不同品种油菜子粒产量及氮效率差异研究

采用大田试验，以16个冬油菜品种为试验材料，系统研究了油菜子粒产量、氮素吸收量、氮素响应度和氮素利用效率的品种间差异，并初步探讨了氮素吸收效率和氮素利用效率对不同品种油菜氮效率差异的贡献。结果表明，无论施氮水平如何，不同品种的子粒产量、氮素利用效率和氮素响应度均有显著差异，而氮素吸收量只有在不施氮条件下品种间差异才达到显著水平。根据不施氮时的氮效率和氮素响应度将16个油菜品种分为4种不同类型:1）氮高效–高氮响应（NHE-NHR）型，包括Xy1、Xy16、Xy17、Xh19、Xh20和Xy21； 2）氮低效--低氮响应（NLE-NLR） 型，包括Xy6、Xy8和Xy9；3）氮高效–低氮响应（NHE- NLR）型，包括Xy7、Xy12、Xy14、Xy15和Xy24；4）氮低效–高氮响应（NLE-NHR） 型，包括Xy11和Xy13。无论供氮水平如何，氮素利用效率的变异系数均大于氮素吸收效率的变异系数，说明氮素利用效率对油菜氮效率差异的贡献大于氮素吸收效率。但是，氮素吸收效率的变异系数不施氮时大于施氮条件，氮素利用效率的变异系数则相反，说明在氮胁迫条件下，氮效率的差异中来源于氮素利用效率的变异减少，来源于氮素吸收效率的变异增加。

Studies on oilseed yield and nitrogen efficiency in different cultivars of oilseed rape (Brassica napus)

The differences of grain yield, nitrogen absorption amount (NAA), nitrogen response (NR) and nitrogen use efficiency (NUE) among 16 winter cuhivars of Brassica napus were systematically studied, and as well as contributions of nitrogen absorption efficiency (NAE) and NUE to the differences of nitrogen efficiency (NE). Results show that the differences of grain yield, NUE and NR among the 16 winter oilseed rape cultivars are significant under the N fertilizer applications, while the differences of NAA among the cultivars are significant without N fertilizer application. The culti-vats can be divided into four different types based on the NUE and NR under no nitrogen application: 1 ) Nitrogen high effficiency-nitrogen high response (NHE-NHR), including Xyl, Xy16, Xy17, Xh19, Xh20 and Xy21 ; 2) Nitrogen low efficiency-nitrogen low response (NLE-NLR), including Xy6, Xy8 and Xy9; 3) Nitrogen high efficiency-nitrogen low re-sponse (NHE-NLR), including Xy7, Xy12, Xy14, Xy15 and Xy24; 4) Nitrogen low efficiency-nitrogen high response (NLE-NHR), including Xy11 and Xy13. The variation coefficient (VC) of NUE is higher than that of NAE under the N fertilizer applications. It is also showed that the contribution of NUE to NE is higher than that of NAE in oilseed rape. However, VC of NAE under the N fertilizer applications is higher than that without N fertilizer application, and VC of NUE is in reverse. Therefore, it is indicated that under N-stress condition, the differences of NE are from NUE de-creased, and that of NE are from NAE increased.