高温干旱跨代效应对小麦芽期耐旱性和耐盐性的影响

Effects of high temperature and drought intergenerational effects on drought and salt tolerance of wheat at germination stage

选用生长于新疆吐鲁番地区高温胁迫(HT)、石河子地区花后干旱胁迫(DT)以及正常灌溉(NW)环境下收获的‘SDWW-7’、‘津农6号’和‘金石农1号’小麦种子,分别用不同浓度的PEG-6000和NaCl溶液模拟干旱胁迫和盐胁迫,研究来自3种环境条件下收获种子的耐旱性和耐盐性。结果表明:(1)高温干旱胁迫导致父代小麦籽粒千粒重降低,下降幅度为23.55%~46.15%;高温干旱胁迫对‘SDWW-7’和‘金石农1号’的淀粉含量影响存在显著差异(P<0.05)。(2)子代小麦材料在遭受干旱胁迫时,经过高温锻炼后的‘SDWW-7’、‘津农6号’及经过干旱锻炼后的‘金石农1号’长势更好,其相对盐害率的均值仅为1.24%~2.72%。(3)子代小麦材料在遭受盐胁迫时,通过发芽势、发芽率、相对盐害率等筛选指标发现‘SDWW-7’、‘津农6号’、‘金石农1号’在经历高温锻炼后的子代表现最优;两种锻炼方式对子代小麦耐盐性的影响程度表现为‘SDWW-7’>‘津农6号’>‘金石农1号’。(4)子代小麦抗旱性综合评价表明在15%PEG-6000(D1)、20%PEG-6000(D2)干旱胁迫处理下,均为DT环境收获的‘津农6号’、‘金石农1号’子代材料耐旱性最好,位次分别为第1和第7。(5)子代小麦抗盐性综合评价表明在50 mmol·L^(-1)(S1)、100 mmol·L^(-1)(S2)、200 mmol·L^(-1)(S3)盐胁迫处理下,均为HT环境收获的‘SDWW-7’、‘津农6号’、‘SDWW-7’子代小麦耐盐性最好,位次分别为第1、5、11。综上所述,父代经过高温和干旱胁迫锻炼,子代小麦在遭受逆境胁迫时具有更大的发芽优势,表现为父代进行干旱胁迫锻炼可增强子代抗旱性,进行高温胁迫锻炼可增强子代耐盐性,说明该效应能够传递给下一代并且可以增强子代小麦对逆境胁迫的抗性。

Wheat seeds‘SDWW-7’,‘Jinnong 6’and‘Jinshinong 1’were harvested under high temperature stress(HT),post-anthesis drought stress(DT)and normal irrigation(NW)in Turpan,Xinjiang,and the drought and salt tolerance of seeds harvested from three different environments were studied by simulating drought stress and salt stress with PEG-6000 and NaCl solution of different concentrations.The results were as follows:(1)The 1000-grain weight of male wheat decreased by 23.55%~46.15%under high temperature and drought stress,and the effects of high temperature and drought stress on starch content of‘SDWW-7’and‘Jinshinong 1’were different(P<0.05).(2)Under drought stress,‘SDWW-7’,‘Jinnong 6’and‘Jinshinong 1’after heat acclimation grew better with average relative salt damage rate between 1.24%and 2.72%.(3)Under salt stress,the results showed that‘SDWW-7’,‘Jinnong 6’and‘Jinshinong 1’had the best performance after high temperature training,‘SDWW-7’>‘Jinnong 6’>‘Jinshinong 1’showed the effect of two kinds of exercises on salt tolerance of offspring wheat.(4)The comprehensive evaluation of drought resistance of wheat progenies showed that under 15%PEG-6000(D1)and 20%PEG-6000(D2)drought stress,the progenies of‘Jinnong 6’and‘Jinshinong 1’harvested under DT environment had the best drought resistance and ranked 1st and 7th respectively.(5)The comprehensive evaluation of salt resistance of wheat progenies showed that under 50 mmol·L^(-1)(S1),100 mmol·L^(-1)(S2),200 mmol·L^(-1)(S3)salt stress,the salt resistance of wheat progenies was higher than that of wheat progenies,‘SDWW-7’,‘Jinnong 6’and‘SDWW-7’,which were harvested in HT environment,had the best salt tolerance,ranking 1,5 and 11,respectively.In conclusion,after high temperature and drought stress training,the progeny of wheat had a greater germination advantage when subjected to adversity stress,indicating the drought stress training of the paternal generation enhanced the drought resistance of the progeny,and the high temperature stress enhanced salt tolerance of progeny,which suggested that this effect could be passed on to the next generation and improve the resistance of progeny to stress.