池栽试验条件下,设置渍水、干旱和对照3个水分处理,每个水分处理下设置两个施氮水平,研究了花后渍水或干旱逆境下氮素营养对两个不同类型小麦(Triticum aestivum)品种籽粒产量和品质性状的影响。结果表明,与对照相比,花后渍水或干旱处理显著降低了小麦的千粒重、穗粒数和籽粒产量。在适宜水分和干旱条件下,增施氮肥增加了小麦籽粒产量,而在渍水条件下,增施氮肥降低了产量。干旱处理提高了蛋白质含量,干、湿面筋含量,沉降值和降落值;而渍水处理则降低了小麦籽粒蛋白质含量和干、湿面筋含量。同一水分处理下,增施氮肥提高了蛋白质含量,谷蛋白/醇溶蛋白比,支链淀粉含量和支/直链淀粉比。在小麦籽粒主要品质性状上存在显著的水氮互作效应,且水分、氮肥及水氮互作效应对小麦籽粒产量和品质的影响因品种的不同而异。

Soil water stress is a major ecological factor which limits grain quality formation in wheat. Previous studies have mainly focused on the effects of drought or waterlogging and the interactive effects of nitrogen availability and drought on grain quality, while little information is available on nitrogen supply under waterlogging conditions on grain quality. Therefore, the effects of nitrogen levels on grain yield and quality of two different wheat varieties that differ in grain protein content were compared under drought and waterlogging conditions in a pool culture experiment. Three water treatments, waterlogging, drought (45%-50% of field capacity) and moderate water supply (corresponding to 70%-80% of field capacity), were maintained from anthesis to maturity. Under each water treatment, two nitrogen levels, 120 and 240 kg·hm^-2, were implemented. Both drought and waterlogging significantly reduced 1 000-kernel weight, grain number per ear and grain yield in wheat, compared with moderate water supply (CK). Under CK and drought, nitrogen increased grain yield but reduced yield under waterlogging. Compared with CK, drought increased the contents of protein, dry gluten and wet gluten, SDS-sedimentation volume and falling number, while waterlogging reduced the contents of grain protein, dry and wet gluten. Under the same water treatment, nitrogen increased the protein content, ratio of glutenin to gliadin, amylopectin content and ratio of amylopectin and amylose. Significant interactions between water and nitrogen on glutelin content, amylose content and falling number in the two different wheat varieties were observed. In addition, significant interactions between water and nitrogen on kernel number per spike, contents of albumin and globulin, ratio of glutenin to gliadin, amylopectin content, ratio of amylopectin and amylose and dry gluten in `Xuzhou 26' were observed, but no differences in the `Yangmai 9' were found. Significant interactions on 1 000-kernel weight, total starch content and gluten index in `Yangmai 9' were observed, while no differences in `Xuzhou 26' were found. The effects of water and nitrogen on grain yield and quality varied with different wheat cultivars. These results established the relationship between wheat grain quality with nitrogen under drought or waterlogging conditions. The results of this study offer insights into techniques for resisting stress and regulating high quality wheat under different ecological conditions.