[Objective] This assay was to explore the contribution of enzymes ac- counting for nitrogen reutilization in two Brassica napus varieties No.6 （low nitrogen use efficiency） and No.2 （high nitrogen use efficiency）....
详细信息
[Objective] This assay was to explore the contribution of enzymes ac- counting for nitrogen reutilization in two Brassica napus varieties No.6 （low nitrogen use efficiency） and No.2 （high nitrogen use efficiency）. [Method] We measured the yield, transportation and accumulation of grain nitrogen, loss of leaf nitrogen and ni- trogen use efficiency （NUE） in the two rape varieties, by inhibiting proteolytic en- zyme （PE）, glutamine synthetase （GS） and glutamate synthetase （GOGAT） and la- beling with lSN. [Result] Under GOGAT inhibitor treatment, both of the two varieties presented minimum NUE, yield and nitrogen transportation in grain and maximum ni- trogen loss in leaf. The effect of PE inhibitor was the second greatest, and that of GS inhibitor was the lowest. Moreover, 80% of the nitrogen that had been accumu- lated in leaf was transported out during late growth stage, and 50% to 70% of the grain nitrogen derived from the nitrogen in vegetative organs. The two varieties ex- hibited the same tendency. Rape variety No.2 had higher yield, grain nitrogen accu- mulation and lower nitrogen loss compared with No.6. [Conclusion] GOGAT has the greatest effect on the accumulation of grain nitrogen, yield and nitrogen reutilization in rape. Different enzyme activity may be the major factor resulting in different nitro- gen rautilization in the two rape varieties. Nitrogen stored in leaf during early growth stage is mainly used for nitrogen remobilization. A large proportion of grain nitrogen derives from vegetative tissues.
暂无评论