施氮量对弱筋小麦籽粒品质形成的影响

Effect of Nitrogen Rate on Grain Quality of Weak Gluten Wheat

为明确施氮量对弱筋小麦籽粒产量与品质形成的影响,以弱筋小麦品种扬麦13和宁麦13为材料,设置不同施氮量(纯氮0、105、210和315kg·hm^-2)处理,分析了施氮量对弱筋小麦籽粒蛋白质及其组分含量、淀粉粒度分布与黏度参数的影响。结果表明,两个弱筋小麦品种的籽粒蛋白质及其组分含量均随施氮量增加而增加;与醇溶蛋白相比,氮肥对谷蛋白含量的影响较大。当施氮量为105kg·hm^-2时,小麦籽粒蛋白质含量分别为10.59%(扬麦13)、11.37%(宁麦13),达到弱筋小麦标准要求;施氮量为210kg·hm^-2时,两个小麦品种的蛋白质含量均超过12.5%。增施氮肥能有效提高弱筋小麦籽粒灌浆中后期谷氨酰胺合成酶(GS)活性。在施氮0~210kg·hm^-2时,增施氮肥可提高B型(<10μm)淀粉粒体积、表面积百分比,降低A型(>10μm)淀粉粒体积、表面积百分比。施氮量对弱筋小麦B型、A型淀粉粒数目百分比无显著影响。淀粉峰值黏度、最终黏度在施氮0~210kg·hm^-2范围内均随施氮量增加而增高。本试验条件下,要保证弱筋小麦籽粒品质和相对较高的产量,更为适宜的施氮量应在105~210kg·hm^-2之间。

The objective of the study was to investigate the effect of nitrogen rate on grain yield and quality of weak gluten wheat.The weak gluten wheat cultivars Ningmai 13 and Yangmai 13 were used as test materials and four nitrogen rates(0,105,210 and 315 kg·hm^-2)were set up,to study the influence of nitrogen levels on grain yield,protein content,starch granule size distribution and viscosity parameters in weak gluten wheat.The results showed that the protein content and its components of weak gluten wheat increased with the increase of nitrogen application rate,and the effect of nitrogen fertilizer on glutenin content was greater than that on gliadin.When the nitrogen application rate was 105 kg·hm^-2,the grain protein of the two weak gluten wheat varieties were 10.59%(Yangmai 13)and 11.37%(Ningmai 13),respectively,which met the standard requirements of weak gluten wheat.Nitrogen application effectively increased the activity of GS enzyme in the middle and late grain filling of weak gluten wheat.When nitrogen application was 0-210 kg·hm^-2,the volume and surface area percentage of starch granules of B type(<10μm)were increased with the increase of nitrogen application,while those of A type(>10μm)were decreased.Nitrogen application rate had no significant effect on the number distribution of starch granules in weak gluten wheat.The peak viscosity and final viscosity of starch increased with the increase of nitrogen application rate in the range of 0-210 kg·hm^-2.Under the conditions of this experiment,to ensure the grain quality of weak gluten wheat with relatively high grain yield,the suitable nitrogen application rate should be between 105 with 210 kg·hm^-2.