不同施肥水平对青稞籽粒灌浆期淀粉与蛋白积累特性的影响

Effects of Fertilizer Application Rate on the Dynamics of Starch and Protein Accumulation in Hulless Barley Grain During Grain Filling Period

为提供更合理的施肥依据,促进青稞的优质高产,以QTB13、QTB25和藏青27这3个青稞品种(系)为材料,研究不同施肥水平(0、90、180、270、360 kg/hm^2,且质量比N︰P=1︰0.6)下,3个青稞品种(系)灌浆期籽粒中淀粉和蛋白质含量的积累动态。结果表明,随灌浆进程的推进,3个青稞品种(系)籽粒的直链淀粉、支链淀粉和总淀粉的含量均呈增加的趋势;蛋白质含量均呈先降低后升高再降低然后又升高的趋势,在花后21 d最低,其中QTB13和QTB25在F2处理(施肥水平180 kg/hm^2)下最高,藏青27在F3处理(施肥水平270 kg/hm^2)下最高。本结果说明增加施肥量降低了青稞籽粒的淀粉含量,增加了蛋白质含量,而过量施肥则会降低蛋白质含量。

This study was aimed to determine appropriate fertilizer application rates for achieving high quality and high yields in hulless barley production practice.We investigated the dynamics of starch and protein contents in hulless barley grains at grain filling stage.A field experiment was carried out with different fertilizer application rates(0,90,180,270,and 360 kg/hm^2;the ratio of N to P = 1︰0.6),using the three hulless barley cultivars(or lines)’QTB 13’,’QTB 25’,and ’Zangqing 27’ as experimental materials.The results showed that the contents of amylose,amylopectin,and starch in grains of the three hulless barley cultivars increased with time during the grain filling stage.The protein contents in the grains of three hulless barley cultivars all decreased first and then increased;such drop-rise trend occurred again with the advance of the grain filling stage;and the protein contents were the lowest at 21 days after anthesis.The contents of amylose,amylopectin,and starch in the grains of the three hulless barley cultivars all declined with elevating fertilizer application rate,while the protein contents in them rose first and then dropped with increasing fertilizer application rate.The fertilizer application rate at 180 kg/hm^2 led to the highest protein content in the grains of ’QTB 13’ and ’QTB 25’,while the fertilizer application rate at 270 kg/hm^2 resulted in the highest protein content in grains of ’Zangqing 27’.Overall,an increase in fertilizer application rate led to a drop in starch content,but a rise in protein content in grains of the hulless barley cultivars.