【摘要】 分析了甘薯品种不同生长时期光合生理指标的动态变化规律及其与薯干产量之间的关系。结果表明 ,甘薯品种的净光合速率 (Pn)、总叶绿素含量 (Tchl)、叶绿素a含量 (chla)、叶绿素b含量 (chlb)、叶面积系数 (LAI)随生长进程先上升 ,达到最大值 ,然后逐渐下降 ,蔓薯比值 (T/R值 )随生长进程呈下降趋势。薯干产量与各光合生理指标之间的相关性分析表明 ,薯干产量与不同生长期的Pn均呈显著正相关 ,与Tchl,chla,chlb之间有一定的正相关 ,与栽后 90天的T/R值呈显著的负相关 ,与前期和后期的LAI呈正相关 ,而与中期的LAI呈负相关。按对薯干产量的相关程度 ,其排列顺序为Pn ,Tchl,chla,chlb ,T/R ,LAI。甘薯育种应选育净光合速率高、生育后期总叶绿素含量高、T/R值下降快、前期和后期有效叶面积系数大的品种更多还原

【Abstract】 The dynamic variation of various photosynthesis indexes at different growing stages of sweet potato cultivars and their relation to the harvested dry yield of tuber were investigated. Net photosynthetic rate (Pn), total chlorophyll content (Tchl), chlorophyll a (chla), chlorophyll b (chlb) and leaf area index (LAI) went up in the growing process of the plants, reached the maximum value and declined thereafter. The ratio of top to root (T/R ratio) dropped with the growth of the plants. Correlation analysis showed that dry matter yield of the tuber was positively correlated significantly with Pn at various growth stages and to a less degree with Tchl, chla and chlb, and negatively correlated with T/R value 90 d after transplanting. LAI at earlier and later stages of plant growth was positively correlated with dry matter yield of the tuber while that at the middle growth stage showed a negative correlation with it. Based on their significance of correlation with dry matter yield of the tuber, the photosynthesis indexes studied appeared in the order of Pn>Tchl>chla>chlb>T/R>LAI. Therefore, in sweet potato breeding, stress should be placed on the selection for high Pn, high Tchl at later growth stages, rapid decline of T/R value and great LAI at the earlier and later growth stages of the plants.更多还原