Pinitol,a larval growth inhibitor forHeliothis zea in soybeans

Summary A search for insect growth inhibitors in methanol extracts of soybean leaves resulted in isolation of pinitol. Pinitol caused a 50% reduction in weight gain (ED₅₀) ofHeliothis zea larvae at about 0.7% when added to a synthetic diet. Although myo-inositol is a normal component of the insect diet, it also caused growth inhibition at higher concentrations; ED₅₀4%.The authors are indebted to R.J. Molyneux for a reference sample of pinitol and to J. Baker for aid with the bioassay. Reference to a company and/or product named by the Department is only for purposes of information and does not imply approval or recommendation of the product to the exclusion of others which may also be suitable.