低温胁迫后水分对水稻幼苗根系活力和水孔蛋白相关基因表达的影响  

Effects of Moisture Content on Root Vigor and the Expression of Aquaporin-related Genes in Rice Seedlings Under Low Temperature Stress

作　　者：黄奇娜[1] 江苏 汪利民 张燕 俞林飞 李春福 丁利群 邵国胜[1] HUANG Qina;JIANG Su;WANG Limin;ZHANG Yan;YU Linfei;LI Chunfu;DING Liqun;SHAO Guosheng(China National Rice Research Institute,Hangzhou 310006,China;Agriculture and Rural Affairs Bureau of Kaihua County,Zhejiang Province,Kaihua 324300,China)

机构地区：[1]中国水稻研究所,杭州310006 [2]浙江省开化县农业农村局,浙江开化324300

出　　处：《中国水稻科学》2022年第4期367-376,共10页Chinese Journal of Rice Science

基　　金：中央级公益性科研院所基本科研业务费专项(CPSIBRF-CNRRI-202121);中国水稻研究所所级重点研发项目(CNRRI-2020-05)。

摘　　要：【目的】为了探究低温冷害胁迫后水分/湿度对水稻幼苗根系活力和水分运输等的影响,【方法】以具有低温耐性差异的嘉籼7号和辐8329两个水稻品种为研究材料进行低温胁迫处理后,在正常温度培养条件下进行实验Ⅰ(不同湿度梯度,正常温度培养条件下)和实验Ⅱ(快速回温处理实验,以正常温度恢复为对照)。【结果】实验Ⅰ结果表明,与较低湿度(30%)相比,较高的湿度(60%和90%)可以提高根系活力,有效保证水稻幼苗的存活率并缓解其遭受的低温冷害。水孔蛋白基因OsPIP2;5和OsPIP2;6的表达水平与根系活力密切相关,对水稻的抗寒和低温耐性具有显著的调控作用。实验Ⅱ结果表明,与对照组(CK)相比,快速回温处理后水稻幼苗的含水量和根系活力显著降低;且正常自然恢复状态下,两个水稻品种的存活率明显高于快速回温组幼苗。【结论】低温胁迫显著影响水稻幼苗的生长发育过程。较高的湿度环境有助于缓解幼苗的低温冷害损伤,保证存活率。同时,低温胁迫后的外界环境湿度对水稻幼苗的含水量、根系活力和水孔蛋白相关基因表达有显著影响,其中OsPIP2;5和OsPIP2;6的表达水平与根系活力正相关,在水稻幼苗抵御外界低温冷害过程中起重要作用。因此,与低温胁迫后田间大量灌溉相比,正常温度下土壤缓慢的温度上升对幼苗的根系活力影响较小,有助于其在低温冷害后恢复生命活动。【Objective】The purpose of this study is to explore the effects of moisture content or humidity on root vigor and water transport of rice seedlings under low temperature stress.【Method】Two rice cultivars(Jiaxian 7 and Fu 8329)with different chilling tolerance were used as materials.Experiment I(humidity 30%,60%and 90%)and experimentⅡ(quick rewarming experiment)were carried out.【Result】Compared with lower humidity(30%),higher humidity(60%and 90%)could effectively increase the root vigor,ensure the survival rate of rice seedlings and alleviate the chilling injury.The expression level of OsPIP2;5 and OsPIP2;6 were closely related to root vigor,which had a significant regulatory effect on cold tolerance of rice.Compared with normal rewarming treatment(CK),the water content and root vigor of rice seedlings were decreased after quick rewarming treatment.The survival rate in CK was significantly higher than in the quick rewarming experiment.【Conclusion】Low temperature stress affects the growth and development of rice seedlings.After chilling injury,high humidity can alleviate the damage and ensure the rice survival rate.Humidity environment after low temperature stress significantly influenced the water content,root vigor and the expression levels of genes related to aquaporin.The expression levels of OsPIP2;5 and OsPIP2;6 were positively correlated with root vigor,and played an important role in resistance to cold injury of rice seedlings.Therefore,compared with large-scale irrigation in the field after low temperature stress,the slow soil temperature rise had less effect on root vigor and can help rice seedlings to restore their life activities.

关 键 词：水稻 低温胁迫 基因表达 根系活力 水孔蛋白 水分含量 

分 类 号：S51[农业科学—作物学]