Incidence of the stemfly, Ophiomyia phaseoli (Tryon) on soybean.
A study was carried out in India on the incidence of Ophiomyia phaseoli (Tryon) on soyabean. Of 782 plants collected at harvest, only 5 were free from infestation by the pest. Of the infested plants, 15% were attacked in the cotyledon stage, 22.37% in the unifoliate stage and the rest in the trifoliate stage. There was a strong negative correlation between the yield and the percentage of stem-length injury, which indicated that with increased stem injury there was a progessive fall in yield. It was also found that with increased stem injury there was a reduction in plant height.