播期对冬小麦品种登海5197群体发育及产量形成的影响

通过大田试验,研究了播期对登海5197群体发育及产量形成的影响。结果表明:(1)播期对拔节前总茎数的影响显著,拔节后不显著。(2)播期推迟一周出苗时间延长一天,基本苗随播期推迟而递减,叶面积系数第二播期(10月15日)最高,总茎蘖数和有效茎蘖数随播期推迟而降低,但有效茎蘖率和成穗率呈相反趋势。(3)对籽粒产量形成的R ichards解析表明,第二播期比第一播期(10月8日)和第三播期(10月22日)灌浆启动较早,最大灌浆速率和起始势较高,但活跃灌浆期较短。(4)群体和单株干物质积累量在开花前表现为随播期的推迟而明显减少,开花后由于第二播期的单株干物质积累加快,成熟期第二播期的群体干物质最高。(5)随播期的推迟,穗数和千粒重逐渐降低,穗粒数和籽粒产量呈先上升后降低趋势,最高产量出现在第二播期。

Effect of Sowing Date on Population Development and Yield Formation of Winter Wheat Cultivar Denghai 5197

A field trial was conducted to reveal the effect of sowing date on the population development and the yield formation of Denghai 5197.The results were as follows.Firstly,the effect of sowing date on the total stem number was significant before stem elongation,but not significant after stem elongation.Secondly,the emergence time postponed one day once the sowing date postponed one week,and also the basic seedlings,the total stem & tiller number and the effective stem & tiller number declined,while the effective stem & tiller rate and spike rate increased.The leaf area index of the second sowing-date treatment was the highest.Thirdly,the analysis by Richards' model showed the wheat of the second sowing date reached the maximum grain-filling rate earlier than those of the first and third treatments,and the maximum grain-filling rate and starting potential of the second sowing date were higher,while its active grain-filling period was shorter.Fourthly,the dry matter accumulation of the population and individual deceased obviously with the sowing date postponing before anthesis.The population dry matter of the second sowing date was the highest in maturity,as a result of the accelerated accumulation of the individual dry matter.Fifthly,the spike number and 1000-grain weight deceased,and the grain number per spike and grain yield increased firstly and then decreased with the sowing date postponed,the maximum yield occurred at the second sowing time.