Soybean looper

Johnson, SJ USDA To determine the resistance by soybean looper insects to methyl parathion and permethrin. 

Glycine max Coumestrol, phaseollin, afrormosin Soybean looper (Pseudoplusia 375,... 

The antiherbivory effects of phytoalexins have been studied in our laboratory using the Mexican bean beetle and the soybean looper (44). The Mexican bean beetle, Epilachna varivestis. is an oligophagous species that feeds preferentially on legume hosts. 

Table V. Soybean Looper Survival and Weight Gain to...

To test the validity of the bioassay itself we prepared a diet containing increasing amounts of rotenone, a compound derived from isoflavones and thus chemically not far removed from the soybean phytoalexins. Results in this case followed exactly the expected dose response curve (Table VII). Both survival and weight gain of larvae were drastically affected by increasing concentrations of rotenone. This experiment showed that the bioassay would be capable of detecting toxic effects of the phytoalexins on the soybean looper larvae, if such effects were acute. It showed also that the detoxification mechanisms in the soybean looper, a rather polyphagous insect, may permit it to adequately overcome the antibiotic effect of the isoflavonoid phytoalexins, but not that of the isoflavone rotenone. 

Table VII. Soybean Looper Survival and Weight Gain to 8 Days on Artificial Medium + Rotenone (Our Unpublished Data).

Ramachandran, R. and Norris, D. M. (1991). Volatiles mediating plant-herbivore-natural enemy interactions electroantennogram responses of soybean looper, Pseudoplusia includens, and a parasitoid, Microplitis demolitor, to green leaf volatiles. Journal of Chemical Ecology 17 1665-1690. 

The utility of this new procedure has been demonstrated by the synthesis of mus-calure, the sex pheromone of the house fly Musca domestica) (Eq. 68)I22) and dis-parlure, the sex pheromone of the Gypsy moth (Porthetria dispar L.)123), and the sex attractant of soybean loopers (Pseudoplusia includens)124>. 

Sowbugs, 324,324 barriers for, 442 mulches for, 444 nematodes and, 457 Soybean, trap crops and, 440 Soybean loopers, viral pathogens for, 461 Speck... 

Chelators have been shown to synergize the insecticide trans -permethrim by preventing its hydrolysis in the soybean looper (70). The enzyme is clearly not a typical esterase as it contains a metal group. The authors did not add excesses of various metal ions to show that they could suppress the synergism this would show that the compounds actually acted as chelators in their system. 

It is clear that the insecticide of interest must be used to assay for this type of resistance since 1-naphthyl acetate, a general substrate used to stain for many hydrolases, did not detect malathion carboxylester hydrolase (assayed as the hydrolysis of [14C]-malathion) in starch gel electrophoresis of Culex tarsalis (23). Similarly, trans-permethrin hydrolyzing activity of soybean looper was resolved from 1-naphthyl acetate hydrolyzing activity by polyacrylamide gel electrophoresis (28). Malathion carboxylester hydrolases were not correlated with activity toward 1-naphthyl acetate in Drosophila, Anopheles, and Indianmeal moth (25.29.30). 

Direct effects on soybean seed and grain quality are typically associated with pod or seed feeders, which include various stink bugs, corn earworm, bean leaf beetle, grasshoppers, several armyworms, and occasionally high population densities of soybean looper and velvetbean caterpillar (Steffey et al., 1994 Turnipseed, 1976 Hammond et al., 1991 Zeiss Klubertanz, 1994). 

Hart S V, Kogan M, Paxton J D 1983. Effect of soybean phytoalexins on the herbivorous insects Mexican bean beetle and soybean looper. J Chem Ecol 9 657-672... 

Mitchell (597) has discussed the feasibility of using multicomponent formulations for control of several important pests of field crops. Hendricks et al. (600) showed that a mixture of looplure (622) and virelure (623, 624) were compatible and caught the cabbage looper (T. ni), the soybean looper (Pseudoplusia includens), and the tobacco budworm (H. virescens) on the same traps. It seems likely that pesticide applications to field crops could be greatly reduced by means of pheromone-baited monitoring traps, and such efforts will undoubtedly become a part of the integrated pest management projects now established by the Extension Service of the USDA. 

Another company (624, 625) supplies a controlled release dispenser, which is a three-layer plastic laminated sheet consisting of a bottom protective layer, a middle pheromone reservoir layer, and a top permeable layer through which the pheromone diffuses. The sheet can be cut into ribbons and applied over an area. Formulations have been field tested on a number of insect pests gypsy moth, pink bollworm, peachtree borer, lesser peach tree borer, soybean looper, cabbage looper, European elm bark beetle, tobacco budworm, fall armyworm, tussock moth, eastern spruce budworm, and Mediterranean fruit fly. 

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