谷氨酰胺对扬麦9号强势和弱势籽粒淀粉及蛋白质积累的调控

Effects of Different Concentrations of Glutamine in Culture Solution on Accumulation of Starch, Protein and Their Components in Superior and Inferior Grains of Wheat Ears Cultured in Vitro

离体穗培养条件下,研究了培养基中不同谷氨酰胺供应水平对冬小麦品种扬麦9号强势和弱势籽粒粒重以及淀粉和蛋白质及其组分积累的影响。结果显示,弱势籽粒的蔗糖和氨基酸含量均较强势籽粒高,而其积累量均较强势籽粒低,可见弱势籽粒中同化物贮存量较强势籽粒少,其合成淀粉和蛋白质的能力较强势籽粒低。在一定范围内提高谷氨酰胺供应水平可显著促进弱势籽粒淀粉和蛋白质的积累,提高弱势籽粒粒重,可见一定范围内改善氮素营养有利于弱势籽粒物质积累;但相同谷氨酰胺浓度下强势籽粒淀粉、蛋白质和氨基酸积累量均高于弱势籽粒,强势籽粒四种蛋白组分的积累量均较弱势籽粒高。4和6 g／L谷氨酰胺处理下,强势和弱势籽粒淀粉、蛋白质及氨基酸含量的差异小于其他较高或较低谷氨酰胺浓度。强势籽粒清蛋白和球蛋白含量略低于弱势籽粒,而醇溶蛋白和麦谷蛋白在2-6 g／L时高于弱势籽粒,但差异较小。

In vitro ear culture experiment was conducted to determine the effects of different concentrations of glutamine in culture solution on grain weight, accumulation of starch, protein and their components in superior and inferior grains in winter wheat cv. Yangmai 9. Contents of sucrose and amino acid were higher in inferior grain than that in superior grain, while accumulation amounts of sucrose and amino acid were lower in inferior grain than that in superior grain. It seemed that assimilative sink of inferior grain were smaller than that of superior grain, and the ability of sucrose converting to starch and amino acid coverting to protein of inferior grain were weaker than that of superior grain. The single grain weight and amounts of starch and protein accumulated in inferior grains exhibited single-peak curves with increasing glutamine concentrations from 2 g/L to 6 g/L. It showed that increasing nitrogen supply within a reasonable range could improve the dry matter accumulation of inferior grain. Under the same concentrations of glutamine, the amounts of starch, protein and amino acid as well as the four protein components accumulated in superior grains were higher than those in inferior grains. Differences in contents of starch, protein and amino acid between the superior grains and inferior grains were smaller under the glutamine concentrations of 4 g/L and 6 g/L in culture solution than under the lower or higher concentrations. The contents of albumin and globulin were slightly lower in superior grains than those ininferior grains, whereas the contents of gliadin and glutenin were slightly higher in superior grains than those in inferior grains with the glutamine supply increasing from 2 g/L to 6 g/L.