不同氮素水平对盐胁迫下菘蓝幼苗生长和活性成分的影响
时间:2018-11-12 19:09 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：目的：探究不同氮素水平对盐胁迫下菘蓝幼苗生长和活性成分的影响。方法：以河北保定栽培的菘蓝为试验材料，在100 mmol•L-1NaCl胁迫下，分别以3. 75(T1) 、7. 5 (T2) 、15 (T3) 、18. 75(T4)、22.5 mmol•L-1( T5) 5个不同的氮素水平进行处理，并以不含盐的正常氮素水平（15 mmol•L-1）处理为对照（CK），测定不同氮素水平对盐胁迫下菘蓝的幼苗生长、保护酶及氮代谢关键酶活性、脯氨酸含量和活性成分积累的影响。结果：盐胁迫下，随着氮素水平的升高，菘蓝幼苗的叶和根的干重及鲜重先升高后降低，低氮( T1、T2)和过高的氮素(T5)处理下菘蓝叶片中的SOD、POD、CAT活性及脯氨酸含量降低，MDA含量升高。随着氮素水平的升高，盐胁迫下菘蓝体内NR及GS的活性先升高后下降，硝态氮、可溶性糖、可溶性蛋白质、游离氨基酸和（R,S）-告依春含量在T4处理时最高。结论：盐胁迫下，适当的氮素水平能够有效的提高菘蓝幼苗的生物量、抗氧化酶活性及菘蓝的渗透调节能力；并提高了氮代谢关键酶的活性及硝态氮的利用率，促进菘蓝体内可溶性糖、可溶性蛋白质、游离氨基酸和（R,S）-告依春的积累。综合分析，T4处理能够有效缓解盐胁迫对菘蓝幼苗生长的危害，促进活性成分的积累。30134 毕业论文关键词：菘蓝；氮素水平；盐胁迫；幼苗生长；活性成分 Effects of different nitrogen levels on seedling growth and active components of Isatis indigotica Fort. under salt stress Abstract： Objection: To explore the effects of different nitrogen levels on seedling growth and active components of Isatis indigotica Fort. under salt stress. Method: The Hebei baoding cultivation population at the seedling stage were used as materials. The changes of seedling growth, protective enzyme and nitrogen metabolism enzyme activities, protine contents and accumulation of active ingredients were investigated by supplying with different nitrogen levels (T1:3.75 mmol•L-1, T2:7.5 mmol•L-1, T3:15 mmol•L-1, T4:18.75 mmol•L-1, T5:22.5 mmol•L-1) under 100 mmol•L-1NaCl stress, and the normal nitrogen level(15 mmol•L-1) without salt was taken as the comparison(CK). Result: It was demonstrated that the fresh and dry weights of leaf and root of I. indigotica seedling initially increased and then decreased. Both the lower (T1 and T2) and much higher (T5) nitrogen application under salt stress could decrease the activities of antioxidant enzymes-SOD, POD, CAT and protein contents, while increase the MDA contents in I. indigotica leaves. Conclusion: The appropriate nitrogen application could promote the biomasses, antioxidant enzyme activities and osmoregulation abilities of I. indigotica under salt stress. Besides, it could also improve the accumulation of soluble sugar, soluble protein, free amino acid and epigoitrin. In conclusion, the appropriate nitrogen application (T4) could release the harm of salt stress to the I. indigotica seedling growth and promote the accumulation of active components. Key words: Isatis indigotica Fort.; nitrogen level; salt stress; seedling growth; active component 目 录 摘要 1 关键词 1 Abstract 1 Key words 2 引言 2 1 材料与方法 3 1．1 试验材料与方法 3 1．2 测定项目与方法 3 1．2．1 生物量的测定 3 1．2．2 抗氧化酶活性的测定 3 1．2．3 丙二醛（MDA）含量的测定 3 1．2．4 脯氨酸含量的测定 3 1．2．5 活性成分的测定 3 1．2．6 氮代谢关键酶活性和硝态氮含量的测定 3 (责任编辑：qin) |