豌豆根对热胁迫的生理响应

目的]探讨豌豆根部对热胁迫的生理响应,进而分析高温对豌豆生长发育影响的生理学基础。方法]通过测定热驯（37℃）、热驯预处理再热胁迫（37~44℃）和直接热胁迫（44℃）的豌豆幼苗根的一些生理指标变化,探讨热胁迫对根生长、细胞膜损伤、膜脂过氧化物和抗氧化剂的影响。结果]热胁迫（44℃）可抑制幼苗根生长,导致相对含水量（RWC）、细胞膜热稳定性（MTS）和抗坏血酸（AsA）含量下降,致使膜脂过氧化产物丙二醛（MDA）含量升高 经37℃热驯预处理再44℃胁迫处理的幼苗的根长、MTS和AsA含量明显高于直接热胁迫处理的。结论]热驯预处理能适当提高豌豆根对后继热胁迫的耐性。高温胁迫对豌豆根部造成的不利影响,将直接影响地上部分的生长发育,进而影响豌豆产量。

Physiological Response of Pea Roots to Heat Stress

Objective] The aim was to discuss the physiological response of pea roots to heat stress so as to analyse the physiological basis for the effect of high temperature on pea growth.Method] The effects of heat stress on root growth,cell membrane damage,membrane lipid peroxidation and antioxidant were discussed through measuring some physiological index change in pea seeding roots under the heat acclimation(37 ℃),heat acclimation pretreatment,then heat stress(37-44 ℃) and direct heat stress(44 ℃).Result] The heat stress(44 ℃) could restrain the growth of seedling roots,result in decreases of relative water content(RWC),cell membrane thermostability(MTS) and ascorbic acid(AsA) in seedling roots,and increase the content of membrane lipid peroxide malondialdehyde(MDA).The root length,the content of MTS and AsA in seedlings with 37 ℃ heat acclimation pretreatment then 44 ℃ heat stress treatment were obvious higher than that with direct heat stress treatment.Conclusion] The tolerance of pea root to succeeding heat stress was properly improved with the heat acclimation pretreatment.The unfavorable effect caused by high temperature stress on pea root could effect the growth and development of aboveground and then affect the yield of pea.