Response of Soybeans to Temperature Under High Light Intensities

Differential growth responses were observed for soybeans subjected to day temperatures from 18 to 36 C under controlled greenhouse conditions at high light intensities. Leaf area production reached a maximum at 27–30 C, whereas maximum dry matter accumulation was obtained at 36 C. Specific leaf weight varied with temperature and was greatest at the high and low temperature regimes. Stem elongation was greatest at 36 C, and axillary growth was most evident at low temperatures. Except at the very early stages, about 50% of the dry matter accumulation occurred in the leaf blades, irrespective of the temperature.