(A1) APPLE: Malus domestica Borkhausen, ‘Oregon Spur Delicious’ Elizabeth H. Beers Tree Fruit Research & Extension Center 1100 N. Western Ave. Wenatchee, WA 98801 Phone: 509-663-8181 ext 234 Fax: 509-662-8714 E-mail: email@example.com Randy R. Talley E-mail: firstname.lastname@example.org San Jose scale (SJS): Quadraspidiotus perniciosus (Comstock) The purpose of this test was to find new materials to replace organophosphate insecticides for control of SJS. The experiment was conducted in a 29-yr-old ‘Delicious’ research orchard near Orondo, WA. The trees were planted to a spacing of 10 × 18 ft. Plots consisted of three rows of seven to nine trees per row, with four buffer rows between treated rows. The experimental design was a RCB with four treatments and six replicates. Pesticide applications were made with an Rears Pak-Blast sprayer at three timings: delayed dormant (6 April; 200 gpa), delayed petal fall (23 May; 100 gpa) and about 2 wk later (8 June; 100 gpa). Scale crawlers were sampled with sticky bands placed around scaffold limbs (three bands per plot). The bands consisted of 3-in wide strips of heavy-duty aluminum foil with a bead of Tanglefoot in the center to trap the crawlers. The bands were placed in the orchard in late May, and collected ca. weekly throughout the season until mid-September. Fruit were evaluated in mid-September by examining 80-290 fruit/plot, the variable crop load in this block making it difficult to obtain even numbers. Fruit were rated as clean (no scale), low (1-5 scales); moderate (6-30 scales); or high (> 30 scales). Data were analyzed using ANOVA and treatment means were separated using the Fisher’s LSD. st All treatments suppressed the 1 generation of crawlers in comparison to the check (Table 1). Significant differences in st crawler counts were found on five dates, mostly in the 1 generation; very few crawlers were found during the second generation. The seasonal sums of crawlers caught in sticky bands were not significantly different among treatments, despite the substantial numerical difference. The degree of fruit infestation corresponded to the number of crawlers found in the treatments (Table 2). The check had the highest percentage of scale-infested fruit, while the delayed dormant oil followed by two applications of Ultor + oil had the lowest levels of fruit infestation. The other two treatments were intermediate (numerically), however, the best treatment was not significantly different from oil at delayed dormant alone. Table 1. SJS crawlers/cm sticky band Rate (amt)/ Treatment/ acre or - Seasonal x x x x formulation % vol/vol Timing 4-Jun 11-Jun 18-Jun 25-Jun 2-Jul 9-Jul 16-Jul 23-Jul 30-Jul 13-Aug 27-Aug 10-Sep sums WE Dormant Oil 1.5% DD 0.42a 0.07a 0.02b 0.02b 0.01b 0.00b 0.00a 0.00a 0.00 0.00a 0.13a 0.00a 1.99a Ultor 150SC + 14 fl oz PF, PF + 14 Saf-T-Side oil 0.25% v/v Ultor 150SC + 14 fl oz PF, PF + 14 0.74a 1.05a 0.03ab 0.14ab 0.04b 0.00b 0.12a 0.00a 0.02 0.12a 0.00a 0.00a 6.61a Saf-T-Side oil 0.25% WE Dormant Oil 1.5% DD 0.52a 0.56a 0.02b 0.19ab 0.10b 0.00b 0.00a 0.00a 0.00 0.04a 0.02a 0.00a 4.06a Check 0.98a 4.89a 2.06a 2.68a 1.63a 0.41a 0.00a 0.00a 0.00 0.14a 0.00a 0.02a 37.91a WE, Wilbur-Ellis Dormant Oil. DD, delayed dormant (6 April; 200 gpa), delayed petal fall (23 May; 100 gpa); + 14, 14 days after delayed petal fall (8 June; 100 gpa). Means within columns not followed by the same letter are significantly different, Fisher’s LSD. Data transformed log(x + 0.5) due to unequal variances. Table 2. Treatment/ Rate - amt/ % SJS-infested formulation acre or % vol/vol Timing fruit Wilbur-Ellis Dormant Oil 1.5% DD 13.4c Ultor 150SC + 14 fl oz PF, PF + 14 + Saf-T-Side oil 0.25% v/v Ultor 150SC + 14 fl oz PF, PF + 14 25.5ab + Saf-T-Side oil 0.25% v/v Wilbur-Ellis Dormant Oil 1.5% DD 16.67bc Check 39.3a DD, delayed dormant (6 April; 200 gpa), delayed petal fall (23 May; 100 gpa); + 14, 14 days after delayed petal fall (8 June; 100 gpa). Means within columns not followed by the same letter are significantly different, Fisher’s LSD. Data transformed arcsine(sqrt(proportion infested)) due to unequal variances.
Arthropod Management Tests – Oxford University Press
Published: Jan 1, 2008