施氮对油菜籽粒和果壳中氮素积累的影响

Effects of nitrogen fertilization on nitrogen accumulation of seeds and shell in rapeseed cultivar Yangyou 4(Brassica napus L.)

通过定期测定4种不同施氮量条件下油菜籽粒和果壳中氮素含量,研究籽粒和果壳中氮素积累动态。结果表明：①籽粒中氮素积累动态可用Richards方程拟合（R^2=0.9970^＊＊～0.9995^＊＊）。②前期籽粒氮素积累的持续时间占总时间的50%～60%,积累量占总量的30%～40%,两者均随施氮量的增加而减少。中期和后期氮素积累的持续时间均占总时间的20%～25%,积累量分别占总量的50%～55%和10%～15%,均随施氮量的增加而增加。③籽粒中氮素积累总量随施氮量增加而增加,其增量的70%和30%分别在中期和后期形成。④果壳中的氮素积累量呈先增加后减少的变化趋势,并随施氮量的增加而增加。

The trials were carried out in 2003-2004 to investigate the nitrogen accumulation of seeds and shell through measuring the nitrogen content under four nitrogen levels. The main results were as follows. ① The Richards equation could be used to describe the process of nitrogen accumulation in seed （R^2 = 0. 997 0^＊＊ - 0. 999 5^＊＊）. ② The ratio of nitrogen accumulation time and amount in early stage was 50%-60% and 30%-40%, respectively. Both of them decreased with the increasing of nitrogen application. In middle and late stage, the ratio of nitrogen accumulation time was all about 20%-25% and the amount was 50%- 55% and 10%-15%, respectively. They all increased with the increasing of nitrogen application. ③ The total amount of nitrogen accumulation in seeds increased with the increasing of nitrogen application. 70% of the increased nitrogen accumulated in middle stage and 30% in late stage. ④ The amount of nitrogen accumulation in shell increased firstly and then decreased under different nitrogen levels, and increased with the increasing of nitrogen application at the same stage.