(B3) PEACH: Prunus persica (L.) GREEN PEACH APHID CONTROL STUDY, 2007 Larry A. Hull Fruit Research and Extension Center Penn State University P. O. Box 330 Biglerville, PA 17307-0330 Phone: (717) 677-6116 Ext. 6 Fax: (717) 677-4112 E-mail:
[email protected] Eric Bohnenblust E-mail:
[email protected] Green peach aphid (GPA): Myzus persicae (Sulzer) Oriental fruit moth (OFM): Grapholita molesta (Busck) A study was designed to evaluate various rates of Movento 240SC against the standard insecticide for GPA control— Provado 1.6F. The treatments were applied to single-tree plots of the cultivar Autumn Glo and each treatment was replicated four times in a randomized block design. The trees were planted to a spacing of 18 x 30 ft and were 11 years old. All treatments were applied with a Durand-Wayland airblast sprayer calibrated to deliver 100 gpa, driven at 2.4 mph. All insecticide treatments were applied on 4 May. No other insecticides were applied until 16 May. All plots received a regular maintenance schedule of fungicides (Indar 75WSP, sulfur). GPA was sampled periodically by counting the number of live colonies found in a 3-min examination of each plot tree. OFM shoot injury was assessed by counting all of the injured shoots per tree at the end of first brood larval development (6 Jun). Data were analyzed with analysis of variance and mean separation using Fisher’s Protected LSD test. Appropriate transformations (e.g., log, square root, arcsin) were used if necessary. Pest pressure was moderate to high throughout the study. On 15 May, both rates of Movento + LI-700, applied on 4 May, failed to significantly reduce GPA when compared to the untreated check (Table 1). The treatments of Provado 1.6F + LI-700 and the high rate of Movento + Stylet Oil provided significant control compared to the untreated check on 15 May (Table 1). After 15 May, all of the treatments significantly reduced GPA below the untreated check. All treatments failed to reduce the incidence of shoots injured by first brood OFM on 6 Jun (Table 1). Table 1. GPA infested shoots/tree Treatment/ formulation
Rate Amt/acre
Movento 240SC + 177.0 ml + LI-700 946.0 ml Movento 240SC + 266.0 ml + LI-700 946.0 ml Movento 240SC + 266.0 ml + Stylet Oil 1892.0 ml Provado 1.6F + 148.0 ml + LI-700 946.0 ml Untreated check ---
Dates of application 15 May
OFM infested shoots/tree
22 May
29 May
5 Jun
6 Jun
4 May
4.5abc
1.8a
0.3a
0.0a
73.5a
4 May
5.5bc
1.0a
1.3a
0.0a
46.3a
4 May
2.8ab
0.3a
1.0a
0.5a
45.3a
0.0a 28.0b
0.0a 15.3b
0.0a 2.0b
75.5a 84.5a
4 May ---
1.0a 10.3c
Means followed by the same letter(s) are not significantly different, (Fisher's Protected LSD, P < 0.05).
