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.