盐胁迫过程中渗透胁迫和离子胁迫对水稻种子萌发的影响  

Effects of Osmotic Stress and Ion Stress on Rice Seed Germination during Salt Stress

作　　者：聂佳俊 白璐嘉 韦云飞 马启林 Nie Jiajun;Bai Lujia;Wei Yunfei;Ma Qilin(College of Tropical Crop,Hainan University,Haikou,570228)

机构地区：[1]海南大学热带作物学院,海口570228

出　　处：《分子植物育种》2022年第3期959-966,共8页Molecular Plant Breeding

基　　金：国家自然科学基金项目(31660381);海南省重大科技计划项目(ZDKJ202001);国家科技支撑计划项目(2015-BAD01B02-1-1)共同资助。

摘　　要：种子萌发是植物生长发育的关键阶段,易受外界环境的影响,研究水稻种子萌发响应不同胁迫的生理机制具有重要意义。本研究以水稻品系‘58L’种子为实验材料,用NaCl (100 mmol/L)溶液及等渗透势的PEG和PEG+LiCl溶液和低渗透势但同等离子毒性的Li Cl (20 mmol/L)溶液分别进行胁迫处理,对种子萌发过程中的发芽特性、形态特征、生理指标及活性氧的分布进行了观察测定和分析。结果表明:各胁迫处理均会不同程度地抑制或延缓水稻种子的萌发,其中以PEG和PEG+LiCl处理最为明显,其次为NaCl处理,LiCl的影响最小,故渗透胁迫是影响种子发芽势的主要因素;对于幼苗的形态建成,PEG处理主要影响芽的生长,LiCl主要抑制根的生长,Na Cl和PEG+LiCl则对根、芽生长都有明显抑制;在种子萌发早期,NaCl和LiCl对α-淀粉酶活性的影响较小,PEG处理的影响则比较明显,随着处理时间延长,NaCl、LiCl和PEG+LiCl处理下α-淀粉酶活性增加缓慢,而PEG处理下α-淀粉酶活性在后期迅速增加,甚至高于对照,表明PEG只是影响种子吸水导致α-淀粉酶活性暂时受到抑制。本研究表明盐胁迫条件下渗透胁迫和离子胁迫对水稻种子发芽和形态建成具有不同影响,为揭示逆境下种子萌发的机理和进行技术调控提供理论依据。Seed germination is a critical period of plant growth and development, which is easily affected by environment. Therefore, it is of great significance to study the physiological mechanism of rice seed germination under different stresses. In this study, the seeds of rice variety ’58 L’ were treated with NaCl(100 mmol/L) solution,iso-osmotic PEG and PEG+Li Cl solution and low osmotic potential but the same ionic toxicity LiCl(20 mmol/L)solution. The germination characteristics, morphological characteristics, physiological indexes and the distribution of reactive oxygen during seed germination were observed and analyzed. The results showed that different stress treatments could inhibit or delay the germination of rice seeds in different degrees, among which PEG and PEG+LiCl treatment were the most obvious, followed by NaCl treatment, and LiCl had the least effect, so osmotic stress was the main factor affecting seed germination energy. In terms of morphological formation of seedlings,PEG treatment mainly affected the growth of buds, LiCl mainly inhibited the growth of roots, while NaCl and PEG+LiCl significantly inhibited the growth of roots and buds. In the early stage of seed germination, NaCl and Li Cl had little effect on the activity of α-amylase, while the effect of PEG treatment was more obvious. With the extension of treatment time, the activity of α-amylase increased slowly under NaCl, LiCl and PEG +LiCl treatment, while the activity of α-amylase increased rapidly in the later stage under PEG treatment, even higher than that of the control, indicating that PEG only temporarily inhibited α-amylase activity by affecting seed water absorption. This study showed that osmotic stress and ion stress had different effects on rice seed germination and morphogenesis under salt stress, which provided a theoretical basis for revealing the mechanism of seed germination and technical regulation under stress.

关 键 词：水稻 发芽 盐胁迫 渗透胁迫 离子胁迫 

分 类 号：S511[农业科学—作物学]