 cabbage production in the forest-savannah transition envi- an average annual rainfall of 1270 mm and two rainy ronment of Ghana is lucrative during the dry season seasons. The major rainy season starts in March and ends in (November to February), inadequate water availability August whilst the minor is between September and limits production (Ezeaku et al. 2014). November. The remaining months spans the harmattan Rise in temperature as well as increasing drought fre- (dry) season. The average annual temperature is 27 C with quency and length at any stage of crop growth can affect variations in mean monthly temperature ranging between the normal growth, flowering, pollination, fruit develop- 22 and 30 C (Kotei et al. 2015). ment and subsequently decrease crop yield (Hedhly et al. 2009). Changes in chlorophyll content are often measured Experimental design and drought application as a symptom of water stress (Majumdar et al. 1991). Cabbage has been classified as moderately susceptible to The experiment was a 7 9 3 factorial in a Randomized water stress, with the head formation period being more Complete Block Design (RCBD). The factors included sensitive (Shannon and Grieve 1998). Maggio et al. (2005) drought length with seven (7) treatments and three (3) reported that drought stress decreased the total head yield growth stages, each replicated thrice (3). The growth of cabbage from 50.5 to 17.5 tons/ha without stating the stages, including ‘‘initial/vegetative growth stage, devel- length or duration. In Brassica napus cultivars, water stress opment/head formation stage and mid/head filling stage’’ reduced chlorophyll a ? b content by 38% compared with were subjected to 5, 7, 9, 11, 13 and 15 days of complete the adequately watered plants (Paclik et al. 1996). drought. A control treatment (0 days drought) which The Forest-Savannah Transition Zone is known to received water continuously throughout the experimental experience drought spells even in the main rainy seasons period was set aside for the experiment. Seeds for the varying from 1 to 3 weeks. For this reason, farmers who research (Oxylus variety) were obtained from a certified depend mostly on rain are usually faced with the challenge Agro-Chemical shop and seedlings raised under conducive of selecting a suitable planting date for their seasonal nursery conditions for three (3) weeks and before trans- crops. Cabbage production in the Forest-Savannah Tran- planting. To avoid transplanting shock, all transplants were sition Zone thus experiences increasing frequency and watered for 4 days before drought application. The appli- length of drought which is bound to occur at any of the cation of drought however ended in March, 2018 while growth stages of the crop. Although several studies confirm experimental plants continued through the ‘‘late growth the significant effect that drought stress can depict on stage’’ in April, 2018. cabbage production, none of these studies indicated how Water supply to plants was completely based on how the long, within a particular growth stage, will the effect of drought periods were imposed and a well scheduled drip drought manifest. This study therefore sought to unveil the irrigation system. Water requirements were estimated using critical length of drought occurrence (in days) at the growth monthly Reference Evapotranspiration (ETo) obtained stages of cabbage from which growth and yield will be from Mampong Meteorological Agency (MMA) and Crop significantly affected. coefficient (Kc) of growth stages of the crop, according to FAO (2018) were used in computing various parameters for calibrating the drip system. Materials and methods The experimental field comprised of three main blocks representing the three growth stages with each measuring The study area 11 m 9 12.6 m with 1 m path from each. Each main block (growth stage) was further divided into six sub blocks, This study was conducted at the College of Agriculture representing 6 drought periods (5, 7, 9, 11, 13 and 15 days Education, University of Education, Winneba, the Mam- droughts) each measuring 2 m 9 12.6 m with a 1 m path pong campus during the dry season between December, from each other. Each sub block was further divided into 2017 and April, 2018. Mampong-Ashanti lies North of three plots, measuring 2 m 9 4.2 m with a 1 m path Kumasi within the Forest-Savannah Transition Zone between plots. The control treatment (0 days drought) between the Guinea Savanna in the North and Forest region comprised of a single block (2 m 9 12.6) divided into of the South of Ghana, and lies between longitudes three plots (2 m 9 4.2 m each). Each treatment plot hosted 0 00 0 00 0 00 0000 05 Wto1000 30 W and latitudes 6000 55 Nto 24 plants resulting in a total of 1368 experimental plants, 0 00 7000 30 N of the equator. The Mampong Municipality including the control. lies within the Wet Semi-Equatorial Forest Zone. Due to human activities like charcoal production, lumbering and bush fires, the forest vegetation, particularly the North- Eastern part, has been reduced to Savannah. The area has 123 76 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 Calibration of the drip system Table 2 Kcs for the growth stages of Brassica Oleracea. Source: FAO (2018) Twenty (20) containers were used to collect water ran- Crop stage Initial Development Mid Late domly from emitters scattered between the first and last Kc 0.4 0.7 0.95 0.9 dripping points in 15 min and the average volume of water was determined to be 150 mL = 0.15 L. Dripping rate of the system was estimated using Eq. 1. 0:15 L min Drip per minute ¼ ¼ 0:01 L ð1Þ coefficient (UC) and emission uniformity (EU) using dis- 15 min charge measurement data from 20 emitters. The uniformity coefficient equation according to Dudek and Fernandez Crop evapotranspiration (ETc)/water requirement (2015) and the emission uniformity equation were employed to compute the uniformity parameters of the drip The crop evapotranspiration (ETc) for the growth stages system. These equations are simple and are widely used in representing the water requirement of each particular stage the present days (Al-Ghobari, 2012; Asif et al. 2015): were estimated using Eq. 2. SD Uniformity coefficientðÞ UC ¼ 100 1  ð5Þ day ETc mm ¼ Mean monthly ETo  Kc ð2Þ rffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi Mean monthly ETos for the four (4) months period of SD ¼ jj q  q ð6Þ the study and Kcs for the growth stages of cabbage are presented in Tables 1 and 2 respectively. alq Emission uniformityðÞ EU ¼  100 ð7Þ Irrigation time Coefficient of variation (CV ) In order to match the estimated ETc with the dripping rate -min (L ), ETc for each growth stage was converted from According to Asif et al. (2015), the coefficient of variation -day -day L to mm . is generally used as a measure of emitter flow variation due -day -day By conversion, 4.1 mm = 0.3 L (Arku et al. to variation in manufacturing characteristics of the emis- 2012). sion devices. The CV describes the quality of the material Hence, and processes used to manufacture the emission devices. It is determined from flow measurements for several identical ETcðÞ mm/day 0:3 L/day day Converted ETc L ¼ ð3Þ emission devices and is computed using Eq. 8. 4:1 mm/day SD Time to run the system in minutes per day was estimated CV ¼ ð8Þ using Eq. 4. where q = discharge of emitter i, q = overall average of Converted ETcðÞ L/day Irrigation time ¼ ð4Þ emitter discharges, n = number of emitters, q = average alq Dripping rateðÞ L/min low/min-quarter emitter discharge, SD = standard devia- Estimated time for running the irrigation system during tion, CV = manufacturers’ coefficient of variation for the growth periods are presented in Table 3. emitters. Evaluation of the drip system Emission uniformity rating The drip irrigation system used in the study was evaluated Dudek and Fernandez (2015) rated emission uniformity of its delivery efficiency by estimating its uniformity values as follows: \77% ¼ Very poor 77  82 ¼ Poor 83  90% ¼ Acceptable [ 90% ¼ Excellent Table 1 Monthly ETo for study area. Source: Meteorological Service Department, Mampong agency The emission coefficient (EU), 97.07% estimated from Month Jan Feb Mar Apr the catch results collected in this study indicates that the -day drip system used for water application was highly efficient ETo (mm ) 4.94 5.39 4.63 3.86 with only 2.93% water loss. The uniformity coefficient (UC) and CV values were 95.68% and 0.043 respectively. 123 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 77 Table 3 Estimated times for running the irrigation system Stage (days) Month/period ETo Kc ETc Converted ETc Dripping rate (L/ Time (days) (mm/day) (mm/day) (L/day) min) (min/day) Initial (20 days) Jan—20 4.94 0.40 1.98 0.14 0.01 14 Development Jan—4 4.94 0.70 3.46 0.25 0.01 25 (30 days) Feb—26 5.37 0.70 3.76 0.28 0.01 28 Mid (20 days) Feb—2 5.37 0.95 5.10 0.37 0.01 37 Mar—18 4.63 0.95 4.40 0.32 0.01 32 Late (20 days) Mar—12 4.63 0.90 4.17 0.30 0.01 30 Apr—8 3.86 0.90 3.47 0.25 0.01 25 According to Asif et al. (2015), the ranges of Cv values and Yield and yield components their appropriate interpretations are as follows: Cabbage heads were harvested at the end of the ‘‘late [ 0:4 ¼ Unacceptable 0:40:3 ¼ Low growth stage’’ when heads were fully filled and thus, felt 0:30:2 ¼ Acceptable 0:2  0:1 ¼ Very good hard when squeezed. Head size/girth and weight were \0:1 ¼ Excellent measured with fiber glass tape and electronic scale Thus, the UC and CV values estimated from the catch respectively. Head weights were used to estimate yield data show high efficiency of the drip system. (tons/ha). Growth and physiological measurements Statistical analysis Number of opened leaves, leaf area index (LAI) and Data on growth parameters including number of opened chlorophyll content index were measured on 9 plants from leaves, LAI and leaf chlorophyll content index were sub- each replicate at the end of each growth stage. Normal jected to a one-way analysis of variance analysis irrigation resumed after each drought treatment. For the (ANOVA) with drought length as the varying factor for initial stage, the leaves of selected plants were counted and each growth stage whilst data on head size and yield were the average estimated to represent the number of leaves of subjected to two-way analysis of variance with drought a single plant before head formation. For the development length and growth stage as varying factors using Genstat and mid stages, the outer leaves were counted and the statistical package windows version 11.1 (2008). This average estimated at the end of the stages. analytical strategy was employed owing to physiological The leaf area of selected crops was measured indirectly differences of the crop at the different growth stages which using Imagej software version 1.46r (Scurlock et al. 2001). could result in biased growth at the stages. As a result, The selected leaves were captured at equal height above comparing growth at the stages may be unfair; however, ground level. The images were then cropped in adobe the resultant effect of drought at the different growth stages Photoshop CS6 to obtain the actual area of the canopy, on yield parameters are fairly comparable. Where signifi- excluding parts of the ground which appeared in the orig- cant differences existed, mean separation was done using inal image. The resultant image was transported into the the LSD criterion at 5% (0.05) probability level. imagej where the area of the canopy was estimated. The area of land occupied by the selected plants was also estimated. Leaf area index was then calculated as Results canopy area (Scurlock et al. 2001). ground area Number of opened leaves/plant Leaf chlorophyll content index was measured using the Chlorophyll meter (CCM-200 Plus). The leaf chlorophyll With increasing drought length, number of opened leaves content index estimates were taken 3 times from six fully decreased at the initial stage, increased at the development expanded leaves, two (2) leaves each from the bottom set, stage but remained constant during the mid-stage. Analysis middle set and upper set of leaves of selected plants. The of variance of results (Table 4), indicated significant (P average chlorophyll content was estimated in CCI. B 0.05) reduction in number of leaves at the initial stage 123 78 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 Table 4 Mean number of Growth stage Drought length (days) LSD CV(%) opened leaves as influenced by drought length at different 0 5 7 9 11 13 15 growth stages of B. oleracea var a b b b b b b capitata Initial 13 11 10 10 10 10 10 1.4 7.6 a a a a b ab ab Development 19 19 19 19 22 21 21 2.0 5.7 Mid 20 20 20 20 20 20 20 1.2 ns 3.3 Between column means bearing different superscripts differ significantly (P B 0.05) due to all drought periods (5–15 days) compared to the LAI under 9, 11, 13 and 15 days of droughts respectively control. The control plants produced the highest number of as compared to the control. leaves (13), preceded by 5 days drought stressed plants (11 Leaf chlorophyll content index (CCI) leaves) whilst the rest of the drought periods, although similar in their effects on number of leaves at the initial stage, each resulted in 23.1% reduction in number of Leaf chlorophyll content index generally decreased as leaves. At the end of the development stage, number of drought length advanced regardless of growth stage opened leaves significantly (P B 0.05) increased from 19 (Table 6). Leaf chlorophyll content was significantly (P to 22 leaves under 11 days drought and to 21 leaves under B 0.05) decreased under 13 and 15 days drought occurring 13 and 15 days droughts but 5–9 days drought periods had at the initial stage (12.96% and 15.91% respectively) no significant (P [ 0.05) effect on number of opened compared to the control. At the development stage, leaf leaves at the development stage. At the mid-stage, drought chlorophyll content index was significantly (P B 0.05) length had no significant (P [ 0.05) effect on number of reduced under each of the applied drought periods com- opened leaves (Table 4). pared to the control. Significant reductions of 11.8%, 15.1%, 17%, 17.9%, 49.7% and 48.9% were due to 5, 7, 9, Leaf area index (LAI) 11, 13 and 15 days drought respectively. Similar to the development stage, chlorophyll content index of cabbage Results indicate that as drought length increased LAI leaf at the mid-stage was significantly (P B 0.05) reduced decreased at all growth stages (Table 5). Analysis of by all applied drought periods compared to the control. variance indicated that LAI at the initial stage was signif- Significant reductions of 10.8%, 12.9%, 12.7% and 48.9% icantly (P B 0.05) highest for the control (0.013) and were due to 5, 7, 9 and 15 days droughts respectively lowest (0.005) for 15 days drought stressed plants. Plants whilst 11 and 13 days droughts reduced leaf chlorophyll subjected to 5, 11, 13 and 15 days droughts at the initial content by 17.2% at the mid-stage. stage were significantly reduced of their LAI by 30.8%, 53.8%, 46.2% and 61.5% respectively whilst 7 and 9 days Head size/girdle at harvest (cm) droughts significantly reduced LAI at the initial stage by 30.5% compared to the control. LAI at the development Head size, when compared across the growth stages gen- stage was significantly (P B 0.05) reduced only under erally increased from the initial stage to the mid-stage 15 days drought. The control plants recorded the highest (initial \ development \ mid), indicating a decreasing LAI of 0.043 followed by 5 days drought (0.039) with effect of the same drought period on head size as the crop 15 days drought stressed plants recording the significantly advances from one stage to another, with head size at the (P B 0.05) lowest (0.033) which was 23.3% lower than initial stage being significantly (P B 0.05) lowest that of the control plants. At the mid-stage, significant (57.56 cm) compared to the development and mid stages reductions of 18.6%, 25.6%, 30.2% and 37.2% occurred in (61.47 cm and 61.96 cm respectively) (Table 7). Table 5 Mean LAI as Growth stage Drought length (days) LSD CV (%) influenced by drought length at different growth stages of B. 0 57911 13 15 oleracea var capitata a b bc bc c b c Initial 0.013 0.009 0.008 0.008 0.006 0.007 0.005 0.002 15.5 a a a a b ab ab Development 0.043 0.039 0.039 0.039 0.035 0.034 0.033 0.009 13.8 a ab ab bc cd cd d Mid 0.043 0.039 0.038 0.035 0.032 0.030 0.027 0.005 8.7 Between column means bearing different superscripts differ significantly (P B 0.05) 123 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 79 Table 6 Mean leaf chlorophyll Growth stage Drought length (days) LSD CV (%) content index (CCI) as influenced by drought length at 0 5 7 9 11 13 15 different growth stages of B. a a a a ab b b oleracea var capitata Initial 80.35 78.16 79.27 78.98 72.27 69.90 67.57 5.986 4.5 a b b b b c c Development 80.35 70.86 68.21 66.66 66.00 40.45 41.07 2.407 4.8 a b b bc bc c c Mid 80.35 72.83 71.64 70.00 70.18 66.49 66.51 4.712 3.7 Between column means bearing different superscripts differ significantly (P B 0.05) Generally, head size due to drought length within a Nine (9) and 15 days drought differed significantly (P particular growth stage significantly (P B 0.05) decreased B 0.05) in terms of yield but both statistically similar with increasing drought length from 66.46 cm without (P [ 0.05) to 11 and 13 days droughts. Interactively (drought length * growth stage), five (5) drought to 54.88 cm under 15 days drought. Significant reductions of 3.64%, 9.04%, 10.53%, 10.79%, 13.17% and days drought at any of the growth stages and 7 days 17.42% were due to 5, 7, 9, 11, 13 and 15 days of drought drought at the development and mid stages had no signif- compared to the control. icant (P [ 0.05) effect on final yield compared to the Interacting growth stage with drought length indicated control. Drought beyond 5 days at the initial stage and that all applied drought periods at the initial stage signifi- drought beyond 7 days at the development and mid stages cantly (P B 0.05) decreased final head size as compared to significantly (P B 0.05) decreased yield compared to the the control. All but 5 days drought occurring at the control. The control plants produced a maximum yield of development and mid stages significantly (P B 0.05) 52.59 tons/ha which was 53.4% higher than the minimum decreased final head size as compared to the control. yield of 24.5 tons/ha produced by plants subjected to Overall, the minimum head size (52.88 cm) was recorded 15 days drought during the initial stage. Subjecting the under 15 days drought occurring at the initial stage which initial stage to 7, 9, 11 and 13 days drought resulted in was 20.4% lower than that of the control. Seven (7) days significant yield reductions of 22%, 44.2%, 45.2% and drought occurring at the initial, development and mid 48.3% respectively compared to the control. Nine (9), 11, stages significantly decreased final head size by 11.7%, 13 and 15 days droughts at the development stage caused 7.9% and 7.5% respectively. Nine (9) days drought at the 34.0%, 36.9%, 43.9% and 47.8% significant yield reduc- initial, development and mid stages decreased head size by tions respectively whereas 9, 11, 13 and 15 days droughts 17.1%, 7.6% and 6.8% whilst 11 days drought had 18.2%, at the mid stage decreased yield by 21.0%, 25.0%, 22.7% 7.3% and 6.9% significant reductions respectively com- and 24.6% respectively compared to the control. pared to the control. 13 days drought resulted in 19.5%, 10.3% and 9.7% whilst 15 days drought at the respective Measured parameters and their critical length growth stages decreased final head size by 20.4%, 16.7% of drought (days) and 15.1% compared to the control. Critical drought length from which the measured parame- Yield (tons/ha) ters started experiencing significant reduction are presented in Table 8. Drought duration of 5 days and beyond at the Similar to head size, yield of cabbage generally increased initial stage were critical for number of opened leaves, LAI across the growth stages from initial to mid for each and head size whereas 13 and 7 days length of drought at drought period (initial \ development \ mid) (Table 7). the initial stage were critical against chlorophyll content Yield of cabbage differed significantly amongst the three index and yield respectively. At the development stage, growth stages with the yield due to drought at the initial 11 days drought was critical against number of opened stage (36.25 tons/ha) being the significantly (P B 0.05) leaves and LAI, 5 days was critical against chlorophyll lowest compared to those at the development (39.10 tons/ content index whilst 7 days was critical against both yield ha) and mid stages (44.56 tons/ha). components. At the mid stage, number of opened leaves Yield also decreased with increasing drought within a was not affected by drought length. However, 9 days particular stage. Five (5) days drought had no significant drought at the mid stage was critical against LAI and yield (P [ 0.05) effect on yield whilst the rest of the applied whereas 5 and 7 days drought were critical for chlorophyll drought periods significantly (P B 0.05) reduced yield content index and head size respectively. compared to the control. Five (5) and 7 days drought periods differed significantly (P B 0.05) from the rest. 123 80 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 Table 7 Effect of Drought Length at different growth stages of B. Discussion oleracea var capitata on final head size/girth (cm) and yield (tons/ha) Number of opened leaves/plant Treatment Head size/girth (cm) Yield (tons/ha) Growth stage Lesser leave numbers at the initial stage might be due to a a Initial (I) 57.56 36.25 decreased leaf formation and growth. Increased number of b b Development (D) 61.47 39.10 opened leaves at the development stage is attributable to b c Mid (M) 61.96 44.56 delayed cupping due to drought stress. At the mid-stage LSD (0.05) 1.553 2.398 however, heads had already formed and drought stress Drought length (days) would have no effect on the number of outer leaves. a a 0 66.46 52.59 Decreasing number of leaves at the initial stage was critical b a 5 64.04 50.99 even under 5 days drought whereas an increase in the c b 7 60.45 44.19 number of opened leaves due to delayed cupping at the c c 9 59.46 35.20 development stage was critical under 11 days drought c cd 11 59.29 33.83 (Table 8). Lalinia et al. (2012) reported that drought stress c cd 13 57.71 32.44 at the flowering stage decreased number of branches in d d 15 54.88 30.54 mungbean. Gupta et al. (1995) also reported reduced LSD (0.05) 2.372 3.664 number of branches in chickpea when drought was Interactions imposed at the early flowering stage. In the present study, a a 0*I 66.46 52.59 the initial stage of B. oleracea var capitata appeared to be a a 0*D 66.46 52.59 most sensitive to increasing drought length than the a a 0*M 66.46 52.59 development and mid stages in terms of leave number. bc ab 5*I 61.94 50.26 According to Kabiri et al. (2014), drought stress at the abd ab vegetative stage is of less importance than at the repro- 5*D 64.67 50.98 ab a ductive stage of tension with regards to impact on yield and 5*M 65.50 51.72 ce bd yield components. However, drought stress at the vegeta- 7*I 58.67 41.04 cd bd tive stage impacts leaf and stem development, photosyn- 7*D 61.20 45.24 bc ab thesis, and the accumulation of important plants 7*M 61.49 46.30 ef cf components (Fathi and Tari 2016). The biophysical factors 9*I 55.10 29.37 cd ce mostly affected are the size and number of leaves in plants 9*D 61.38 34.69 bc bd (Ghodsi et al. 1998). 9*M 61.91 41.56 f cf 11*I 54.36 28.83 bc cef Leaf area index (LAI) 11*D 61.64 33.20 bc de 11*M 61.88 39.46 f f Restriction on leaf area is the first line of defense against 13*I 53.50 27.19 water stress. Similar to number of leaves, the initial stage ce cf 13*D 59.59 29.50 was most sensitive to increasing drought in terms of LAI as c bd 13*M 60.03 40.63 reduction in LAI at this stage was observed under 5 days f f 15*I 52.88 24.50 drought and beyond. Whereas at the development and mid ef f 15*D 55.33 27.46 stages critical drought periods were 11 and 9 days ef de 15*M 56.43 39.67 respectively (Table 8). Reduced LAI at the various growth LSD (0.05) 4.109 6.346 stages were due to already mentioned factors that resulted CV % 4.1 9.6 in the decrease in the number and size of opened leaves. Between column means bearing different superscripts differ signifi- LAI results from this study are in agreement with that of cantly (P B 0.05) Rao and Bhatt (1988) who reported reduction in leaf area of Capsicum annum L. to drought stress at all the growth stages, viz., vegetative, flowering and fruiting. Leaf Chlorophyll content index (CCI) Decrease in leaf chlorophyll content index due to drought stress is considered a typical symptom of pigment photo 123 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 81 Table 8 Measured parameters and their critical length of drought (days) at different growth stages Growth stage Parameter Number of opened leaves LAI Chlorophyll content index (CCI) Head size (Cm) Yield (tons/ha) Initial 5 5 13 5 7 Development 11 11 5 7 7 Mid ns 9 5 7 9 ns non-significant oxidation and chlorophyll degradation (Anjum et al. 2011). which led to increased number of opened leaves (Table 4, A decrease in total chlorophyll content index with development stage), especially under 11–15 days drought. increasing drought stress implies a lowered capacity for During this stage, leaves are expected to form heads but light harvesting. Since the production of reactive oxygen became flaccid under lengthy water stress and as a result species mainly depends on excess energy absorption in the remained opened around the head. Also, leaf senescence photosynthetic apparatus, this might be avoided by after rapid vegetative growth led to reduced amount of leaf degrading the absorbing pigments (Mafakheri et al. 2010). chlorophyll which consequently reduced tissue formation In relation to chloroplastic protein hydrolysis and thereby reducing leave sizes at the mid stage. According to decreasing leaf pigments (Sgherri et al. 1993), it could be Xu and Leskovar (2014), even 50% and 75% deficit irri- expressed that drought effect on chlorophyll in leaf due to gation applied before and after head formation of cabbage drought is a primary stage in degradation of proteins. Also, significantly decreased final head size. They also reported the decrease in chlorophyll under drought stress might be significant reduction in head size under 50% deficit irri- as a result of reduced synthesis of the main chlorophyll gation applied to the head formation stage. Interacting pigment complexes encoded by the cab gene family (Al- growth stage with drought length indicated reduced head lakhverdiev et al. 2000). Decreased chlorophyll content size even under 5 days drought at the initial stage whereas may also be attributed to reduced dry matter production as at the development and mid stages this was critical at a result of reduced leaf photosynthesis. This effect is in 5 days drought. agreement with the findings of Premachandra et al. (1991) who reported 67–97% lower leaf photosynthesis in stressed Yield (tons/ha) maize plants than in watered plants. Critical drought peri- ods for chlorophyll reduction were observed under 13 days Generally, yield reduction was greater when the initial drought at the initial stage whereas even 5 days drought at stage was subjected to drought irrespective of the length. the development and mid stages led to chlorophyll reduc- Also yield reduction was observed even under 7 days tion, indicating that the development and mid stages were drought at the initial and development stages whereas at the most sensitive to increasing drought in terms of chlorophyll mid stage yield reduction was critical under 9 days content. drought. Water stress during the initial stage reduces yield by reducing leave number and sizes or area while drought Head size/girdle at harvest (cm) stress at the development stage reduces yield by decreasing the number of leaves that entered into the head. Drought Final head size was influenced by the number of leaves, stress at the mid stage however reduces yield by reducing leaf area and the amount of energy intercepted throughout the plant of its moisture content which subsequently the growth period. Lower values of head size due to decreased head weight. Decrease in chlorophyll content at drought effect at the initial stage may be as a result of any stage also affects the formation of new tissues which decreased leaf formation potential indicated as reduced consequently decrease the final head weight. According to leave numbers and sizes. Although decrease in amount of MoFA average yields of 30–40 tons/ha are normal. FAO chlorophyll at the initial stage under short and moderate (2018) also stated that a maximum of about 50 tons/ha can droughts were not significant, consequences on growth be obtained when sprayed and well-fertilized. Under ideal significantly affected leaf numbers and sizes which sub- climatic conditions and good irrigation and crop manage- sequently reduced head size at maturity. Decreased head ment, yields can be as high as 85 tons/ha (FAO 2018). sizes due to drought period beyond 5 days at the devel- Moradi et al. (2008) reported that drought stress at the opment stage may be as a result of the delayed cupping 123 82 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 vegetative and reproductive stages reduced mungbean seed References yield by 9 and 49% respectively. Al-Ghobari, H. M. (2012). A comparison of water application uniformity for drip irrigation system above and below soil surface at various soil depths and scheduling techniques in arid Conclusions region. WIT Transactions on Ecology and the Environment, 168, 311–322. Allakhverdiev, S. I., Sakamoto, A., Nishiyama, Y., & Murata, N. Significant changes in number of opened leaves at the (2000). Inactivation of photosystems I and II in response to initial and development stages were critical under 5 and osmotic stress in Synechococcus. Contribution of water channels. 11 days drought respectively. Reduction in LAI at the Plant Physiology, 122(4), 1201–1208. initial, development and mid stages were critical under 5, Anjum, S. A., Xie, X. Y., Wang, L. C., Saleem, M. F., Man, C., & Lei, W. (2011). Morphological, physiological and biochemical 11 and 9 days respectively. Chlorophyll content index was responses of plants to drought stress. African Journal of reduced under critical drought periods of 13 days at the Agricultural Research, 6(9), 2026–2032. initial stage and 5 days at both the development and mid Arku, A. Y., Musa, S. M., & Mofoke, A. L. E. (2012). Determination stages. Number of opened leaves was however not affected of water requirement and irrigation timing for Amaranthus hybridus in Maiduguri metropolis, north-eastern Nigeria. In by drought occurrence at the mid stage. Fourth international conference on sustainable irrigation (pp. Projected reduction effect of drought on head size at 279–289). harvest was critical under 5 days drought at the initial stage Asif, M., Ahmad, M., Mangrio, A. G., Akbar, G., & Memon, A. H. and 7 days drought at the development and mid stages. (2015). Design, evaluation and irrigation scheduling of drip irrigation system on citrus orchard. Pakistan Journal of Mete- Since yield reduction was critical under 7 days drought at orology, 12(23), 37–48. the initial and development stages as well as under 9 days Baiphethi, M. N., & Jacobs, P. T. (2009). The contribution of drought at the mid stage, it suggest that implementing subsistence farming to food security in South Africa. Agrekon, water application at regular intervals of 7 days at the initial 48(4), 459–482. Blankson, A. W., Gurr, G. M., Gitau, C. W., Nicol, H. I., Munyakazi, and development stages as well as 9 days at the mid stage L., & Stevenson, P. C. (2013). Tri-trophic insecticidal effects of could maintain economic yield although growth may be African plants against cabbage pests. PLoS ONE, 8(10), e78651. moderately suppressed. https://doi.org/10.1371/journal.pone.0078651. Challinor, A. J., Watson, J., Lobell, D. B., Howden, S. M., Smith, D. Acknowledgement The Authors thank the Meteorological Service R., & Chhetri, N. (2014). A meta-analysis of crop yield under Department, Mampong-Ashanti Agency for providing climate data climate change and adaptation. Nature Climate Change, 4(4), (ETos) for scheduling our irrigation system. Dudek, T. A., & Fernandez, R. T. (2015). Conducting a water application uniformity evaluation for an overhead sprinkler Author contributions RK conceived the original idea. Both Authors irrigation system in the nursery (p. 15). Consultado: Michigan contributed to the experimental designed. EA carried out the exper- State University Extension. iment, performed analytical computations and wrote the first draft of Ezeaku, I. E., Okechukwu, E. C., & Aba, C. (2014). Climate change the manuscript. RK supervised the project and commented on pre- effects on maize (Zea mays) production in Nigeria and strategies vious versions of the manuscript. Both Authors read and approved the for mitigation. Asian Journal of Science and Technology, 5, final manuscript for submission. 862–871. Food and Agriculture Organization (FAO). (2018). Crop description Compliance with ethical standards and climate|Cabbage. Available at: https://www.fao.org/land- water/databases-andsoftware/cropinformation/cabbage/en/. Conflict of interest The Authors declare that they have no conflict of Fathi, A., & Tari, D. (2016). Effect of drought stress and its interest. mechanism in plants. International Journal of Life Sciences, 10(1), 1–6. https://doi.org/10.3126/ijls.v10i1.14509. Ethical approval The studies involved in this article did not inclu- Ghodsi, M., Nazeri, M., & Zarea-Fizabady, A. (1998). The reaction of ded animals or human participants as objects of research. new cultivars and elite lines of spring wheat into drought stress. In Collection of abstract articles of 5th Iranian agronomy and Open Access This article is licensed under a Creative Commons plant breeding conference, Karaj, Iran (p. 252). Attribution 4.0 International License, which permits use, sharing, Grzywacz, D., Rossbach, A., Rauf, A., Russell, D. A., Srinivasan, R., adaptation, distribution and reproduction in any medium or format, as & Shelton, A. M. (2010). Current control methods for diamond- long as you give appropriate credit to the original author(s) and the back moth and other brassica insect pests and the prospects for source, provide a link to the Creative Commons licence, and indicate improved management with lepidopteran-resistant Bt veg- if changes were made. The images or other third party material in this etable brassicas in Asia and Africa. Crop Protection, 29(1), article are included in the article’s Creative Commons licence, unless 68–79. indicated otherwise in a credit line to the material. If material is not Gupta, S. N., Dahiya, B. S., Malik, B. P. S., & Bishnoi, N. R. (1995). included in the article’s Creative Commons licence and your intended Response of chickpea to water deficits and drought stress. use is not permitted by statutory regulation or exceeds the permitted Haryana Agriculture University Journal of Research, 25(1/2), use, you will need to obtain permission directly from the copyright 11–19. holder. To view a copy of this licence, visit http://creativecommons. org/licenses/by/4.0/. 123 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 83 Hedhly, A., Hormaza, J. I., & Herrero, M. (2009). Global warming Moradi, A., Ahmadi, A., & Hossein Zadeh, A. (2008). Agro- and sexual plant reproduction. Trends in Plant Science, 14(1), physiological responses of mung bean (cv. Partov) to severe and 30–36. moderate drought stress applied at vegetative and reproductive IPCC, 2007 Climate Change. (2007). Impacts, adaptation and growth stages. JWSS-Isfahan University of Technology, 12(45), vulnerability. In M. L. Parry, O. F. Canziani, J. P. Palutikof, P. 659–671. J. van der Linden, & C. E. Hanson (Eds.), Contribution of Paclik, R. L., & Sakova, C. V. (1996). Reaction of different cultivars working group II to the fourth assessment report of the of Brassica napussubsp. oleifera to water stress. Fytotechnicka- intergovernmental panel on climate change (p. 976). Cambridge, Rada, 1, 55–62. UK: Cambridge University Press. Premachandra, G. S., Saneoka, H., Kanaya, M., & Ogata, S. (1991). Kabiri, R., Nasibi, F., & Farahbakhsh, H. (2014). Effect of exogenous Cell membrane stability and leaf surface wax content as affected salicylic acid on some physiological parameters and alleviation by increasing water deficits in maize. Journal of experimental of drought stress in Nigella sativa plant under hydroponic botany, 42(2), 167–171. culture. Plant Protection Science, 50(1), 43–51. Rao, S., & Bhatt, R. M. (1988). Photosynthesis, transpiration, Kidane, D. (2016). Assessment of cabbage production practices and stomatal diffuse resistance, and relative water content of effect of NP fertilizer rate on head yield and yield components in capsicum (Bell Pepper) grown under water stress. Photosynthet- Lay Armacheho district. Doctoral dissertation, Bahir Dar ica (Praha), 22(3), 377–382. University. Scurlock, J. M. O., Asner, G. P., & Gower, S. T. (2001). Worldwide Kotei, R., Agyare, W. A., Kyei-Baffour, N., Frempong, N. K., & Atta- historical estimates of leaf area index, 1932–2000. ORNL/TM- Darkwa, T. (2015). Development of groundwater recharge model 2001/268, p. 34. for the sumanpa catchment at Ashanti-Mampong-Ashanti Area Sgherri, C. L. M., Pinzino, C., & Navari-Izzo, F. (1993). Chemical in Ghana. changes and O —production in thylakoid membranes under Lalinia, A. A., Hoseini, N. M., Galostian, M., Bahabadi, S. E., & water stress. Physiologia Plantarum, 87(2), 211–216. Khameneh, M. M. (2012). Echophysiological impact of water Shannon, M. C., & Grieve, C. M. (1998). Tolerance of vegetable crops stress on growth and development of mungbean. International to salinity. Scientia horticulturae, 78(1–4), 5–38. Journal of Agronomy and Plant Production, 3(12), 599–607. Timbilla, J. A., & Nyarko, K. O. (2004). A survey of cabbage Mafakheri, A., Siosemardeh, A. F., Bahramnejad, B., Struik, P. C., & production and constraints in Ghana. Ghana Journal of Agri- Sohrabi, Y. (2010). Effect of drought stress on yield, proline and cultural Science, 37(1), 93–101. chlorophyll contents in three chickpea cultivars. Australian Williamson, S., Ball, A., & Pretty, J. (2008). Trends in pesticide use Journal of Crop Science, 4(8), 580–585. and drivers for safer pest management in four African countries. Maggio, A., De Pascale, S., Ruggiero, C., & Barbieri, G. (2005). Crop Protection, 27(10), 1327–1334. Physiological response of field-grown cabbage to salinity and Xu, C., & Leskovar, D. I. (2014). Growth, physiology and yield drought stress. European Journal of Agronomy., 23, 57–67. responses of cabbage to deficit irrigation. Horticultural Science https://doi.org/10.1016/j.eja.2004.09.004. (Prague), 41, 138–146. Majumdar, S., Ghosh, S., Glick, B. R., & Dumbroff, E. B. (1991). Activities of chlorophyllase, phosphoenolpyruvate carboxylase Publisher’s Note Springer Nature remains neutral with regard to and ribulose-1, 5-bisphosphate carboxylase in the primary leaves jurisdictional claims in published maps and institutional affiliations. of soybean during senescence and drought. Physiologia Plan- tarum, 81(4), 473–480. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Plant Physiology Reports Springer Journals

Effect of drought length on the performance of cabbage (Brassica oleracea var capitata) in the forest-savannah transition zone, Ghana

Plant Physiology Reports , Volume 26 (1) – Nov 7, 2020

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Abstract

Plant Physiol. Rep. (January–March 2021) 26(1):74–83 https://doi.org/10.1007/s40502-020-00541-5 O R I G IN AL ARTI CL E Effect of drought length on the performance of cabbage (Brassica oleracea var capitata) in the forest-savannah transition zone, Ghana 1 2 E. Ackah R. Kotei Received: 6 February 2020 / Accepted: 22 September 2020 / Published online: 7 November 2020 The Author(s) 2020 Abstract The drought tolerance of Cabbage, Brassica transition zone, the initial and development stages could oleracea var capitata (Oxylus) was investigated by sub- tolerate drought stress up to 5 days whilst the mid stage jecting the initial, development and mid growth stages to could tolerate up to 7 days. varying drought lengths of 5, 7, 9, 11, 13 and 15 days in a 7 9 3 factorial experiment to determine the effect of each Keywords Oxylus  Drought  Brassica oleracea  Growth drought period at each growth stage on growth and yield. stages  Chlorophyll  Forest-savannah  Yield Data on number of opened leaves/plant, leaf area index (LAI), leaf chlorophyll content, head size and yield/ha were recorded due to drought effect at each growth stage. Introduction Analysis of variance at 5% probability level indicated that drought periods of 5–15 days at the initial stage signifi- Cabbage (Brassica oleracea L. var. capitata) is a veg- cantly reduced number of leaves, LAI and head size. Sig- etable crop grown worldwide including African countries nificant reduction in chlorophyll content and yield were (Grzywacz et al. 2010). It is widely adapted to the tropical due to drought beyond 11 and 5 days respectively at the climates (Blankson et al. 2013). In Ghana, cabbage pro- initial stage. Number of opened leaves increased signifi- duction is mostly popular among peri-urban and urban cantly with increasing drought length at the development dwellers in response to high demand (Timbilla and Nyarko stage; critical at 11 days drought. Significant reductions in 2004). Cabbage is also grown in cities and rural commu- LAI at the development and mid stages were critical at 11 nities in Ghana and it serves as an important source of and 9 days respectively whilst chlorophyll content was livelihood for many smallholder farmers in Ghana (Bai- significantly reduced at both the development and mid phethi and Jacobs 2009). stages by all drought periods. Significant reduction in head The world’s annual production of cabbage is around size at the development and mid stages was critical at 70,644,191 tons with an average yield of about 29.23 ton/ 7 days. Generally, the drought tolerance of cabbage ha (Kidane 2016). The major production constraints mostly increased from the initial to the mid-stage. To maintain reported in Ghana are insect pests, diseases, the need for economic yields of cabbage in the forest-savannah high fertilizer input and the high cost of pesticides (Wil- liamson et al. 2008). The changing patterns of climatic parameters like tem- perature and precipitation are emerging major threats for & E. Ackah bigemma1995@gmail.com vegetable production in the forest-savannah transition zone (Challinor et al. 2014). The effect of water stress is Department of Crop and Soil Science, College of Agriculture expected to increase with increasing length of drought. An Education, University of Education, Winneba, anticipated report revealed that up to 30% of the yields Mampong-Ashanti, Ghana from rain-fed farming in some south Asian countries could Department of Agriculture Engineering and Mechanization, be lost to increasing drought stress by 2050 (Intergovern- College of Agriculture Education, University of Education, mental Panel on Climate Change [IPCC], 2007). Though Winneba, Mampong-Ashanti, Ghana 123 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 75 cabbage production in the forest-savannah transition envi- an average annual rainfall of 1270 mm and two rainy ronment of Ghana is lucrative during the dry season seasons. The major rainy season starts in March and ends in (November to February), inadequate water availability August whilst the minor is between September and limits production (Ezeaku et al. 2014). November. The remaining months spans the harmattan Rise in temperature as well as increasing drought fre- (dry) season. The average annual temperature is 27 C with quency and length at any stage of crop growth can affect variations in mean monthly temperature ranging between the normal growth, flowering, pollination, fruit develop- 22 and 30 C (Kotei et al. 2015). ment and subsequently decrease crop yield (Hedhly et al. 2009). Changes in chlorophyll content are often measured Experimental design and drought application as a symptom of water stress (Majumdar et al. 1991). Cabbage has been classified as moderately susceptible to The experiment was a 7 9 3 factorial in a Randomized water stress, with the head formation period being more Complete Block Design (RCBD). The factors included sensitive (Shannon and Grieve 1998). Maggio et al. (2005) drought length with seven (7) treatments and three (3) reported that drought stress decreased the total head yield growth stages, each replicated thrice (3). The growth of cabbage from 50.5 to 17.5 tons/ha without stating the stages, including ‘‘initial/vegetative growth stage, devel- length or duration. In Brassica napus cultivars, water stress opment/head formation stage and mid/head filling stage’’ reduced chlorophyll a ? b content by 38% compared with were subjected to 5, 7, 9, 11, 13 and 15 days of complete the adequately watered plants (Paclik et al. 1996). drought. A control treatment (0 days drought) which The Forest-Savannah Transition Zone is known to received water continuously throughout the experimental experience drought spells even in the main rainy seasons period was set aside for the experiment. Seeds for the varying from 1 to 3 weeks. For this reason, farmers who research (Oxylus variety) were obtained from a certified depend mostly on rain are usually faced with the challenge Agro-Chemical shop and seedlings raised under conducive of selecting a suitable planting date for their seasonal nursery conditions for three (3) weeks and before trans- crops. Cabbage production in the Forest-Savannah Tran- planting. To avoid transplanting shock, all transplants were sition Zone thus experiences increasing frequency and watered for 4 days before drought application. The appli- length of drought which is bound to occur at any of the cation of drought however ended in March, 2018 while growth stages of the crop. Although several studies confirm experimental plants continued through the ‘‘late growth the significant effect that drought stress can depict on stage’’ in April, 2018. cabbage production, none of these studies indicated how Water supply to plants was completely based on how the long, within a particular growth stage, will the effect of drought periods were imposed and a well scheduled drip drought manifest. This study therefore sought to unveil the irrigation system. Water requirements were estimated using critical length of drought occurrence (in days) at the growth monthly Reference Evapotranspiration (ETo) obtained stages of cabbage from which growth and yield will be from Mampong Meteorological Agency (MMA) and Crop significantly affected. coefficient (Kc) of growth stages of the crop, according to FAO (2018) were used in computing various parameters for calibrating the drip system. Materials and methods The experimental field comprised of three main blocks representing the three growth stages with each measuring The study area 11 m 9 12.6 m with 1 m path from each. Each main block (growth stage) was further divided into six sub blocks, This study was conducted at the College of Agriculture representing 6 drought periods (5, 7, 9, 11, 13 and 15 days Education, University of Education, Winneba, the Mam- droughts) each measuring 2 m 9 12.6 m with a 1 m path pong campus during the dry season between December, from each other. Each sub block was further divided into 2017 and April, 2018. Mampong-Ashanti lies North of three plots, measuring 2 m 9 4.2 m with a 1 m path Kumasi within the Forest-Savannah Transition Zone between plots. The control treatment (0 days drought) between the Guinea Savanna in the North and Forest region comprised of a single block (2 m 9 12.6) divided into of the South of Ghana, and lies between longitudes three plots (2 m 9 4.2 m each). Each treatment plot hosted 0 00 0 00 0 00 0000 05 Wto1000 30 W and latitudes 6000 55 Nto 24 plants resulting in a total of 1368 experimental plants, 0 00 7000 30 N of the equator. The Mampong Municipality including the control. lies within the Wet Semi-Equatorial Forest Zone. Due to human activities like charcoal production, lumbering and bush fires, the forest vegetation, particularly the North- Eastern part, has been reduced to Savannah. The area has 123 76 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 Calibration of the drip system Table 2 Kcs for the growth stages of Brassica Oleracea. Source: FAO (2018) Twenty (20) containers were used to collect water ran- Crop stage Initial Development Mid Late domly from emitters scattered between the first and last Kc 0.4 0.7 0.95 0.9 dripping points in 15 min and the average volume of water was determined to be 150 mL = 0.15 L. Dripping rate of the system was estimated using Eq. 1. 0:15 L min Drip per minute ¼ ¼ 0:01 L ð1Þ coefficient (UC) and emission uniformity (EU) using dis- 15 min charge measurement data from 20 emitters. The uniformity coefficient equation according to Dudek and Fernandez Crop evapotranspiration (ETc)/water requirement (2015) and the emission uniformity equation were employed to compute the uniformity parameters of the drip The crop evapotranspiration (ETc) for the growth stages system. These equations are simple and are widely used in representing the water requirement of each particular stage the present days (Al-Ghobari, 2012; Asif et al. 2015): were estimated using Eq. 2. SD Uniformity coefficientðÞ UC ¼ 100 1  ð5Þ day ETc mm ¼ Mean monthly ETo  Kc ð2Þ rffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi Mean monthly ETos for the four (4) months period of SD ¼ jj q  q ð6Þ the study and Kcs for the growth stages of cabbage are presented in Tables 1 and 2 respectively. alq Emission uniformityðÞ EU ¼  100 ð7Þ Irrigation time Coefficient of variation (CV ) In order to match the estimated ETc with the dripping rate -min (L ), ETc for each growth stage was converted from According to Asif et al. (2015), the coefficient of variation -day -day L to mm . is generally used as a measure of emitter flow variation due -day -day By conversion, 4.1 mm = 0.3 L (Arku et al. to variation in manufacturing characteristics of the emis- 2012). sion devices. The CV describes the quality of the material Hence, and processes used to manufacture the emission devices. It is determined from flow measurements for several identical ETcðÞ mm/day 0:3 L/day day Converted ETc L ¼ ð3Þ emission devices and is computed using Eq. 8. 4:1 mm/day SD Time to run the system in minutes per day was estimated CV ¼ ð8Þ using Eq. 4. where q = discharge of emitter i, q = overall average of Converted ETcðÞ L/day Irrigation time ¼ ð4Þ emitter discharges, n = number of emitters, q = average alq Dripping rateðÞ L/min low/min-quarter emitter discharge, SD = standard devia- Estimated time for running the irrigation system during tion, CV = manufacturers’ coefficient of variation for the growth periods are presented in Table 3. emitters. Evaluation of the drip system Emission uniformity rating The drip irrigation system used in the study was evaluated Dudek and Fernandez (2015) rated emission uniformity of its delivery efficiency by estimating its uniformity values as follows: \77% ¼ Very poor 77  82 ¼ Poor 83  90% ¼ Acceptable [ 90% ¼ Excellent Table 1 Monthly ETo for study area. Source: Meteorological Service Department, Mampong agency The emission coefficient (EU), 97.07% estimated from Month Jan Feb Mar Apr the catch results collected in this study indicates that the -day drip system used for water application was highly efficient ETo (mm ) 4.94 5.39 4.63 3.86 with only 2.93% water loss. The uniformity coefficient (UC) and CV values were 95.68% and 0.043 respectively. 123 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 77 Table 3 Estimated times for running the irrigation system Stage (days) Month/period ETo Kc ETc Converted ETc Dripping rate (L/ Time (days) (mm/day) (mm/day) (L/day) min) (min/day) Initial (20 days) Jan—20 4.94 0.40 1.98 0.14 0.01 14 Development Jan—4 4.94 0.70 3.46 0.25 0.01 25 (30 days) Feb—26 5.37 0.70 3.76 0.28 0.01 28 Mid (20 days) Feb—2 5.37 0.95 5.10 0.37 0.01 37 Mar—18 4.63 0.95 4.40 0.32 0.01 32 Late (20 days) Mar—12 4.63 0.90 4.17 0.30 0.01 30 Apr—8 3.86 0.90 3.47 0.25 0.01 25 According to Asif et al. (2015), the ranges of Cv values and Yield and yield components their appropriate interpretations are as follows: Cabbage heads were harvested at the end of the ‘‘late [ 0:4 ¼ Unacceptable 0:40:3 ¼ Low growth stage’’ when heads were fully filled and thus, felt 0:30:2 ¼ Acceptable 0:2  0:1 ¼ Very good hard when squeezed. Head size/girth and weight were \0:1 ¼ Excellent measured with fiber glass tape and electronic scale Thus, the UC and CV values estimated from the catch respectively. Head weights were used to estimate yield data show high efficiency of the drip system. (tons/ha). Growth and physiological measurements Statistical analysis Number of opened leaves, leaf area index (LAI) and Data on growth parameters including number of opened chlorophyll content index were measured on 9 plants from leaves, LAI and leaf chlorophyll content index were sub- each replicate at the end of each growth stage. Normal jected to a one-way analysis of variance analysis irrigation resumed after each drought treatment. For the (ANOVA) with drought length as the varying factor for initial stage, the leaves of selected plants were counted and each growth stage whilst data on head size and yield were the average estimated to represent the number of leaves of subjected to two-way analysis of variance with drought a single plant before head formation. For the development length and growth stage as varying factors using Genstat and mid stages, the outer leaves were counted and the statistical package windows version 11.1 (2008). This average estimated at the end of the stages. analytical strategy was employed owing to physiological The leaf area of selected crops was measured indirectly differences of the crop at the different growth stages which using Imagej software version 1.46r (Scurlock et al. 2001). could result in biased growth at the stages. As a result, The selected leaves were captured at equal height above comparing growth at the stages may be unfair; however, ground level. The images were then cropped in adobe the resultant effect of drought at the different growth stages Photoshop CS6 to obtain the actual area of the canopy, on yield parameters are fairly comparable. Where signifi- excluding parts of the ground which appeared in the orig- cant differences existed, mean separation was done using inal image. The resultant image was transported into the the LSD criterion at 5% (0.05) probability level. imagej where the area of the canopy was estimated. The area of land occupied by the selected plants was also estimated. Leaf area index was then calculated as Results canopy area (Scurlock et al. 2001). ground area Number of opened leaves/plant Leaf chlorophyll content index was measured using the Chlorophyll meter (CCM-200 Plus). The leaf chlorophyll With increasing drought length, number of opened leaves content index estimates were taken 3 times from six fully decreased at the initial stage, increased at the development expanded leaves, two (2) leaves each from the bottom set, stage but remained constant during the mid-stage. Analysis middle set and upper set of leaves of selected plants. The of variance of results (Table 4), indicated significant (P average chlorophyll content was estimated in CCI. B 0.05) reduction in number of leaves at the initial stage 123 78 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 Table 4 Mean number of Growth stage Drought length (days) LSD CV(%) opened leaves as influenced by drought length at different 0 5 7 9 11 13 15 growth stages of B. oleracea var a b b b b b b capitata Initial 13 11 10 10 10 10 10 1.4 7.6 a a a a b ab ab Development 19 19 19 19 22 21 21 2.0 5.7 Mid 20 20 20 20 20 20 20 1.2 ns 3.3 Between column means bearing different superscripts differ significantly (P B 0.05) due to all drought periods (5–15 days) compared to the LAI under 9, 11, 13 and 15 days of droughts respectively control. The control plants produced the highest number of as compared to the control. leaves (13), preceded by 5 days drought stressed plants (11 Leaf chlorophyll content index (CCI) leaves) whilst the rest of the drought periods, although similar in their effects on number of leaves at the initial stage, each resulted in 23.1% reduction in number of Leaf chlorophyll content index generally decreased as leaves. At the end of the development stage, number of drought length advanced regardless of growth stage opened leaves significantly (P B 0.05) increased from 19 (Table 6). Leaf chlorophyll content was significantly (P to 22 leaves under 11 days drought and to 21 leaves under B 0.05) decreased under 13 and 15 days drought occurring 13 and 15 days droughts but 5–9 days drought periods had at the initial stage (12.96% and 15.91% respectively) no significant (P [ 0.05) effect on number of opened compared to the control. At the development stage, leaf leaves at the development stage. At the mid-stage, drought chlorophyll content index was significantly (P B 0.05) length had no significant (P [ 0.05) effect on number of reduced under each of the applied drought periods com- opened leaves (Table 4). pared to the control. Significant reductions of 11.8%, 15.1%, 17%, 17.9%, 49.7% and 48.9% were due to 5, 7, 9, Leaf area index (LAI) 11, 13 and 15 days drought respectively. Similar to the development stage, chlorophyll content index of cabbage Results indicate that as drought length increased LAI leaf at the mid-stage was significantly (P B 0.05) reduced decreased at all growth stages (Table 5). Analysis of by all applied drought periods compared to the control. variance indicated that LAI at the initial stage was signif- Significant reductions of 10.8%, 12.9%, 12.7% and 48.9% icantly (P B 0.05) highest for the control (0.013) and were due to 5, 7, 9 and 15 days droughts respectively lowest (0.005) for 15 days drought stressed plants. Plants whilst 11 and 13 days droughts reduced leaf chlorophyll subjected to 5, 11, 13 and 15 days droughts at the initial content by 17.2% at the mid-stage. stage were significantly reduced of their LAI by 30.8%, 53.8%, 46.2% and 61.5% respectively whilst 7 and 9 days Head size/girdle at harvest (cm) droughts significantly reduced LAI at the initial stage by 30.5% compared to the control. LAI at the development Head size, when compared across the growth stages gen- stage was significantly (P B 0.05) reduced only under erally increased from the initial stage to the mid-stage 15 days drought. The control plants recorded the highest (initial \ development \ mid), indicating a decreasing LAI of 0.043 followed by 5 days drought (0.039) with effect of the same drought period on head size as the crop 15 days drought stressed plants recording the significantly advances from one stage to another, with head size at the (P B 0.05) lowest (0.033) which was 23.3% lower than initial stage being significantly (P B 0.05) lowest that of the control plants. At the mid-stage, significant (57.56 cm) compared to the development and mid stages reductions of 18.6%, 25.6%, 30.2% and 37.2% occurred in (61.47 cm and 61.96 cm respectively) (Table 7). Table 5 Mean LAI as Growth stage Drought length (days) LSD CV (%) influenced by drought length at different growth stages of B. 0 57911 13 15 oleracea var capitata a b bc bc c b c Initial 0.013 0.009 0.008 0.008 0.006 0.007 0.005 0.002 15.5 a a a a b ab ab Development 0.043 0.039 0.039 0.039 0.035 0.034 0.033 0.009 13.8 a ab ab bc cd cd d Mid 0.043 0.039 0.038 0.035 0.032 0.030 0.027 0.005 8.7 Between column means bearing different superscripts differ significantly (P B 0.05) 123 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 79 Table 6 Mean leaf chlorophyll Growth stage Drought length (days) LSD CV (%) content index (CCI) as influenced by drought length at 0 5 7 9 11 13 15 different growth stages of B. a a a a ab b b oleracea var capitata Initial 80.35 78.16 79.27 78.98 72.27 69.90 67.57 5.986 4.5 a b b b b c c Development 80.35 70.86 68.21 66.66 66.00 40.45 41.07 2.407 4.8 a b b bc bc c c Mid 80.35 72.83 71.64 70.00 70.18 66.49 66.51 4.712 3.7 Between column means bearing different superscripts differ significantly (P B 0.05) Generally, head size due to drought length within a Nine (9) and 15 days drought differed significantly (P particular growth stage significantly (P B 0.05) decreased B 0.05) in terms of yield but both statistically similar with increasing drought length from 66.46 cm without (P [ 0.05) to 11 and 13 days droughts. Interactively (drought length * growth stage), five (5) drought to 54.88 cm under 15 days drought. Significant reductions of 3.64%, 9.04%, 10.53%, 10.79%, 13.17% and days drought at any of the growth stages and 7 days 17.42% were due to 5, 7, 9, 11, 13 and 15 days of drought drought at the development and mid stages had no signif- compared to the control. icant (P [ 0.05) effect on final yield compared to the Interacting growth stage with drought length indicated control. Drought beyond 5 days at the initial stage and that all applied drought periods at the initial stage signifi- drought beyond 7 days at the development and mid stages cantly (P B 0.05) decreased final head size as compared to significantly (P B 0.05) decreased yield compared to the the control. All but 5 days drought occurring at the control. The control plants produced a maximum yield of development and mid stages significantly (P B 0.05) 52.59 tons/ha which was 53.4% higher than the minimum decreased final head size as compared to the control. yield of 24.5 tons/ha produced by plants subjected to Overall, the minimum head size (52.88 cm) was recorded 15 days drought during the initial stage. Subjecting the under 15 days drought occurring at the initial stage which initial stage to 7, 9, 11 and 13 days drought resulted in was 20.4% lower than that of the control. Seven (7) days significant yield reductions of 22%, 44.2%, 45.2% and drought occurring at the initial, development and mid 48.3% respectively compared to the control. Nine (9), 11, stages significantly decreased final head size by 11.7%, 13 and 15 days droughts at the development stage caused 7.9% and 7.5% respectively. Nine (9) days drought at the 34.0%, 36.9%, 43.9% and 47.8% significant yield reduc- initial, development and mid stages decreased head size by tions respectively whereas 9, 11, 13 and 15 days droughts 17.1%, 7.6% and 6.8% whilst 11 days drought had 18.2%, at the mid stage decreased yield by 21.0%, 25.0%, 22.7% 7.3% and 6.9% significant reductions respectively com- and 24.6% respectively compared to the control. pared to the control. 13 days drought resulted in 19.5%, 10.3% and 9.7% whilst 15 days drought at the respective Measured parameters and their critical length growth stages decreased final head size by 20.4%, 16.7% of drought (days) and 15.1% compared to the control. Critical drought length from which the measured parame- Yield (tons/ha) ters started experiencing significant reduction are presented in Table 8. Drought duration of 5 days and beyond at the Similar to head size, yield of cabbage generally increased initial stage were critical for number of opened leaves, LAI across the growth stages from initial to mid for each and head size whereas 13 and 7 days length of drought at drought period (initial \ development \ mid) (Table 7). the initial stage were critical against chlorophyll content Yield of cabbage differed significantly amongst the three index and yield respectively. At the development stage, growth stages with the yield due to drought at the initial 11 days drought was critical against number of opened stage (36.25 tons/ha) being the significantly (P B 0.05) leaves and LAI, 5 days was critical against chlorophyll lowest compared to those at the development (39.10 tons/ content index whilst 7 days was critical against both yield ha) and mid stages (44.56 tons/ha). components. At the mid stage, number of opened leaves Yield also decreased with increasing drought within a was not affected by drought length. However, 9 days particular stage. Five (5) days drought had no significant drought at the mid stage was critical against LAI and yield (P [ 0.05) effect on yield whilst the rest of the applied whereas 5 and 7 days drought were critical for chlorophyll drought periods significantly (P B 0.05) reduced yield content index and head size respectively. compared to the control. Five (5) and 7 days drought periods differed significantly (P B 0.05) from the rest. 123 80 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 Table 7 Effect of Drought Length at different growth stages of B. Discussion oleracea var capitata on final head size/girth (cm) and yield (tons/ha) Number of opened leaves/plant Treatment Head size/girth (cm) Yield (tons/ha) Growth stage Lesser leave numbers at the initial stage might be due to a a Initial (I) 57.56 36.25 decreased leaf formation and growth. Increased number of b b Development (D) 61.47 39.10 opened leaves at the development stage is attributable to b c Mid (M) 61.96 44.56 delayed cupping due to drought stress. At the mid-stage LSD (0.05) 1.553 2.398 however, heads had already formed and drought stress Drought length (days) would have no effect on the number of outer leaves. a a 0 66.46 52.59 Decreasing number of leaves at the initial stage was critical b a 5 64.04 50.99 even under 5 days drought whereas an increase in the c b 7 60.45 44.19 number of opened leaves due to delayed cupping at the c c 9 59.46 35.20 development stage was critical under 11 days drought c cd 11 59.29 33.83 (Table 8). Lalinia et al. (2012) reported that drought stress c cd 13 57.71 32.44 at the flowering stage decreased number of branches in d d 15 54.88 30.54 mungbean. Gupta et al. (1995) also reported reduced LSD (0.05) 2.372 3.664 number of branches in chickpea when drought was Interactions imposed at the early flowering stage. In the present study, a a 0*I 66.46 52.59 the initial stage of B. oleracea var capitata appeared to be a a 0*D 66.46 52.59 most sensitive to increasing drought length than the a a 0*M 66.46 52.59 development and mid stages in terms of leave number. bc ab 5*I 61.94 50.26 According to Kabiri et al. (2014), drought stress at the abd ab vegetative stage is of less importance than at the repro- 5*D 64.67 50.98 ab a ductive stage of tension with regards to impact on yield and 5*M 65.50 51.72 ce bd yield components. However, drought stress at the vegeta- 7*I 58.67 41.04 cd bd tive stage impacts leaf and stem development, photosyn- 7*D 61.20 45.24 bc ab thesis, and the accumulation of important plants 7*M 61.49 46.30 ef cf components (Fathi and Tari 2016). The biophysical factors 9*I 55.10 29.37 cd ce mostly affected are the size and number of leaves in plants 9*D 61.38 34.69 bc bd (Ghodsi et al. 1998). 9*M 61.91 41.56 f cf 11*I 54.36 28.83 bc cef Leaf area index (LAI) 11*D 61.64 33.20 bc de 11*M 61.88 39.46 f f Restriction on leaf area is the first line of defense against 13*I 53.50 27.19 water stress. Similar to number of leaves, the initial stage ce cf 13*D 59.59 29.50 was most sensitive to increasing drought in terms of LAI as c bd 13*M 60.03 40.63 reduction in LAI at this stage was observed under 5 days f f 15*I 52.88 24.50 drought and beyond. Whereas at the development and mid ef f 15*D 55.33 27.46 stages critical drought periods were 11 and 9 days ef de 15*M 56.43 39.67 respectively (Table 8). Reduced LAI at the various growth LSD (0.05) 4.109 6.346 stages were due to already mentioned factors that resulted CV % 4.1 9.6 in the decrease in the number and size of opened leaves. Between column means bearing different superscripts differ signifi- LAI results from this study are in agreement with that of cantly (P B 0.05) Rao and Bhatt (1988) who reported reduction in leaf area of Capsicum annum L. to drought stress at all the growth stages, viz., vegetative, flowering and fruiting. Leaf Chlorophyll content index (CCI) Decrease in leaf chlorophyll content index due to drought stress is considered a typical symptom of pigment photo 123 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 81 Table 8 Measured parameters and their critical length of drought (days) at different growth stages Growth stage Parameter Number of opened leaves LAI Chlorophyll content index (CCI) Head size (Cm) Yield (tons/ha) Initial 5 5 13 5 7 Development 11 11 5 7 7 Mid ns 9 5 7 9 ns non-significant oxidation and chlorophyll degradation (Anjum et al. 2011). which led to increased number of opened leaves (Table 4, A decrease in total chlorophyll content index with development stage), especially under 11–15 days drought. increasing drought stress implies a lowered capacity for During this stage, leaves are expected to form heads but light harvesting. Since the production of reactive oxygen became flaccid under lengthy water stress and as a result species mainly depends on excess energy absorption in the remained opened around the head. Also, leaf senescence photosynthetic apparatus, this might be avoided by after rapid vegetative growth led to reduced amount of leaf degrading the absorbing pigments (Mafakheri et al. 2010). chlorophyll which consequently reduced tissue formation In relation to chloroplastic protein hydrolysis and thereby reducing leave sizes at the mid stage. According to decreasing leaf pigments (Sgherri et al. 1993), it could be Xu and Leskovar (2014), even 50% and 75% deficit irri- expressed that drought effect on chlorophyll in leaf due to gation applied before and after head formation of cabbage drought is a primary stage in degradation of proteins. Also, significantly decreased final head size. They also reported the decrease in chlorophyll under drought stress might be significant reduction in head size under 50% deficit irri- as a result of reduced synthesis of the main chlorophyll gation applied to the head formation stage. Interacting pigment complexes encoded by the cab gene family (Al- growth stage with drought length indicated reduced head lakhverdiev et al. 2000). Decreased chlorophyll content size even under 5 days drought at the initial stage whereas may also be attributed to reduced dry matter production as at the development and mid stages this was critical at a result of reduced leaf photosynthesis. This effect is in 5 days drought. agreement with the findings of Premachandra et al. (1991) who reported 67–97% lower leaf photosynthesis in stressed Yield (tons/ha) maize plants than in watered plants. Critical drought peri- ods for chlorophyll reduction were observed under 13 days Generally, yield reduction was greater when the initial drought at the initial stage whereas even 5 days drought at stage was subjected to drought irrespective of the length. the development and mid stages led to chlorophyll reduc- Also yield reduction was observed even under 7 days tion, indicating that the development and mid stages were drought at the initial and development stages whereas at the most sensitive to increasing drought in terms of chlorophyll mid stage yield reduction was critical under 9 days content. drought. Water stress during the initial stage reduces yield by reducing leave number and sizes or area while drought Head size/girdle at harvest (cm) stress at the development stage reduces yield by decreasing the number of leaves that entered into the head. Drought Final head size was influenced by the number of leaves, stress at the mid stage however reduces yield by reducing leaf area and the amount of energy intercepted throughout the plant of its moisture content which subsequently the growth period. Lower values of head size due to decreased head weight. Decrease in chlorophyll content at drought effect at the initial stage may be as a result of any stage also affects the formation of new tissues which decreased leaf formation potential indicated as reduced consequently decrease the final head weight. According to leave numbers and sizes. Although decrease in amount of MoFA average yields of 30–40 tons/ha are normal. FAO chlorophyll at the initial stage under short and moderate (2018) also stated that a maximum of about 50 tons/ha can droughts were not significant, consequences on growth be obtained when sprayed and well-fertilized. Under ideal significantly affected leaf numbers and sizes which sub- climatic conditions and good irrigation and crop manage- sequently reduced head size at maturity. Decreased head ment, yields can be as high as 85 tons/ha (FAO 2018). sizes due to drought period beyond 5 days at the devel- Moradi et al. (2008) reported that drought stress at the opment stage may be as a result of the delayed cupping 123 82 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 vegetative and reproductive stages reduced mungbean seed References yield by 9 and 49% respectively. Al-Ghobari, H. M. (2012). A comparison of water application uniformity for drip irrigation system above and below soil surface at various soil depths and scheduling techniques in arid Conclusions region. WIT Transactions on Ecology and the Environment, 168, 311–322. Allakhverdiev, S. I., Sakamoto, A., Nishiyama, Y., & Murata, N. Significant changes in number of opened leaves at the (2000). Inactivation of photosystems I and II in response to initial and development stages were critical under 5 and osmotic stress in Synechococcus. Contribution of water channels. 11 days drought respectively. Reduction in LAI at the Plant Physiology, 122(4), 1201–1208. initial, development and mid stages were critical under 5, Anjum, S. A., Xie, X. Y., Wang, L. C., Saleem, M. F., Man, C., & Lei, W. (2011). Morphological, physiological and biochemical 11 and 9 days respectively. Chlorophyll content index was responses of plants to drought stress. African Journal of reduced under critical drought periods of 13 days at the Agricultural Research, 6(9), 2026–2032. initial stage and 5 days at both the development and mid Arku, A. Y., Musa, S. M., & Mofoke, A. L. E. (2012). Determination stages. Number of opened leaves was however not affected of water requirement and irrigation timing for Amaranthus hybridus in Maiduguri metropolis, north-eastern Nigeria. In by drought occurrence at the mid stage. Fourth international conference on sustainable irrigation (pp. Projected reduction effect of drought on head size at 279–289). harvest was critical under 5 days drought at the initial stage Asif, M., Ahmad, M., Mangrio, A. G., Akbar, G., & Memon, A. H. and 7 days drought at the development and mid stages. (2015). Design, evaluation and irrigation scheduling of drip irrigation system on citrus orchard. Pakistan Journal of Mete- Since yield reduction was critical under 7 days drought at orology, 12(23), 37–48. the initial and development stages as well as under 9 days Baiphethi, M. N., & Jacobs, P. T. (2009). The contribution of drought at the mid stage, it suggest that implementing subsistence farming to food security in South Africa. Agrekon, water application at regular intervals of 7 days at the initial 48(4), 459–482. Blankson, A. W., Gurr, G. M., Gitau, C. W., Nicol, H. I., Munyakazi, and development stages as well as 9 days at the mid stage L., & Stevenson, P. C. (2013). Tri-trophic insecticidal effects of could maintain economic yield although growth may be African plants against cabbage pests. PLoS ONE, 8(10), e78651. moderately suppressed. https://doi.org/10.1371/journal.pone.0078651. Challinor, A. J., Watson, J., Lobell, D. B., Howden, S. M., Smith, D. Acknowledgement The Authors thank the Meteorological Service R., & Chhetri, N. (2014). A meta-analysis of crop yield under Department, Mampong-Ashanti Agency for providing climate data climate change and adaptation. Nature Climate Change, 4(4), (ETos) for scheduling our irrigation system. Dudek, T. A., & Fernandez, R. T. (2015). Conducting a water application uniformity evaluation for an overhead sprinkler Author contributions RK conceived the original idea. Both Authors irrigation system in the nursery (p. 15). Consultado: Michigan contributed to the experimental designed. EA carried out the exper- State University Extension. iment, performed analytical computations and wrote the first draft of Ezeaku, I. E., Okechukwu, E. C., & Aba, C. (2014). Climate change the manuscript. RK supervised the project and commented on pre- effects on maize (Zea mays) production in Nigeria and strategies vious versions of the manuscript. Both Authors read and approved the for mitigation. Asian Journal of Science and Technology, 5, final manuscript for submission. 862–871. Food and Agriculture Organization (FAO). (2018). Crop description Compliance with ethical standards and climate|Cabbage. Available at: https://www.fao.org/land- water/databases-andsoftware/cropinformation/cabbage/en/. Conflict of interest The Authors declare that they have no conflict of Fathi, A., & Tari, D. (2016). Effect of drought stress and its interest. mechanism in plants. International Journal of Life Sciences, 10(1), 1–6. https://doi.org/10.3126/ijls.v10i1.14509. Ethical approval The studies involved in this article did not inclu- Ghodsi, M., Nazeri, M., & Zarea-Fizabady, A. (1998). The reaction of ded animals or human participants as objects of research. new cultivars and elite lines of spring wheat into drought stress. In Collection of abstract articles of 5th Iranian agronomy and Open Access This article is licensed under a Creative Commons plant breeding conference, Karaj, Iran (p. 252). Attribution 4.0 International License, which permits use, sharing, Grzywacz, D., Rossbach, A., Rauf, A., Russell, D. A., Srinivasan, R., adaptation, distribution and reproduction in any medium or format, as & Shelton, A. M. (2010). Current control methods for diamond- long as you give appropriate credit to the original author(s) and the back moth and other brassica insect pests and the prospects for source, provide a link to the Creative Commons licence, and indicate improved management with lepidopteran-resistant Bt veg- if changes were made. The images or other third party material in this etable brassicas in Asia and Africa. Crop Protection, 29(1), article are included in the article’s Creative Commons licence, unless 68–79. indicated otherwise in a credit line to the material. If material is not Gupta, S. N., Dahiya, B. S., Malik, B. P. S., & Bishnoi, N. R. (1995). included in the article’s Creative Commons licence and your intended Response of chickpea to water deficits and drought stress. use is not permitted by statutory regulation or exceeds the permitted Haryana Agriculture University Journal of Research, 25(1/2), use, you will need to obtain permission directly from the copyright 11–19. holder. To view a copy of this licence, visit http://creativecommons. org/licenses/by/4.0/. 123 Plant Physiol. Rep. (January–March 2021) 26(1):74–83 83 Hedhly, A., Hormaza, J. I., & Herrero, M. (2009). Global warming Moradi, A., Ahmadi, A., & Hossein Zadeh, A. (2008). Agro- and sexual plant reproduction. Trends in Plant Science, 14(1), physiological responses of mung bean (cv. Partov) to severe and 30–36. moderate drought stress applied at vegetative and reproductive IPCC, 2007 Climate Change. (2007). Impacts, adaptation and growth stages. JWSS-Isfahan University of Technology, 12(45), vulnerability. In M. L. Parry, O. F. Canziani, J. P. Palutikof, P. 659–671. J. van der Linden, & C. E. Hanson (Eds.), Contribution of Paclik, R. L., & Sakova, C. V. (1996). Reaction of different cultivars working group II to the fourth assessment report of the of Brassica napussubsp. oleifera to water stress. Fytotechnicka- intergovernmental panel on climate change (p. 976). Cambridge, Rada, 1, 55–62. UK: Cambridge University Press. Premachandra, G. S., Saneoka, H., Kanaya, M., & Ogata, S. (1991). Kabiri, R., Nasibi, F., & Farahbakhsh, H. (2014). Effect of exogenous Cell membrane stability and leaf surface wax content as affected salicylic acid on some physiological parameters and alleviation by increasing water deficits in maize. Journal of experimental of drought stress in Nigella sativa plant under hydroponic botany, 42(2), 167–171. culture. Plant Protection Science, 50(1), 43–51. Rao, S., & Bhatt, R. M. (1988). Photosynthesis, transpiration, Kidane, D. (2016). Assessment of cabbage production practices and stomatal diffuse resistance, and relative water content of effect of NP fertilizer rate on head yield and yield components in capsicum (Bell Pepper) grown under water stress. Photosynthet- Lay Armacheho district. Doctoral dissertation, Bahir Dar ica (Praha), 22(3), 377–382. University. Scurlock, J. M. O., Asner, G. P., & Gower, S. T. (2001). Worldwide Kotei, R., Agyare, W. A., Kyei-Baffour, N., Frempong, N. K., & Atta- historical estimates of leaf area index, 1932–2000. ORNL/TM- Darkwa, T. (2015). Development of groundwater recharge model 2001/268, p. 34. for the sumanpa catchment at Ashanti-Mampong-Ashanti Area Sgherri, C. L. M., Pinzino, C., & Navari-Izzo, F. (1993). Chemical in Ghana. changes and O —production in thylakoid membranes under Lalinia, A. A., Hoseini, N. M., Galostian, M., Bahabadi, S. E., & water stress. Physiologia Plantarum, 87(2), 211–216. Khameneh, M. M. (2012). Echophysiological impact of water Shannon, M. C., & Grieve, C. M. (1998). Tolerance of vegetable crops stress on growth and development of mungbean. International to salinity. Scientia horticulturae, 78(1–4), 5–38. Journal of Agronomy and Plant Production, 3(12), 599–607. Timbilla, J. A., & Nyarko, K. O. (2004). A survey of cabbage Mafakheri, A., Siosemardeh, A. F., Bahramnejad, B., Struik, P. C., & production and constraints in Ghana. Ghana Journal of Agri- Sohrabi, Y. (2010). Effect of drought stress on yield, proline and cultural Science, 37(1), 93–101. chlorophyll contents in three chickpea cultivars. Australian Williamson, S., Ball, A., & Pretty, J. (2008). Trends in pesticide use Journal of Crop Science, 4(8), 580–585. and drivers for safer pest management in four African countries. Maggio, A., De Pascale, S., Ruggiero, C., & Barbieri, G. (2005). Crop Protection, 27(10), 1327–1334. Physiological response of field-grown cabbage to salinity and Xu, C., & Leskovar, D. I. (2014). Growth, physiology and yield drought stress. European Journal of Agronomy., 23, 57–67. responses of cabbage to deficit irrigation. Horticultural Science https://doi.org/10.1016/j.eja.2004.09.004. (Prague), 41, 138–146. Majumdar, S., Ghosh, S., Glick, B. R., & Dumbroff, E. B. (1991). Activities of chlorophyllase, phosphoenolpyruvate carboxylase Publisher’s Note Springer Nature remains neutral with regard to and ribulose-1, 5-bisphosphate carboxylase in the primary leaves jurisdictional claims in published maps and institutional affiliations. of soybean during senescence and drought. Physiologia Plan- tarum, 81(4), 473–480.

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