[Response of grain filling characteristics of maize to sowing date.].

To study the effect of different sowing dates on the process of grain filling characteristics, Jingke 528 (JK528) and Zhengdan 958 (ZD958) were used in the field experiment with two sowing dates (10th April and 14th May). The results showed that the 100-grain dry mass and yield of JK528 and ZD958 with the early spring sowing were significantly higher than that with the spring sowing date, which increased by 6.8% and 10.

[Dynamic characteristics of leaf area index and allocation characters of ecological resources for different yielding spring maize populations].

By using 3-year field experimental results and related meteorological observation data, the dynamic characteristics of leaf area index (LAI) and the allocation characters of ecological resources for different yielding spring maize (Zea Mays L.) population in Huadian of Jilin Province were studied. The results showed that the dynamic characteristics of relative LAI, with the relative growth days of test population, relative effective accumulated temperature, relative sunshine hours and relative rainfall as independent variables, fitted rational formula y = (a + bx) /(1 + cx + dx2), and the regression equation of maize yield with the ratios of growth days before and after silking (x1), effective accumulated temperature before and after silking (x2), rainfall before and after silking (x3), and sunshine hours before and after silking (x4) was y = 5465.