Effects of simulated acidic rainfalls on seed yields of several cultivars of field grown soybean (Glycine max Merrill) were studied under automatically moveable rainfall exclusion shelters.^In the five growing seasons (1981-1985) statistically significant effects of rain pH on yield occurred each year with the Amsoy 71 cultivar.^In almost all bases, the seed yields from Amsoy plants treated with pH 5.6 rain were significantly greater than yields from plants receiving more acidic treatments.^1982 and 1983 experiments did not show any statistically significant reduction in seed yields of the Williams cultivar at acidity levels between pH 5.6 and pH 2.7.^Altering the frequency and duration of the simulated rainfall did alter the yield of the Amsoy and Williams soybean cultivars, while treatment acidity did not.^In 1984 and 1985, the Asgrow 3127, Corsoy 79, and Hobbit cultivars were studied along with Amsoy 71.^The seed yields tended to be reduced when treated with rain simulants with acidity levels between pH 4.4 and pH 3.3, when compared to plants exposed to pH 5.6 rain simulant, but the observed reductions were not always statistically significant at the 95% confidence level.^Studies examining the flowering and pod filling of soybean plants exposed to simulated acid rain were inconclusive for determining the cause of decrease in pod number per plant

"June 1986"--cover. "BNL 52009." "Project Officer: Jeffrey J. Lee, Ecological Effects Division...U.S. Environmental Protection Agency." "Interagency agreement DW89-930196-01."