水稻孕穗期干旱对籽粒性状的影响

孕穗期干旱导致水稻籽粒的体积、长、宽、厚、长／宽、干粒重等性状发生改变。在干旱或正常栽培条件下，不同水稻品种籽粒体积的大小主要由该品种的粒长与粒宽所决定，籽粒长宽值越大，则体积越大；但干旱年理后某一品种籽粒长、宽、厚的相对变化率则均对该品种籽粒的体积变化有显著影响，且籽粒宽度的相对变化率对该品种粒体积变化的影响最大，籽粒厚度的相对变化率对其影响最小。在正常栽培条件下，水稻籽粒何种与千粒重成显著正相关，但干旱处理后二者的相关性有所下降，相关不显著。

Effects of Drought on Rice Grain Indices at Booting Stage

Drought at booting stage varies the rice grain indices such as volume, length, width, thickness, length/width, and weight of 1000 grains. In drought or suitable condition, the grain volume of different rice varieties is mainly determined by its grain length and width. But after drought the relative changed ratio of a rice variety's grain length, width, thickness affects its grain volume significantly. The effects of grain width's relative changed ratio to grain volume is the largest, the effects of grain thickness' relative changed ratio to grain volume is the smallest. At suitable condition the correlation between grain volume and weight of 1000 grain is significant, but after drought the correlation between them decreases to insignificance.