播期推迟对冬小麦产量形成和籽粒品质的调控效应

为了明确推迟播期对小麦产量形成和品质的影响,选用2个冬小麦品种(轮选987和京冬8号),在大田条件下研究了播期推迟对小麦群体动态、物质积累、产量构成和籽粒品质的调控效应.结果表明,播期推迟能显著降低小麦冬前分蘖数,促进春季分蘖的发生和成穗,提高分蘖成穗率.播期对小麦植株干物质积累的影响存在基因型差异.播期推迟引起小麦产量构成因素的变化,进而导致籽粒产量下降,且京冬8号出现显著下降时对应的播期早于轮选987.播期推迟后小麦籽粒中的淀粉含量呈下降趋势,蛋白质含量呈上升趋势,同时二者的主要组成成份也随之改变.因此,冀东地区选用轮选987且适当早播(10月5日播种)可以获得高产；推迟播期至10月10日则籽粒品质提高,但要注意加强小麦生育后期的田间管理,防止粒重明显降低.

Regulating Effect of Delayed Sowing Date on Yield Formation and Grain Quality of Winter Wheat

In order to further clear the regulating effect of sowing date on grain yield and quality of winter wheat in Jidong area, two representative wheat cultivars of Lunxuan 987 (LX987) and Jingdong 8(JD8) were selected, and three sowing dates (Oct. 5, 10 and 15) were designed to study the effects of delayed sowing dates on dynamic changes of population size and dry matter accumulation, yield and its composition, and grain quality under field conditions. The results showed that the number of tillers per plant before winter significantly decreased, but spring tillers greatly increased and easily developed to spikes, so that tiller survival rates enhanced when sowing dates were postponed under the conditions of this study. Effects of sowing dates on the dynamic changes of dry matter accumulation per plant varied with wheat genotypes. Wheat yield components were unfavorably changed when sowing dates were postponed, so the grain yield decreased.The sowing time that the yield of JD8 was significantly reduced was earlier than that of LX987. Delayed sowing date reduced starch content of wheat grain, improved protein content of wheat grain, and changed their components as well in this study.Therefore, LX987 was selected, and it should be sowed early (Oct. 5) for higher yield in Jidong area. The sowing date of LX987 might be postponed to Oct.10 to meet for the requirement of local wheat maize double cropping system, as it might decline wheat grain yield, but improve quality. At the same time, field management had to be strengthened to avoid a big kernel weight decline for delayed sowing wheat stand.