不同基因型冬小麦冠层温度与产量和水分利用效率的关系

通过研究水分利用效率和产量之间的相关性,证明冠层温度在筛选小麦品种(系)时也是一个重要的指标。利用红外测温仪,于2006-2007年在甘肃陇东旱原研究了来自中国北方和美国的40个小麦品种(系)不同生育时期冠层温度的差异及其与产量、水分利用效率的关系。结果表明,不同基因型小麦在籽粒灌浆结实期存在着冠层温度高度分异现象,其分异程度随生育期的推后明显加大,到灌浆中后期达到最大。无论拔节期、灌浆初期还是中后期,旱地冬小麦产量、水分利用效率与冠层温度均呈极显著的负相关,并且随着生育期推移,相关性增大。灌浆中期以后不同基因型小麦冠层温度保持较高的一致性,冠层温度偏低的品种具有较高的产量和水分利用效率。灌浆中后期的冠层温度在评价小麦产量和水分利用效率上具有较高的可靠性,可作为田间选择的一个指标应用。

RELATIONSHIP BETWEEN CANOPY TEMPERATURE WITH GRAIN YIELD AND WATER USE EFFICIENCY IN VARIOUS GENOTYPES OF WINTER WHEAT

Canopy temperature(CT) has been considered as a physiological indicator of plant fitness,and can be used as an effective index in screening wheat(Triticum aestivum L.) for water use efficiency(WUE) and high yield.Field studies were conducted to examine the differences in CT and the relationships between CT with grain yield and WUE of forty winter wheat genotypes(collected from north China and America).The results showed that different genotypes showed considerable differences in CT,and the differences increased with the development of plant,the maximum differences was observed at mid-late grain filling stage.Among the genotypes studied,a highly negative correlation between CT with grain yield and WUE was established,throughout the grain filling stage and the negative correlation increased as grain filling proceeded.These results clearly indicated that the same genotypes maintained a consistent CT after middle grain filling,and those genotypes with high yield and WUE had low CTs,whereas the genotype with low yield and WUE genotypes had high CTs.It is suggested that CT at mid-late grain filling stage can be used as a parameter to estimate yield and WUE.