とうもろこしの生育ならびに体内成分の推移に関する研究 第2報 葉身展開に要する積算温度の一定性

抄録

The heat-unit accumulations required for each leaf unfolding of a hybrid corn, Tomorokoshi Ko No. 7,were calculated by using the degrees of various ranges of a daily mean temperature. The fitness of the temperature ranges for leaf unfolding were evaluated by the coefficients of variation for heat-unit accumulations among leaves. The most qualified temperature range, designated as the effective degree range, that had the least coefficient of variation was from 10°C to 27°C and the average of the heat-unit accumulation required for each leaf unfolding in the effective degree range was 36.9°C. The number of heat-units required for the unfolding of a leaf in the effective degrees remained relatively constant for leaves on different nodes, while calendar days varied widely.