水分胁迫对白三叶物质分配和根系生长的影响

通过抗旱性能不同的2个品种的栽培对照试验,研究了水分胁迫对白三叶Triflium repen干物质分配、碳水化合物积累、脯氨酸含量和根系分布的影响.结果表明:土壤水分变化首先影响到生物量在植物不同器官的分配,即累积性的CO2净同化产物的分配,白三叶能够通过提高匍匐茎、根系的干物质分配比例来回避干旱.同时,在干旱胁迫发生时,植株内可溶性糖含量和脯氨酸含量都大幅度增加,根系生长状况发生改变.然而,不同品种又表现出不同的特性,抗旱品种通过增加可溶性糖、脯氨酸含量提高渗透势及增加深根数量的能力显著大于抗旱性差的品种.

Effects of water stress on dry matter allocation and root growth of white clover

The effects of water stress on dry matter allocation,carbohydrate accumulation,proline content and root distribution in two white clover varieties were studied by pot experiment.The result indicated that soil moisture change affected biomass distribution in different organs,i.e.,accumulative CO2 assimilation distribution.White clover could escape drought by increasing dry matter distribution in stolon and root system.Meanwhile,both soluble sugar and proline content increased and root system growth changed under water stress.Different varieties showed different characteristics,compared to drought sensitive variety,the drought resistant variety showed higher capacity in terms of increasing soluble sugar and proline content to increase infiltration,as well as increasing deep root number.