氮胁迫对红麻生理生化特性及干茎产量的影响

【目的】探讨红麻亲本及其子代耐低氮能力的差异,为耐低氮红麻品种的筛选及其遗传改良提供理论依据。【方法】以红麻不育系P3A、恢复系992及子代F1为材料,设置不施氮（N0）和正常施氮（N＋）两个处理,通过盆栽试验,研究氮胁迫对红麻苗期主要生理生化特性及其产量的影响。【结果】正常施氮（N＋）条件下,亲本的茎、叶水分含量、叶绿素含量和氮、磷、钾含量均高于F1,但硝酸还原酶活性及单株干茎产量均低于F1;在不施氮（N0）条件下,F1的茎叶水分含量、叶绿素含量、硝酸还原酶活性、氮含量降幅均比亲本小,而磷、钾含量增幅比亲本高;氮胁迫下,参试红麻植株茎叶水分和氮含量、硝酸还原酶活性、叶绿素含量均下降,而植株茎叶磷、钾含量均有所提高。【结论】在正常施氮（N＋）条件下,F1生长势更强,单株干茎产量更高;在不施氮（N0）条件下,F1表现出较强的耐低氮生理特性,抗逆境优势强于亲本,因此F1适宜推广选种。

Effect of nitrogen stress on physio-biochemical characteristics and dry stem yield of Hibiscus cannabinus L.

[Objective]The present study was conducted to provide a theoretical basis for authenticating the tolerance of parents and filial generations of Hibiscus cannabinus L. to low N-fertilization during the seedling stage. [Method]The male sterility line P3A, restorer line 992 and their first filial generation F1 were treated with N （N＋） and without N （N0） fertilizer in a pot culture experiment to investigate their main physio-biochemical characteristics and dry stem yield at seedling stage. [Result]The plants treated with N＋ showed higher water, chlorophyll and the N, P, K content in leaf and stem of parents than in that of F1, however, the nitrate reductase activity and dry stem yield of parents were lower than those of F1 plants. In N0 treatment, the reduction in water and chlorophyll content, nitrate reductase activity and N content in leaf and stem of F1 were less, and P and K contents in F1 were higher compared to the parents. In N＋ treatment, the contents of water, N and chlorophyll, nitrate reductase activity in leaf and stem of tested Hibiscus cannabinus L. plants were lower, while the contents of P and K were higher compared to the control. [Conclusion]The growth and yield of F1 were stronger and higher than parents with N＋ treatment. F1 showed stronger tolerance to low N stress compared to parents. Therefore, F1 crossed by P3A and 992 was suitable for cultivation and extension.