Evaluation of Safer's™ Insecticidal Soap as 

 a Management Tool in Apple Orchards 



Craig Hollingsworth and William Coli 



Departments of Entomology, University of Massachusetts 



Joseph Sincuk 



Department of Plant & Soil Sciences, University of Massachusetts 



While second-stage apple IPM is directed toward 

 eliminating chemical interference with the apple eco- 

 system, remedial pesticides are still required to correct 

 some orchard problems. Ideally, these pesticides 

 should have as little negative environmental impact as 

 possible. Further, as a defense against pesticide resis- 

 tance, it is also desirable to have available a range of 

 pesticides which use different modes of action. These 

 properties have been ascribed to insecticidal soap. 



This study was established to compare Safer's™ 

 Insecticidal Soap with standard orchard pesticides 

 under commercial apple growing conditions. Materials 

 were tested against common apple foliage pests, spirea 



aphid, Aphis spiraecola (Patch), and European red 

 mite (ERM), Panonychus ulmi (Koch). In addition, the 

 effects of these materials on the aphid predators, 

 Aphidoletes aphidimyza Rondani (Diptera: 

 Cecidomyiidae) and Syrphus spp± (Diptera: Syrphidae) 

 were examined. 



Methods Used 



The study was conducted at the University of 

 Massachusetts Horticultural Research Center in Bel- 

 chertown, MA on two apple cultivars, Mcintosh and 

 Delicious. Four treatments were arranged in a ran- 



1.0 



8 0-8- 



.E o.7 -- 

 tn 



§2 0.6- 

 o 



■2 0.5- 



1 0.4-- 



o 



■-£ 0.3- 



o 



Q-0 2-- 



o V - J -^- 



£ 0.1 -- 

 0.0- 



Spirea aphid 



EZH Thioda 



F553 Thioda 



■■ Soap 



i Z i Soap 



n (/full rate) 

 n (half re 



(full rate) 



(half 



rate) plus Soap (full rate) 

 rate) 



> 



a 



</ 



5' 

 a 



^ 



26 Jun 29 Jun 6 Jul 

 Mcintosh 



26 Jun 29 Jun 6 Ju 

 Red Delicious 



Figure 1. Proportion of leaves infested with spirea aphid. Treatments were applied on June 27. There were 

 no differences among means for each date and cultivar. 



Fruit Notes, Spring, 1990 



21 



