以玉米脱落酸(ABA)缺失突变体vp5及其野生型Vp5的叶片为材料,分别采用ABA、碘化钾(H2O2清除剂)、钨酸钠(ABA抑制剂)预先处理,对干旱+高温复合胁迫下玉米叶片小热休克蛋白(sHSPs)基因表达进行研究,以确定H2O2和ABA对干旱+高温复合胁迫诱导的玉米叶片sHSPs基因表达的影响。结果显示:(1)与对照和干旱相比,高温、干旱+高温复合胁迫显著诱导了sHSP16.9、sHSP17.2、sHSP17.4、sHSP17.5、sHSP22和sHSP26等6种sHSPs的表达。(2)H2O2清除剂KI和ABA抑制剂钨酸钠预处理,仅略微抑制高温、干旱+高温复合胁迫诱导的6种sHSPs表达。(3)与未用100μmol/L ABA预处理的vp5相比,100μmol/L ABA预处理仅略微提高了高温、干旱+高温复合胁迫诱导的6种sHSPs的表达水平。研究表明,在干旱+高温复合胁迫条件下H2O2和ABA参与了干旱+高温复合胁迫诱导的玉米叶片sHSPs表达,但并无显著影响,暗示了H2O2和ABA不是干旱+高温复合胁迫诱导sHSPs表达的重要调控因子。
Using maize ABA deletion mutation vp5 and its wild-type Vp5 leaves,pretreatment with H2O2 scavenger KI and ABA inhibitor tungstate(T),as experimental material,sHSPs expression were investigated with RT-PCR to determine the influences of H2O2 and ABA to sHSPs expression induced by the combination of drought and heat stress in maize(Zea mays L.).The results were as follows:(1)Compared with the control and drought,heat stress or the combination of drought and heat stress significantly induced the gene expression of sHSP16.9,sHSP17.2,sHSP17.4,sHSP17.5,sHSP22,and sHSP26.(2)The pretreatment with H2O2 scavenger KI and ABA inhibitor T,only slightly inhibited the genes expression of six sHSPs that induced by heat stress or the combination of drought and heat stress.(3)Compared with vp5 maize plant that without 100 μmol/L ABA pretreatment,the pretreatment only slightly increased the six sHSPs genes expression induced by heat stress or the combination of drought and heat stress.These results indicated that H2O2 and ABA participated in sHSPs expression induced by the combination of drought and heat stress in maize leaves,but the effect was not significant,which suggested that H2O2 and ABA were not important regulatory factors of the six sHSPs induced by the combination of drought and heat stress