油菜是我国主要的植物油料作物之一，干旱是限制甘肃省油菜产业发展的主要因素之一，春季油菜苗期干旱日益严重。采用盆栽法模拟春季干旱，对不同品种油菜苗期的生物量和根系进行观察。结果表明，苗期连续10 d干旱、土壤含水量低于5.76%时油菜幼苗出现死亡现象，土壤含水量减少约50%。甘蓝型油菜的水分利用率和根冠比均高于白菜型和芥菜型油菜，芥菜型油菜最低；根系鲜重与含水量和水分利用效率呈正相关关系。说明甘蓝型油菜抗旱性强于白菜型和芥菜型，且杂交品种陇油10号和青杂5号抗旱性比常规品种陇油2号强。

Rapeseed is one of the main plant oil crops in China， and drought is one of the main factors restricting the development of rapeseed industry in Gansu Province. Spring seedling drought of rapeseed is increasingly serious. The potted plants method was used to simulate spring drought， the biomass and root system of different rapeseed cultivars at seedling stage were observed. The results showed that the seedlings died when the seedling stage was drought for 10 days and the soil moisture content was lower than 5.76%， and the soil moisture content decreased by about 50%. The water use efficiency and root-shoot ratio of Brassica napus were higher than those of Brassica campestris and Brassica juncea， and Brassica juncea was the lowest. Root fresh weight was positively correlated with water content and water use efficiency. The results indicated that drought resistance of Brassica napus was higher than that of Brassica campestris and Brassica juncea， and the drought resistance of hybrid cultivars Longyou 10 and Qingza 5 was higher than that of conventional cultivar Longyou 2.

S565.4

甘肃省青年科技基金计划 (18JR3RA259)；甘肃省油料作物创新团队(2017GAAS22)。