Establishment Of Drought-resistance Evaluation System And Safety Evaluation Studies Of Transgenic Cotton

Drought is one of the major natural disasters in our country,Xinjiang belongs to arid desert area,dry climate;At the same time,Xinjiang is one of the largest cotton production bases in China,And Cotton is a water-consuming crop,The agricultural water crisis is becoming more and more prominent,It is particularly important to cultivate drought resistant transgenic cotton,The effects of drought on cotton can be alleviated to a large extent.The safety problem caused by the resistance of drought-resistant transgenic cotton is the precondition of its application in production and popularization.The 11 transgenic cotton strains obtained by the pollen tube pathway in laboratories and their 3 parental receptor varieties were materials,drip irrigation under plastic film,A total of 5 different irrigation quantities treatment: No irrigation(NI),Low-volume irrigation(LI),Medium-volume irrigation(MI),High-volume irrigation(HI),Normal irrigation(CK),of which the normal irrigation is slightly above the average value of Shihezi cotton area.The agronomic,physiological,photosynthetic and fluorescence of cotton were determined.In order to study the response of transgenic cotton to moisture and the drought resistance evaluation system of transgenic cotton was used to evaluate the drought resistance and survival competitiveness.And the soil physical and chemical properties and microbial community diversity of transgenic cotton and parent cotton were continuously analyzed to reveal the effect of transgenic cotton on soil microbial diversity.And provide the theoretical basis and technical support for guiding the water management and environmental safety of transgenic cotton in the field.The main findings are as follows:1.Using non-irrigation(NI)and normal irrigation(CK)conditions.Principal Component Analysis(PCA),Fuzzy Clustering Analysis(FCA),subordinate function combined weighted average method(D value)and drought resistance index method were used to evaluate the drought tolerance of 11 cotton lines and 3 parent receptors based on their performance under the conditions of irrigation in growing period and water limited cultivation.The results showed that 5 principal components could present 92.825% information of the raw data of the traits related to drought tolerance of cotton.The 11 lines of transgenic cotton used in this study could be divided into 5clusters by Fuzzy Clustering based on their Drought-tolerance Value(DV),which could reflect the drought characteristics and drought resistance of those lines.It was proved that the introduction of exogenous resistance gene increased the drought resistance,and the survival competitiveness of the parental receptor was significantly improved.2.The responses of agronomic character,boll formation,leaf photosynthetic characteristics,and yield were studied with different transgenic cotton lines(24C-1,25C-1)under five different irrigation treatment: no Irrigation(NI),low volume irrigation(LI),middle volume irrigation(MI),high volume irrigation(HI),normal irrigation(CK).The results show that with the increase of irrigation resulted in a progressive increase in Number of buds and bolls,net photosynthetic rate(Pn),lightuse efficiency(LUE),maximum photosynthesis efficiency of PS II(Fv/Fm),actual photosynthesis efficiency of PS II in light(?PS II),and photochemical quenching(qP).However,it led to an decrease in the limiting value of stomata(Ls),water use efficiency(WUE),and non-photochemical quenching(NPQ).the average Pn increased by 31.4% ? 46.2% ? 64.5% and 73.3%,respectively,whereas lint yield increased by 17.5%?31.9%?57.8% and 60.0%,No significant difference between HI and CK.3.25C-1 and its corresponding parental receptors TH2 cotton rhizosphere soil were collected for the determination of soil physical and chemical properties and crop yield in three consecutive planting seasons,And the microbial diversity of soil microbes was determined in the third year.To study the dynamic relationship between crop,soil and soil microbes.The results showed that there was no significant difference in PH value,total nitrogen,available phosphorus and available potassium in transgenic and its parental receptors during the three years,and there was a difference in the soil organic matter(OM)in 2014/2015,2014/2016 and abundance of Arthrobacter_oxydans and Lysobacter_soli.The results showed that there was no significant difference in soil physical and chemical properties between transgenic and its parental receptors during continuous cropping season,while soil organic matter was significantly different during the year.Therefore,The cotton straw returning to the field could lead to drought resistance genotype and parental receptor rhizosphere the root cause of ecological differences.