低剂量60co-γ辐照对拟南芥幼苗耐热性的影响-植物学专业毕业论文.docx

AB STRACT
Hi曲temperature is one of the major limiting factors that affect plant the cellular level, heat stress differentially affects the stability of various proteins,fluidity of membrane lipids,RNA synthesis anization of cytoskeleton,and inhibits activities of metabolic injuries lead to reduced ion flux,metabolic imbalance,accumulation of toxic by-products,such as reactive oxygen
species(ROS),and eventually starvation and inhibition of have showed that gamma irradiation at low doses can stimulate growth and development,alleviate the damage,and enhance the tolerance to environmental stress in ,the knowledge regarding the mechanisms underlying
the enhanced tolerance induced by low-dose gamma irradiation is far from fully understood.
In this study。we use model plant Arabidopsis as research materials to investigate the physiological and molecular mechanisms of heat stress alleviated by low-dose gamma ,the Arabidopsis seeds were exposed to a range of gamma rays before subjected to heat treatment,and the growth of Arabidopsis thaliana seedlings under heat stress Was results showed that in response to heat stress,the low-dose gamma irradiation(25-75 Oy)significantly increased the germination index,root length,survival rate,and fresh pared with ,gamma ray treatment with a dose of 50 Gy exhibited maximal heat tolerance in terms of the overall growth pared with other ,we used seeds that were irradiated with the dose of 50 Oy for the subsequent studies.
Abiotic stress usually stimulates the production of reactive oxygen species and lipid order to reveal the redox state of Arabidopsis seedlings,we use the colorimetric analysis method to determine the production rate of super oxygen anion(02D,concentration of H202 and MDA level in control(0 Gy)and 50 Gy gamma-irradiated samples in response to heat resuRs showed that the producti