Tolerance to Low Temperature of Transgenic Aloe Plants with TaDREB Gene from Wheat / 中国生物工程杂志

ABSTRACT

Plant expression cassette for TaDREB from wheat was constructed into plasmid pBIR1.Aloe stems were used as explants for the transformation mediated by Agrobaterium.Infected tissues were selected using G418 to generate transformants.In total,58 resistant plantlets to the antibiotics were obtained from the infected explants.The designed primers according to the selective gene npt II and the target gene TaDREB were used to analyze all of the G418 resistant plantlets.PCR results demonstrated that TaDREB were successful transferred into aloe genomic with the transformation efficiency of 0.5%.The transgenic aloe plants were treated under 4℃ for two weeks and then at-20℃ for 30min.The treatment showed that the leaves of negative plants appeared severe evidence of freeze injury with brown,withered and translucent,while the positive plants appeared good growing condition.The activities of enzymes such as peroxidase(POD)and superoxide dismutase(SOD)of transgenic plants which were stressed for 14 days under low temperature were analyzed.The results indicated that the trend of SOD and POD activities in transgenic plants was down-up-up-up,and that in non-transgenic plants was down-up-down-down.The average value of relative electrical conductivity in the positive plants was 0.456 which was lower than 0.685 in the negative plants.It is supposed that transformation of the kind of gene could improve the resistant ability of aloe to low temperature.