干旱胁迫及施加氮素对长春花生物碱的调控

目的:为了阐明不同的干旱条件及氮素水平对长春花叶片中4种生物碱(文多灵、长春质碱、长春碱、长春新碱)含量的影响,为提高长春花生物碱含量提供理论指导。方法:实验设置了CK(对照组即自然生长)、CN(对照+施氮素)、LK(轻度干旱)、LN(轻度干旱+施氮素)、HK(重度干旱)、HN(重度干旱+施氮素)6个处理组,探讨各处理组条件下长春花叶片全氮含量、碱性POD活性、TDC活性、4种生物碱含量的变化特性。结果:轻度干旱条件下POD,TDC的酶活性在处理的整个时期均提高,且胁迫的早期(0～21 d),有利于文多灵、长春质碱、长春碱、长春新碱的积累,后期(28～35 d)反而起抑制作用4种生物碱含量降低。施加外源氮素能有效提高各组长春花叶片中全氮含量、POD和TDC酶活性、文多灵和长春质碱的含量,干旱+施加氮素(LN,HN)处理下有利于长春碱和长春新碱的积累。结论:干旱胁迫及施加氮素对长春花叶片中POD,TDC的活性及4种生物碱的含量均能产生影响,轻度干旱条件下施加氮素(LN)对文多灵、长春质碱、长春碱、长春新碱含量的提高最为显著,是通过全氮含量及酶活性提高来调控的。

Effects of water stress and nitrogen nutrition on regulation of Catharanthus roseus alkaloids metabolism

Objective: Under various drought conditions and nitrogen application, the content of vindoline, catharanthine, vincristine and vinblastine in the leaf of Catharanthus roseus were illustrated to improve the content of alkaloid theoretically. Method: Six groups were set in the experiment, which included: CK(natural control), CN(natural control+nitrogen), LK(low drought), LN(low drought+nitrogen), HK(high drought), HN(high drought+nitrogen) to discuss the change characteristics of total nitrogen, the activity of alkaline POD and TDC, the content of four alkaloids under the different conditions were measured. Result: Under LK condition, the activity of POD, TDC were enhanced.In the early stage of stress (0-21 d), vindoline, catharanthine, vincristine and vinblastine accumulated, and reduced in the later stage (28-35 d).For all groups, adding exogenous nitrogen could improve the total content of nitrogen, vindoline and vinblastine, meanwhile the activity of POD and TDC were enhanced as well. The LN, HN treatments were beneficial to accumulating catharanthine and vinblastine. Conclusion: Drought stress or additional nitrogen have an influence on both of the activities of POD and TDC, and the four alkaloids were affected as well.Thereinto, the LN condition was the most effective treatment for accumulating the four alkaloids (vindoline, catharanthine, vincristine and vinblastine), which were regulated by improve nitrogen content and enzymatic activity.