硝酸还原酶抑制剂钨酸钠对油菜硝态氮积累的影响

采用溶液培养方法,选取硝酸盐积累差异明显的两个油菜品种（低硝态氮积累品种‘红油3号’和高硝态氮积累品种‘中双6号’,研究苗期根系硝酸还原酶（NR）活性被抑制以后两个油菜品种叶片、叶柄和根系中NR活性和硝态氮含量的变化。结果表明：1.0mmol.L-1的NR活性抑制剂Na2WO4对两个油菜品种的根系NR活性抑制效果最佳;根系NR活性被抑制以后,两个油菜品种的根系NR活性、硝态氮吸收速率均显著下降,而硝态氮含量却显著上升;且Na2WO4对‘中双6号’硝态氮吸收的抑制程度强于其对‘红油3号’的抑制。叶片和叶柄的NR活性变化不显著,但叶柄硝态氮含量显著下降,叶片硝态氮含量稳定,且这一趋势在低积累品种‘红油3号’中表现得更为明显。

Effects of Nitrate Reductase Inhibitor Na_2WO_4 on Nitrate Accumulation in Oilseed Rape

A soilless culture（nutrient solution） experiment was conducted to study the effects of nitrate reductase inhibitor Na2WO4 on nitrate reductase（NR） activity and NO3--N content in some organs（including root,leaf,petiole） of two different cultivars（high nitrate-N accumulation type ＇Zhongshuang 6＇ and low nitrate-N accumulation type ＇Hongyou 3＇） oilseed rape（Brassica napus L.） at seedling stage.Results showed that the most appropriate concentration of Na2WO4 was 1.0 mmol·L-1;Na2WO4 significantly decreased NR activity and NO3--N absorption rate in the root of oilseed rape comparing with the control（CK）,however,significantly increasing in NO3--N content.High nitrate accumulation type ＇Zhongshuang 6＇ had higher inhibiter efficiency comparing with low nitrate accumulation type ＇Hongyou 3＇.There were no significant difference on NR activity in leaf and petiole with or without Na2WO4,in contrast,Na2WO4 significantly decreased NO3--N content in the petiole of oilseed rape,and NO3--N content in the leaf was almost stable under it treatment,especially in ＇Hongyou 3＇.