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EVALUATION OF PYRIFLUQUINAZON FOR CONTROL OF SWEETPOTATO WHITEFLY IN FALL CANTALOUPES, 2012

EVALUATION OF PYRIFLUQUINAZON FOR CONTROL OF SWEETPOTATO WHITEFLY IN FALL CANTALOUPES, 2012 Arthropod Management Tests 2013, Vol. 38 doi: 10.4182/amt.2013.E18 (E18) CANTALOUPE: Cucumis melo L. var. cantalupensis Naudin, ‘Gold Express' EVALUATION OF PYRIFLUQUINAZON FOR CONTROL OF SWEETPOTATO WHITEFLY IN FALL CANTALOUPES, 2012 John C. Palumbo University of Arizona, Yuma Agricultural Center th 6425 W. 8 St., Yuma, Arizona 85364 Phone: (928) 782-3836 E-mail: jpalumbo@ag.arizona.edu Sweetpotato whitefly (SWF): Bemisia tabaci (Gennadius) – biotype B With the loss of endosulfan on melons, this trial was designed to evaluate the efficacy of an experimental foliar insecticide against adult whiteflies in spring melons. Cantaloupe plots planted with ‘Gold Express’ were established at the Yuma Agricultural Center on 16 Aug, 2012 and managed similarly to local growing practices. Plots consisted of a single 84-inch bed, 45 ft long with a 7 ft buffer between each plot. The study was designed as a RCB design with 4 replicates / treatment. The treatment combinations and rates are shown in the tables below. Three foliar spray treatments were applied on 28 Aug, 5 and 13 Sep with a tractor driven CO powered sprayer that delivered 30 gpa at 50 psi, using 4 – TX18 ConeJet nozzles per bed as a broadcast spray. All spray treatments included an adjuvant, DyneAmic at 0.25% vol/vol. Populations of whitefly adults were evaluated at 1, 4 and 7 day intervals following each application (DAT). Adult populations were estimated using a modified vacuum method that employed a 2- gal portable vacuum (DeWALT, Baltimore, MD) which was fitted with cloth-screened 40 Dram containers to capture and retain vacuumed adults. On each sample date, 5 separate plants from each replicate were sampled by vacuuming the terminal area of the plants for 3 s. Containers with adults were taken into the laboratory, placed in a freezer for 24 h after which the number of adults/ plant was recorded. Immature densities were estimated at 7 and 14 days following each application, where 2 leaves were collected from each plant from basal nodes on the primary vine. Leaves were taken into the laboratory where densities of eggs and nymphs were counted on two, 2-cm leaf discs of each leaf using a dissecting microscope. Adult data were averaged at each sample interval, and immature data where averaged across all sample dates. Because of heterogeneity of mean variances, data were log transform (mean+1) and subjected to ANOVA; means were separated using a F-protected LSD (P ≤ 0.05). Actual non- transformed means are presented in the tables. Adult pressure was heavy during this trial. The primary goal of this trial was to evaluate Pyrifluquinazon, a compound with translaminar activity known for its whitefly activity, alone and in combination with Courier for control of both adults and nymphs. Scorpion was included as a commercial standard. Pyrifluquinazon, regardless of rate applied, provided excellent knockdown activity at 1 and 4 DAT compared to the untreated check following each spray application (Table 1). However, nd rd it was only after the 2 and 3 applications that significant residual control of SWF adults at 7 DAT was observed. The addition of Courier did not significantly enhance the adult activity of pyrifluquinazon, however this combination provided significantly better control of nymphs than the Courier used alone (Table 2). As anticipated, Courier did not provide consistent control of adults. For the second consecutive season, Pyrifluquinazon has shown adult whitefly control comparable to the standard. No phytotoxicity was observed. This research was supported by a grant from the California Melon Research Board, PAL-13. Table 1. Adult SWF / sample Rate amt 1-DAT1 4-DAT1 7-DAT1 Treatment/formulation product/acre 29-Aug 31-Aug 4-Sep Pyrifluquinazon 20SC 3.2 oz 20.3c 13.9cd 224.8a Pyrifluquinazon 20SC 1.6 oz 11.8c 9.8d 197.6a Pyrifluquinazon 20SC 0.8 oz 18.0c 24.7cd 195.0a Courier 40SC 12 oz 111.9b 127.6b 243.7a Pyrifluquinazon+Courier 0.8 oz+12 oz 13.8c 13.3cd 210.4a Pyrifluquinazon+Courier 1.6 oz+12 oz 15.1c 21.3cd 202.8a Scorpion 35SL 7 oz 16.4c 15.7cd 220.0a Untreated check --- 230.2a 276.3a 392.1a 1 Arthropod Management Tests 2013, Vol. 38 doi: 10.4182/amt.2013.E18 Table 1. continued Adult SWF / sample Rate amt 1-DAT2 4-DAT2 7-DAT2 Treatment/formulation product/acre 6-Sep 9-Sep 12-Sep Pyrifluquinazon 20SC 3.2 oz 42.9c 5.1c 36.9cde Pyrifluquinazon 20SC 1.6 oz 33.5c 8.1bc 42.5cd Pyrifluquinazon 20SC 0.8 oz 45.6c 9.4c 51.0c Courier 40SC 12 oz 201.8b 90.7a 258.1b Pyrifluquinazon+Courier 0.8 oz+12 oz 43.5c 11.1b 40.0cd Pyrifluquinazon+Courier 1.6 oz+12 oz 42.2c 7.8bc 24.9e Scorpion 35SL 7 oz 32.8c 9.9c 30.7de Untreated check --- 401.3a 136.3ab 420.2a Table 1. continued Adult SWF / sample Rate amt 1-DAT3 4-DAT3 7-DAT3 Treatment/formulation product/acre 14-Sep 17-Sep 20-Sep Pyrifluquinazon 20SC 3.2 oz 5.3c 29.2c 20.8d Pyrifluquinazon 20SC 1.6 oz 9.8bc 30.9c 25.1d Pyrifluquinazon 20SC 0.8 oz 12.3bc 36.3c 42.8c Courier 40SC 12 oz 83.7a 181.9b 187.2b Pyrifluquinazon+Courier 0.8 oz+12 oz 13.5b 39.9c 32.4cd Pyrifluquinazon+Courier 1.6 oz+12 oz 5.5c 25.2c 21.5d Scorpion 35SL 7 oz 11.2bc 27.9c 33.9cd Untreated check --- 126.2a 380.7a 390.2a Means in a column followed by the same letter are not significantly different (P > 0.05, F-protected LSD). Table 2. SWF Densities (mean /cm ) Rate amt Small Large Total Treatment/formulation product/acre Eggs Nymphs Nymphs Nymphs Pyrifluquinazon 20SC 3.2 oz 5.1cd 20.4ef 3.8b 24.2cd Pyrifluquinazon 20SC 1.6 oz 8.6cd 25.0e 3.7b 28.7c Pyrifluquinazon 20SC 0.8 oz 5.5cd 27.2de 3.8b 31.0c Courier 40SC 12 oz 17.4b 67.7b 7.1b 74.8b Pyrifluquinazon+Courier 0.8 oz+12 oz 4.1c 27.9cd 1.9c 29.8cd Pyrifluquinazon+Courier 1.6 oz+12 oz 3.6cd 21.7de 1.9c 23.6de Scorpion 35SL 7 oz 2.4d 9.4f 2.6c 12.0 Untreated check --- 49.5a 98.0a 33.5a 131.5a Means in a column followed by the same letter are not significantly different (P > 0.05, F-protected LSD). http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Arthropod Management Tests Oxford University Press

EVALUATION OF PYRIFLUQUINAZON FOR CONTROL OF SWEETPOTATO WHITEFLY IN FALL CANTALOUPES, 2012

Arthropod Management Tests , Volume 38 (1) – Jan 1, 2013

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Arthropod Management Tests 2013, Vol. 38 doi: 10.4182/amt.2013.E18 (E18) CANTALOUPE: Cucumis melo L. var. cantalupensis Naudin, ‘Gold Express' EVALUATION OF PYRIFLUQUINAZON FOR CONTROL OF SWEETPOTATO WHITEFLY IN FALL CANTALOUPES, 2012 John C. Palumbo University of Arizona, Yuma Agricultural Center th 6425 W. 8 St., Yuma, Arizona 85364 Phone: (928) 782-3836 E-mail: jpalumbo@ag.arizona.edu Sweetpotato whitefly (SWF): Bemisia tabaci (Gennadius) – biotype B With the loss of endosulfan on melons, this trial was designed to evaluate the efficacy of an experimental foliar insecticide against adult whiteflies in spring melons. Cantaloupe plots planted with ‘Gold Express’ were established at the Yuma Agricultural Center on 16 Aug, 2012 and managed similarly to local growing practices. Plots consisted of a single 84-inch bed, 45 ft long with a 7 ft buffer between each plot. The study was designed as a RCB design with 4 replicates / treatment. The treatment combinations and rates are shown in the tables below. Three foliar spray treatments were applied on 28 Aug, 5 and 13 Sep with a tractor driven CO powered sprayer that delivered 30 gpa at 50 psi, using 4 – TX18 ConeJet nozzles per bed as a broadcast spray. All spray treatments included an adjuvant, DyneAmic at 0.25% vol/vol. Populations of whitefly adults were evaluated at 1, 4 and 7 day intervals following each application (DAT). Adult populations were estimated using a modified vacuum method that employed a 2- gal portable vacuum (DeWALT, Baltimore, MD) which was fitted with cloth-screened 40 Dram containers to capture and retain vacuumed adults. On each sample date, 5 separate plants from each replicate were sampled by vacuuming the terminal area of the plants for 3 s. Containers with adults were taken into the laboratory, placed in a freezer for 24 h after which the number of adults/ plant was recorded. Immature densities were estimated at 7 and 14 days following each application, where 2 leaves were collected from each plant from basal nodes on the primary vine. Leaves were taken into the laboratory where densities of eggs and nymphs were counted on two, 2-cm leaf discs of each leaf using a dissecting microscope. Adult data were averaged at each sample interval, and immature data where averaged across all sample dates. Because of heterogeneity of mean variances, data were log transform (mean+1) and subjected to ANOVA; means were separated using a F-protected LSD (P ≤ 0.05). Actual non- transformed means are presented in the tables. Adult pressure was heavy during this trial. The primary goal of this trial was to evaluate Pyrifluquinazon, a compound with translaminar activity known for its whitefly activity, alone and in combination with Courier for control of both adults and nymphs. Scorpion was included as a commercial standard. Pyrifluquinazon, regardless of rate applied, provided excellent knockdown activity at 1 and 4 DAT compared to the untreated check following each spray application (Table 1). However, nd rd it was only after the 2 and 3 applications that significant residual control of SWF adults at 7 DAT was observed. The addition of Courier did not significantly enhance the adult activity of pyrifluquinazon, however this combination provided significantly better control of nymphs than the Courier used alone (Table 2). As anticipated, Courier did not provide consistent control of adults. For the second consecutive season, Pyrifluquinazon has shown adult whitefly control comparable to the standard. No phytotoxicity was observed. This research was supported by a grant from the California Melon Research Board, PAL-13. Table 1. Adult SWF / sample Rate amt 1-DAT1 4-DAT1 7-DAT1 Treatment/formulation product/acre 29-Aug 31-Aug 4-Sep Pyrifluquinazon 20SC 3.2 oz 20.3c 13.9cd 224.8a Pyrifluquinazon 20SC 1.6 oz 11.8c 9.8d 197.6a Pyrifluquinazon 20SC 0.8 oz 18.0c 24.7cd 195.0a Courier 40SC 12 oz 111.9b 127.6b 243.7a Pyrifluquinazon+Courier 0.8 oz+12 oz 13.8c 13.3cd 210.4a Pyrifluquinazon+Courier 1.6 oz+12 oz 15.1c 21.3cd 202.8a Scorpion 35SL 7 oz 16.4c 15.7cd 220.0a Untreated check --- 230.2a 276.3a 392.1a 1 Arthropod Management Tests 2013, Vol. 38 doi: 10.4182/amt.2013.E18 Table 1. continued Adult SWF / sample Rate amt 1-DAT2 4-DAT2 7-DAT2 Treatment/formulation product/acre 6-Sep 9-Sep 12-Sep Pyrifluquinazon 20SC 3.2 oz 42.9c 5.1c 36.9cde Pyrifluquinazon 20SC 1.6 oz 33.5c 8.1bc 42.5cd Pyrifluquinazon 20SC 0.8 oz 45.6c 9.4c 51.0c Courier 40SC 12 oz 201.8b 90.7a 258.1b Pyrifluquinazon+Courier 0.8 oz+12 oz 43.5c 11.1b 40.0cd Pyrifluquinazon+Courier 1.6 oz+12 oz 42.2c 7.8bc 24.9e Scorpion 35SL 7 oz 32.8c 9.9c 30.7de Untreated check --- 401.3a 136.3ab 420.2a Table 1. continued Adult SWF / sample Rate amt 1-DAT3 4-DAT3 7-DAT3 Treatment/formulation product/acre 14-Sep 17-Sep 20-Sep Pyrifluquinazon 20SC 3.2 oz 5.3c 29.2c 20.8d Pyrifluquinazon 20SC 1.6 oz 9.8bc 30.9c 25.1d Pyrifluquinazon 20SC 0.8 oz 12.3bc 36.3c 42.8c Courier 40SC 12 oz 83.7a 181.9b 187.2b Pyrifluquinazon+Courier 0.8 oz+12 oz 13.5b 39.9c 32.4cd Pyrifluquinazon+Courier 1.6 oz+12 oz 5.5c 25.2c 21.5d Scorpion 35SL 7 oz 11.2bc 27.9c 33.9cd Untreated check --- 126.2a 380.7a 390.2a Means in a column followed by the same letter are not significantly different (P > 0.05, F-protected LSD). Table 2. SWF Densities (mean /cm ) Rate amt Small Large Total Treatment/formulation product/acre Eggs Nymphs Nymphs Nymphs Pyrifluquinazon 20SC 3.2 oz 5.1cd 20.4ef 3.8b 24.2cd Pyrifluquinazon 20SC 1.6 oz 8.6cd 25.0e 3.7b 28.7c Pyrifluquinazon 20SC 0.8 oz 5.5cd 27.2de 3.8b 31.0c Courier 40SC 12 oz 17.4b 67.7b 7.1b 74.8b Pyrifluquinazon+Courier 0.8 oz+12 oz 4.1c 27.9cd 1.9c 29.8cd Pyrifluquinazon+Courier 1.6 oz+12 oz 3.6cd 21.7de 1.9c 23.6de Scorpion 35SL 7 oz 2.4d 9.4f 2.6c 12.0 Untreated check --- 49.5a 98.0a 33.5a 131.5a Means in a column followed by the same letter are not significantly different (P > 0.05, F-protected LSD).

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Arthropod Management TestsOxford University Press

Published: Jan 1, 2013

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