摘要
【目的】分析施硅对水分胁迫下水稻苗期根系生理生化性状的影响,阐明施硅提高根系抗水分胁迫能力的机理。【方法】采用水培试验,以聚乙二醇(PEG-6000)模拟水分胁迫,以秀水11和巴西陆稻两个水稻品种为材料,研究施硅对根系相关生理生化指标的影响。【结果】施硅能够显著提高PEG诱导的水分胁迫下水稻根系的干物重和相对含水量,并抑制根系过度呼吸消耗。在处理第8天时,与单纯PEG处理相比,施硅使水分胁迫下的秀水11和巴西陆稻根系丙二醛(MDA)含量分别下降了23%和21%,相对电渗透率分别减少了39%和38%,增加了根系质膜的稳定性。施硅还抑制了活性氧的产生、增强了根系抗氧化能力,减缓了根系细胞中脱落酸(ABA)的快速降解。【结论】施硅能减轻水分亏缺所引起的水稻根系生理活性快速下降,从而增强苗期水稻根系对水分胁迫的抗性。
【Objective】 In order to clarify the mechanism of silicon（Si） in enhancing the resistance to water stress,the effects of Si on the physiological and biochemical characteristics of the roots of rice seedlings were investigated under water stress.【Method】 The effects of exogenous Si on the physiological and biochemical parameters of roots of rice [（Oryza sativa ssp.（keng） Ting cv.Xiushui 11） and Brazilian upland rice（O.sativa cv.IAPAR 9）] were investigated under water stress induced by polyethylene glycol（PEG） in hydroponic conditions.【Result】 Exogenous Si could restrain excessive respiration,and increase the dry matter weight and relative water content of the PEG-stressed rice roots.On the 8th day after PEG treatment,the malondialdehyde（MDA） content in the roots of both Si-treated rice cultivars was decreased by 23% and 21%,and the relative electrolyte leakage was decreased by 39% and 38%,respectively,as compared to those of PEG treatment only.Consequently,the plasma membrane stability of the stressed roots was enhanced by Si application.In addition,exogenous Si also increased the root antioxidant defense capacity,slowed down the degradation of abscisic acid（ABA） in rice roots under PEG stress.【Conclusion】 Silicon application could enhance the resistance of rice roots to water deficit stress by preventing the rapid decline of physiological and biochemical activities in roots.
出处
《中国农业科学》
CAS
CSCD
北大核心
2012年第12期2510-2519,共10页
Scientia Agricultura Sinica
基金
国家自然科学基金项目(30600377
31071698
31170405)
中央高校基本科研业务费专项资金项目(QN2011092)
教育部"新世纪优秀人才支持计划"(NCET-11-0441)
关键词
水稻
硅
水分胁迫
根系
rice
silicon
water stress
root
