定西半干旱地区水分条件对春小麦幼穗分化的影响

Influence of Water Conditions on the Differentiation of Spikelets of the Spring Wheat in the Semi arid Area of Dingxi

对定西地区不同水分条件下春小麦幼穗分化进行观察研究，结果表明：春小麦幼穗发育受水分条件影响显著。水分作用的关键时期是小穗形成期，且伸长期和单棱期对水分最敏感（ｒ伸降水＝０７４９、ｒ单降水＝０７６９）。水分主要通过影响小穗密度（ｒ＝０７２８）和退化小花率（ｒ＝０６９５）来影响小穗数和成花数。

Effect of water condition on differentiation of spikelets of spring wheat in the semi arid area of Dingxi was studied. The results showed that differentiation of spikelets was influenced significantly by water conditions. The spikelets forming stage was an important period. The spikelets were sensitive to water stress in elongation stage and single prismatic stage( r e p = 0 749 , r s p = 0 769 ). The number of spikelets and formed flowers were affected through the spikelets density ( r =0.728) and retrogression ration ( r = 0.695) which influenced mainly with water.