Association Analysis And Tne Major Gene ERECTA Cloning Of Carbon Isotope Discrimination In Wheat

Wheat is mainly grown in arid and semi-arid areas. The annual loss due to drought stress was equal to all that by the other adversities. To enhance crop drought tolerance and water use efficiency (WUE), and develop water-saving agriculture in particular"biological water economy"has become a worldwide issue. High water use efficiency is the effective way to achieve water saving and yield basis. Many studies have pointed out that the carbon isotope discrimination (â–³) is a comprehensive index of water use and dry matter formation, also an indiret index reflecting the efficiency of crop transpiration. And studies have shown that ERECTA gene can explain 21%~64% variation ofâ–³in Arabidopsis thaliana, which has been identified as the major gene ofâ–³.Our study involves three aspects: First, explored the relationship betweenâ–³and other stomata-related indicators; Second, screened molecular marker ofâ–³with the method of association analysis associated; And then tried to clone the ER gene in wheat. Mainly the following findings:1. It was concluded that the seeds should be more suitable sampling material forâ–³under the climatic conditions in northern China; The period of mid-May (or 20-25 days after filling) was the right time to measure the stomatal relevant indicators due to the abundant rainfall in this period made the good genetic stability of stomatal relevant indicators, and the stomatal conductance and temperature of flag leaf in this period were hopeful to be used as the substitution indexes forâ–³.2. 15 random primers and 25 SSR primers was used to test the 56 wheat genotypes. Then integrated the molecular markers data, Q from STRUCTURE, K from SPAGeDi andâ–³values in the mixed model-MLM of TASSEL software to screen the relative markers ofâ–³.Found four sites significantly associated with two yearsâ–³value of flag leaf: Xgwm131 on 1B, Xwmc524 and Xwmc713 on 5A , Xgwm282 on 7A; And through the analysis ofâ–³and vector species, we found two extreme wheat germplasm materials Changwu 521-7 and the West 35, whitch respectively carriy the strongest additive and reductive allelic variation.3. A 2485bp's cDNA fragment of ER gene was cloned in wheat. There is still a partial sequence of about 632bp from the 5'end needed to be cloned. Sequence analysis based on the sequence of Brachypodium distachyon, indicates that it encodes 771 amino acids, and contains 3 relatively conservative domains of PKc, PLN00113 and Protein kinase. Alignment among homologous sequences from different plant species indicated that the closest relationship of wheat ER gene was with Brachypodium distachyon, followed by rice and sorghum, and the farthest genetic relationship with Physcomitrella patens.