品种和播种密度对小麦灌浆特性及产量影响的研究

Effects of Cultivars and Sowing Densities on Grain Filling Characteristics and Yield

研究了不同品种和播种密度对籽粒鲜重和干重变化过程及产量和构成因子的影响。试验结果表明，小麦开花后籽粒鲜重变化过程拟合方程：ｙ＝ａ＋ｂｘ＋ｃｘ２＋ｄｘ３。扬麦５号、扬麦１５８籽粒鲜重增加最快时间分别为花后１６ｄ、２０ｄ，达到鲜重最大时间分别为花后３０ｄ、３５ｄ。花后籽粒干重的增加过程拟合Ｌｏｇｉｓｔｉｃ曲线（ｙ＝ｋ／（１＋ａｅ－ｂｘ）。籽粒干重增加过程分为渐增期（花后０～１２ｄ）、快增期（花后１２～２７ｄ）、缓增期（花后２７～３７ｄ）。不同播种密度通过调节籽粒灌浆速率和灌浆历期而显著影响粒重。本试验条件下。

Effects of cultivars and sowing densities on grain fresh weight,dry weight,yield and its components were studied.The increasing process of grain fresh weight after anthsis could be described in the equation of =a+bx+cx 2+dx 3.The fastest increase of grain fresh weight of Yangmai 5 and Yangmai 158 was attained at 16th d,20th d,after anthesis,resp.,while highest fresh weight attained at 30th d,35th d after anthesis,resp..The increasing process of grain dry weight after anthesis could be modeled in a logistic curve [=k/(1+ae -bx )].Grain growth process was divided into 3 stages,i.e.gradually increasing stage (0 to 12 d after anthesis),fast increasing stage (12～27 d after anthesis),slow increasing stage (27～32 d after anthesis).The sowing density could significantly regulate filling rate and duration and finally affected grain weight.Suitable sowing density of the 2 cultivars was 120×10 4 to 210×10 4 basic seedlings per ha this experiment condition.