Study on acquired thermotolerance in rice seedlings _ | 水稻幼苗获得性耐热性研究_____

Chinese. ［目的］研究水稻幼苗获得性耐热性诱导过程中的生理生化变化。［方法］以水稻幼苗为材料，设置45 ℃高温胁迫、35 ℃高温驯化90 min后于25 ℃恢复120 min，再进行45 ℃胁迫120 min 2种处理方法，研究高温驯化对水稻幼苗耐热性以及幼苗根、茎生长、细胞膜透性、相对含水量、叶绿素含量、可溶性蛋白含量、可溶性糖含量的影响。［结果］ 45 ℃高温导致水稻根和茎的生长受到抑制，相对电导率、相对含水量、叶绿素含量、可溶性蛋白以及可溶性糖含量下降。35 ℃高温驯化能够减轻水稻幼苗根、茎生长抑制和膜损伤程度，并使相对含水量、叶绿素含量、可溶性蛋白和可溶性糖含量维持在相对较高水平，水稻幼苗耐热性得到提高。相对电导率、相对含水量、叶绿素含量、可溶性蛋白和可溶性糖含量可考虑作为该水稻品种苗期耐热性的鉴定指标。

English. ［Objective］ The aim was to study physiological and biochemical changes during acquired thermotolerance induction in rice seedlings. ［Method］ Effect of high temperature acclimation on root and stem growth, membrane thermostability, relative water content, chlorophyll content and soluble protein content and soluble carbohydrate content under 45 ℃ treatment or 35 ℃ acclimation for 90 min followed by recovery for 120 min at 25 ℃ and then under 45 ℃ treatment for 120 min, respectively, were investigated. ［Result］ Results showed that 45 ℃ high temperature resulted in suppress of root and stem growth and reduction of relative water content, chlorophyll content, soluble protein content and soluble carbohydrate content whereas increase in membrane permeability. 35 ℃ acclimation induced thermotolerance increase by keeping higher level of relative water content, chlorophyll content, soluble protein content and soluble carbohydrate content while alleviated root and stem growth repression and membrane damage. Relative water content, chlorophyll content and soluble protein content and soluble carbohydrate content and membrane permeability might be used as physiological thermotolerance indicators of rice. _