【摘要】 以4个玉米(Zea mays L.)品种——‘郑单958’(耐干旱)、‘浚单20’(耐高温)、‘隆玉602’(耐干旱高温复合胁迫)和‘驻玉309’(对3种胁迫均敏感)为实验材料,分别采用脱落酸(ABA)及其抑制剂氟定酮(F)、H2O2及其清除剂碘化钾(I)和丙酮酸钠(P)预处理,探讨干旱高温复合胁迫下小热休克蛋白(sHSPs)在不同耐旱性玉米品种中的表达以及ABA和H2O2对其表达的影响。结果显示:(1)高温、干旱高温复合胁迫诱导的sHSP16.9、sHSP17.2、sHSP17.4、sHSP17.5、sHSP22和sHSP26等6个sHSPs基因表达增加量明显高于干旱和对照。(2)在6个sHSPs中,sHSP17.2基因仅在‘郑单958’中表达;sHSP16.9、sHSP17.4和sHSP26基因在‘隆玉602’中表达增加量最高,在‘驻玉309’中表达增量最低;sHSP17.5和sHSP22基因在‘郑单958’中表达增加量最高,在‘驻玉309’中最低。(3)ABA、F、I和P预处理后,对干旱高温复合胁迫诱导的6个sHSPs基因表达增加量仅有略微影响,但显著影响了sHSP26的蛋白表达。研究表明,sHSPs在不同耐旱性玉米品种中的表达存在显著差异,ABA和H2O2仅稍微提高了sHSPs基因表达,但显著提高了sHSP26蛋白表达,这些结果为进一步研究植物在多胁迫条件下耐逆机理奠定了基础。更多还原

【Abstract】 In order to determine the difference of small heat shock protein(sHSPs)expression in four maize(Zea mays L.)varieties with different endurance under combined drought and heat stress,and the effect of abscisic acid(ABA)and H2 O2 on their expression,we used‘Zhengdan 958’with drought endurance,‘Xundan 20’with heat endurance,‘Longyu 602’with endurance to combined drought and heat stress,‘Zhuyu 309’with sensitiveness to three stresses as experimental material.ABA and ABA synthesis inhibitor Flu(F),H2 O2 scavenger KI(I)and sodium pyruvate(P)were used to study the influences of ABA and H2 O2 on sHSPs expressions induced by combined drought and heat stress in maize leaves.The results were as follows:(1)The increases of six sHSPs such as sHSP16.9,sHSP17.2,sHSP17.4,sHSP17.5,sHSP22 and sHSP26induced by heat stress and combined drought and heat stress were all more than that induced by control and drought;(2)sHSP17.2 was only expressed in‘Zhengdan 958’,while the increase of sHSP16.9,sHSP17.4and sHSP26gene expression was all the highest in‘Longyu 602’,but the lowest in ‘Zhuyu 309’among four maize varieties;the increase sHSP17.5and sHSP22gene expression was the highest in‘Zhengdan 958’,but the lowest in‘Zhuyu 309’;(3)The pretreatment with ABA,F,I and P,all slightly affected the increase of six sHSPs genes expressions,but significantly affected the increase of sHSP26protein expression by heat stress and the combination of drought and heat stress.Our results showed that there was great difference of six sHSPs expression among maize varieties with different endurance.ABA and H2 O2 slightly improve these sHSPs genes expressions,but significantly improve sHSP26 protein expression under the combination of drought and heat stress.These results lay a foundation for further investigating the mechanisms of plants tolerance to combination stress.更多还原