Identification And Phenotypic Analysis Of Transgenic AtABA₂Cottons

Cotton can provide excellent natural fiber, which is an excellent textile material due to its lowcost, large output and good thermal properties. Owing to lack of cotton germplasm resource, lessprocess is made in Cotton traditional breeding. Great progress has been made in biotechnology,such as the introduction of an exogenous gene into the crop genome to inherite and expresssteadily, thus modify organisms. Cotton is a very important economic crops, China is a bigcotton-producing countries. Drought is the most influential factor to the global agriculturalproduction and cause the most serious economic losses.About51percent of China’s total arableland is arid and semi-arid arable land, nearly2.5million hm2of farmlands are affected by thedrought to some degree every year. Traditional irrigation methods are stick-in-the-mud,water-consuming, use-inefficient, thus does not work.Abscisic acid (ABA) is a very important hormone in plants, which play a key role in theregulation of seed development, dormancy, stomatal closure and crop resistance. As is known,three genes AtABA1, AtABA2, AtABA3play a core role in the synthesis of ABA process inArabidopsis. In this paper, we use transgenic technology to improve the capacity to synthesis ABAto improve drought resistance of cotton.Here, AtABA2gene is successfully transduced using Agrobacterium-mediated transformationinto JiHe713, coker201embryogenic callus. AtABA2gene is also successfully transduced intoXinluzao35.36and Zhong mian16by pollen tube pathway. A lot of transgenic plants areobtained through the latter method. After, we screened preliminarily by spraying antibiotics in thefield and PCR method. We culture the positive plants, and then AtABA2is confirmed integratedinto the T4generations by molecu了ar hybridization techniques with single copy. The expressionlevel of AtABA2gene is analyzed after drought stress treatment by RT-PCR in transgenic andnon-transgenic cotton. The result showed that AtABA2is expressed in transgenic cotton in vivo,while non-transgenic modified is not detected in vivo. Their growth condition, water loss rate of the leaves, morphology and density of stomata aswell as lateral root growth conditions are compared with AtABA2transgenic and non-transgeniccotton after drought treatment or not. We found that the growth condition of the transgenic cottonis better and the water loss rate is lower, compared with non-transgenic cotton. However, themorphology and density of stomata and the lateral root growth conditions show little differencebetween the AtABA2transgenic and non-transgenic cotton.Above all, Comprehensive analysis shows that the drought resistance of cotton is improved bythe AtABA2gene.