Efrects of light and temperature factors on yield and its components in maize

In Shandong Province，by sowing at different stages in different regions，the effect of the difference of light and temperature value under natural conditions on yield and its components was systematically analyzed in maize．The results show that the accumulated temperature and hours of sunshine during the growing period are significantly correlated with the yield and its components．The direct effect of the accumulated temperature is the greatest，the indirect effect of accumulated temperature by sunshine is also the greatest．From flowering to maturity，hours of sunshine affects the grain number per ear obviously．Average diurnal difference of temperature is negatively correlated with thousand-grain weight and yield．Yield and thousand-grain weight decrease from the west to the ease of Shandong Province and the grain number per ear is supreme in the middle of Shandong Province．Accumulated temperatures and sunshine times of high yielding maize during the growing period．and from flowering to maturity are 2500℃ or so and 1150℃ or so ，and 700 hours or so，larger than 300 hours，respectively．