生物技术通报 ›› 2023, Vol. 39 ›› Issue (7): 160-172.doi: 10.13560/j.cnki.biotech.bull.1985.2022-1253

• 研究报告 • 上一篇    下一篇

褪黑素种子引发处理提高朝天椒耐盐性的作用机制

魏茜雅(), 秦中维, 梁腊梅, 林欣琪, 李映志()   

  1. 广东海洋大学滨海农学院,湛江 524088
  • 收稿日期:2022-10-11 出版日期:2023-07-26 发布日期:2023-08-17
  • 通讯作者: 李映志,男,博士,教授,研究方向:热带园艺植物栽培与育种;E-mail: liyz@gdou.edu.cn
  • 作者简介:魏茜雅,女,硕士研究生,研究方向:热带园艺作物栽培生理;E-mail: 1534536534@qq.com
  • 基金资助:
    广东海洋大学创新强校项目(GDOU2013050217);广东海洋大学创新强校项目(GDOU2016050256)

Mechanism of Melatonin Seed Priming in Improving Salt Tolerance of Capsicum annuum

WEI Xi-ya(), QIN Zhong-wei, LIANG La-mei, LIN Xin-qi, LI Ying-zhi()   

  1. College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang 524088
  • Received:2022-10-11 Published:2023-07-26 Online:2023-08-17

摘要:

褪黑素具有增强植株耐盐性的作用,但其通过种子引发处理提高朝天椒植株耐盐性的效果和作用机制还鲜见报道。为探讨种子引发剂褪黑素(melatonin, MT)对盐胁迫下辣椒幼苗生长及生理特性的影响机制,以‘茂蔬360’为材料,研究褪黑素引发种子对盐胁迫下辣椒幼苗生长、光合特性、抗氧化代谢及渗透调节等的影响。结果表明,褪黑素种子引发处理显著缓解了盐胁迫对朝天椒植株生长的不利影响,与未引发处理相比,经不同浓度褪黑素引发种子后,显著提高了盐胁迫下辣椒幼苗生长,具体表现为植株根长、地上高度、茎鲜重、叶片鲜重、根鲜重、Fv'/Fm'、Qp、NPQ、Fo、Fv/Fm值和叶绿素含量提高。生理分析表明,经不同浓度褪黑素引发处理后,显著降低了盐胁迫下朝天椒植株叶片的丙二醛、过氧化氢和超氧阴离子含量;叶片可溶性糖、可溶性蛋白、脯氨酸、AsA和DHA含量显著提高;叶片POD、SOD、APX和GR活性显著增强。此外,经褪黑素引发处理后,显著提高了盐胁迫下叶、茎、根中K+含量,降低了Na+含量和Na+/ K+值。以上结果表明,100 μmol/L褪黑素种子引发处理效果最好,明显提高了朝天椒对土壤盐分的耐性,减少了植株对Na+的吸收,缓解了盐胁迫对朝天椒植株的伤害。

关键词: 盐胁迫, 朝天椒, 褪黑素, 叶片, 抗氧化, 渗透调节

Abstract:

Melatonin can enhance plant salt tolerance, but its effect and mechanism of improving plant salt tolerance through seed priming are rarely reported. In order to investigate the effects of melatonin(MT)seed priming on the growth and physiological characteristics of pepper seedlings under salt stress, its influences on the growth, photosynthetic characteristics, antioxidant metabolism and osmotic regulation of pepper seedlings under salt stress were studied using ‘Maoshu 360’ as material. The results showed that MT seed priming significantly alleviated the adverse effects of salt stress on the growth of pepper plants. Compared with seed without seed priming treatment, seed priming treatments with different concentrations of melatonin significantly improved the growth of pepper seedlings under salt stress, specifically, these indexes plant root length, above ground height, stem fresh weight, leaf fresh weight, root fresh weight, FV'/Fm', Qp, NPQ, Fo, FV/Fm and chlorophyll content increased. Physiological analysis showed that the contents of malondialdehyde, hydrogen peroxide and superoxide anion in the leaves of pepper under salt stress significantly reduced by seed priming with different concentrations of melatonin. The contents of soluble sugar, soluble protein, proline, AsA and DHA in the leaves significantly increased. The activities of POD, SOD, APX and GR significantly increased. In addition, melatonin seed priming treatment significantly increased the content of K+ in the leaves, stems and roots, and decreased the content of Na+ and Na+/ K+ in the leaves of seedlings under salt stress. The above results showed that 100 μmol/L melatonin seed priming treatment had the best effect, which significantly improved the tolerance to soil salt, reduced the absorption of Na+ by plants, and alleviated the damage of salt stress to plants.

Key words: salt stress, Capsicum annuum, melatonin, leaf blade, anti-oxidation, regulation of osmosis