Effect of Soil Temperature on Infectivity and Development of Rotylenchulus reniformis on Resistant and Susceptible Soybeans, Glycine max.

The effect o f soil temperature on parasitism and development of Rotylenchulus reniformis on resistant ('Peking' and 'Custer') and susceptible ('Hood' and 'Lee') soybean (Glycine max) cultivars was studied. Soil temperatures of 15, 21.5, 25, 29.5 and 36 C +/- 1 C were maintained in temperature tanks in a greenhouse. R. reniformis developed best at 25 and 29.5 C. The female life cycle can be completed within 19 days after inoculation under favorable conditions at 29.5 C. Plant root growth was best at 21.5 C. During a 27-day period, no egg masses were present on nematodes feeding on roots grown at 15 and 36 C. Egg masses developed on Hood but not on Lee when nematodes were introduced into soil and maintained at 29.5 C for 2 days before raising the temperature to 36 C.