A Statistical Analysis of Twenty Pollen Spectra from a Single Stratum of Amanda Bog (Ohio)

Author Institution: Department of Botany and Plant Pathology, The Ohio State University, Columbus 1

The Effect of Light on the Growth of Soybean Seedlings

ABSTRACT- During the course of 13 days of germination and growth, the dry weights of roots, hypocotyl, and epicotyl increased in soybeans grown both in the light and in the· dark. The roots of etiolated 13-day-old soybeans were only 50 per cent of the weights of roots from similar plants grown in the light. The epicotyls of etiolated plants were only 18 per cent of the dry weight of epicotyls of light-grown plants, but the hypocoyl weights of etiolated plants were greater than those grown in the light. Cotyledon dry weight of light-grown plants was reduced by 70 per cent during the 13-day period while the cotyledon weight of the etiolated plants was reduced only 60 per cent. Cotyledon removal materially reduced the subsequent growth of soybean seedlings

The Competition of Wild Oats With Wheat, Barley and Oats for Phosphorus and Potassium

Wild oat plants attained the same heights, weights, and P contents when competing with barley, wheat, oats, or other wild oats al both high and low nutrient concentrations. This same relation was found in the K content of wild oats grown with barley and wheat, but wild oats competing with oats contained less K than those competing with wild oats, and this difference was accentuated with increased nutrient concentrations. Barley plants grown in competition with wild oats or with other barley plants showed no effects of competitive interaction al either nutrient concentration. Wheat and oats, like barley, showed no gross growth differences with competing species, but ,both wheat and oats contained more P and K when grown in competition with wild oats than when grown under intraspecific competition. While this interaction was found al both nutrient concentrations, it was more pronounced al the higher one