Most of the time, plants are exposed to diverse environmental stresses, such as high light intensity, cold, salt, heat, drought, and waterlogging . Among these stresses, heat stress is an agricultural problem in many areas of the world. Previously, the APX activity and gene expression of heat-tolerant “ASVEG2” Chinese cabbage was significantly higher than those of heat-sensitive RN720 plants under the heat-stress conditions . Full-length of the BcAPX1 cDNA was 1056 bp,including 753 bp of an open reading frame in the APX gene. In addition, BcAPX2 and BcAPX3 were a type of isoform to BcAPX1 from ASVEG2 under heat induced environment, and were cloned in the current study.
The objective of this study was to transfer the BcAPX1, BcAPX2 and BcAPX3 cDNAs under the control of ubiquitin promoter to Arabidopsis via Agrobacterium tumefaciens strain GV3101. The transformation rate of BcAPX1, BcAPX2 and BcAPX3 in arabidopsis were 1%, 0.6% and 0.6%, respectively. The results from PCR and RT-PCR indicated that the transgenes had been transferred into arabidopsis genomes, and transcribed as well. The results from APX activity assay and Western blot revealed that activity and expression of APX in transgenic line were higher than those of non-transgenic plants under the heat stress. The results of physiological assay and appearance showed that transformants were higher resistance to the heat treatment compared to non-transforment under heat stress.
