不同水分条件下冬小麦的水分利用效率、产量和可溶性糖含量

以我国北方12个冬小麦品种(系)和美国德州3个冬小麦品种(系)为材料,在甘肃陇东黄土高原旱作和拔节期有限补灌条件下,研究了不同基因型小麦之间产量、水分利用效率(WUE)和灌浆期穗下节可溶性糖含量的差异。结果表明:不论旱作还是有限补灌,不同基因型冬小麦之间产量、WUE、穗下节可溶性糖含量均存在明显差异,随着灌浆过程的进行穗下节可溶性糖含量呈先升高后降低的变化趋势,灌浆中后期达到最大。小麦穗下节可溶性糖含量在旱作条件下高于有限补灌。在2008年9月至2009年6月生育期降雨较常年减少1/3,属于严重干旱年份,小麦灌浆初期和中期穗下节可溶性糖含量与籽粒产量和水分利用效率无明显相关性,但到灌浆中后期和后期却达到显著相关;小麦拔节期补灌100mm水分后,不同基因型小麦表现出明显的水分补偿或超补偿效应,并且灌浆期穗下节可溶性糖含量与产量、WUE均呈显著正相关,并在灌浆中后期和后期达到极显著相关。因此,旱地冬小麦灌浆中后期和后期穗下节可溶性糖含量可作为筛选高效用水品种的参考指标之一。

WATER USE EFFICIENCY, GRAIN YIELD AND SOLUBLE SUGAR CONTENT OF WINTER WHEAT UNDER DIFFERENT WATER CONDITIONS

The differences of grain yield, water use efficiency (WUE) and stem soluble sugar (SSS) content under spike in various genotypes of dryland winter wheat were studied with fifteen winter wheat genotypes (twelve from North China and three from Texas, America) in Loess Plateau of east Gansu under dryland and supplemental irrigation condition at jointing stage. The results showed that different genotypes had considerable differences in grain yield, WUE and SSS whether under dryland or irrigated condition. The SSS increased with grain filling proceeding, reached the maximum at mid-late filling stage, and then declined. Moreover, the SSS under dryland condition is higher than it under limited irrigation condition. Growing-season rainfall of Sep.2008 to Jun 2009 decreased by one third,which was the severe drought year, the correlation between SSS with grain yield and WUE is not significant at early and middle grain filling stages but is significant at late grain filling stage under dryland condition. With irrigation of 100 mm water at jointing stage, various genotypes of winter wheat had significant compensation or super compensation effects, and highly positive correlations of SSS related to grain yield and WUE were obtained under limited irrigation condition, especially after mid-late grain filling stage. Therefore, the SSS can be used by breeding programs as a potential selection criterion for grain yield and WUE in wheat.