花后土壤干旱和渍水对不同专用小麦籽粒品质的影响

Effects of Post-Anthesis Drought and Waterlogging on Grain Quality Traits in Different Specialty Wheat Varieties

在温室盆栽条件下,以4个籽粒蛋白质含量不同的小麦基因型为材料,研究了花后土壤干旱(SRWC=45%～50%)、渍水和适宜水分条件(SRWC=75%～80%)下小麦籽粒主要品质特性。干旱显著提高各品种籽粒蛋白质含量、谷蛋白含量及谷蛋白/醇溶蛋白比值,并显著提高面粉干/湿面筋含量。渍水显著降低了籽粒谷蛋白含量及谷蛋白/醇溶蛋白比值。干旱和渍水均显著降低籽粒淀粉产量和支链淀粉含量,直链淀粉含量提高,从而不同程度地降低籽粒直/支链淀粉比。干旱和渍水对各品种籽粒面筋指数、沉降值和降落值的影响因品种而异。与对照相比,干旱和渍水下小麦籽粒各品质性状间的相关性降低,表明土壤水分逆境下各籽粒品质特征值与正常水分条件下差异明显,从而改变了专用小麦的籽粒品质特性。

Four winter wheat (Triticum aestivum L.) genotypes differing in grain protein contents were used in pot culture experiment in greenhouse to investigate the effects of post-anthesis drought (SRWC=45%~50%), waterlogging and moderate soil water status (SRWC=75%~80%) on protein and starch contents in wheat grains. Grain protein content, glutenin content, the ratio of Glu/Gli, dry gluten and wet gluten content increased significantly under drought. Glutenin content and the ratio of Glu/Gli decreased significantly under waterlogging. Under both drought and waterlogging, grain starch yields decreased significantly, and amylose contents increased with decreasing amylpectin contents, consequently led to decreasing ratios of amylose/amylpectin. Drought and waterlogging had differential effects on grain gluten index, sedimentation volume and falling number in accordance with different varieties. Compared with CK, correlation coefficients among grain quality characters in different wheat varieties under drought and waterlogging were lower, indicating that the differences in grain quality characters under drought, waterlogging and moderate soil water status were distinct. These would have impacts on grain quality and utilization values of specialty wheats.