Alkali Tolerance Identification Of Transgenic T?DREB3? Soybean Lines

Soil salinization is a worldwide problem in recent years.Planting common soybean varieties on this soil has resulted in weak resistance,low yield and poor quality.The objective of this research is to improve the alkali resistance in soybean.Firstly,stress treatments of common soybean varieties(Dongnong50)with different concentrations of NaHCO3 and Na2CO3 alkali solutions were carried out at budding,seedling and flowering stages,and the critical concentration range of Dongnong50 soybean in each stage was screened out.Then,the alkali tolerance of Dongnong50 soybean(non-transgenic)and T?DREB3? transgenic soybeans at different stages was analyzed according to the critical concentration range screened from the above stages.The main research work was as follows:(1)In the bud stage,seedling stage and flowering stage,the suitable alkali concentration range was screened by determining physiological indexes of cultivated soybean Dongnong50 under different concentration of alkali stress.According to the range of alkali concentration screened at budding stage,T?DREB3? transgenic soybean and Dongnong50 were cultured in a dish with different concentrations of Na HCO3 and Na2CO3 to determine the germination rate,germination potential,main root length and lateral root number.The results showed that the germination potential,germination rate,main root length and lateral root number decreased significantly with the increase of Na HCO3 and Na2CO3 concentration(P<0.05),and the transgenic soybean was significantly higher than Dongnong50.Among them,the indices of transgenic strain 564-1-1 was the most different from those of the control,showing the strongest alkali tolerance.The results showed that the alkali tolerance of soybean was significantly improved by introducing the alkali tolerant gene T?DREB3?.(2)According to the alkali concentration range screened from above seedling and flowering stages,Dongnong50 soybean and transgenic soybean were treated with Na HCO3 and Na2CO3 stress by mixing soil with vermiculite(1:3).The plant height,leaf area,chlorophyll content,fresh weight,dry weight,relative conductivity,malondialdehyde,soluble protein content,SOD and Other physiological indicators of alkali tolerance of Dongnong50 and transgenic soybeans were determined.The results showed that plant height,leaf area,fresh weight,dry weight,chlorophyll content and SOD activity showed a trend of initially unchanged and then significantly decreased with the increase of alkali concentration,The indices of transgenic strains were higher than those of control strains.while relative conductivity,malondialdehyde and soluble protein content showeda trend of first unchanged and then significantly increased,The indices of transgenic strains were lower than those of control strains.Among them,the indices of transgenic strain 564-1-1 was the most different from those of the control,showing the strongest alkali tolerance.The results showed that the alkali tolerance of transgenic soybean was significantly higher than that of non-transgenic soybean when the gene T?DREB3? was transferred.(3)Dongnong50 and transgenic soybeans in the whole growth period were planted in alkaline soil with p H 8.9 to compare the difference of them.It was found that the persecution degree of Dongnong50 in seedling and flowering stage was significantly higher than that of transgenic soybean.The plant height,chlorophyll content and dry and fresh weight of transgenic soybean were significantly lower than those of transgenic soybeans,while the relative conductivity was significantly higher than that of transgenic soybean.At adult stage,the plant height,number of main stem nodes,number of branches,number of pods per plant,number of grains,number of 100 grains,weight of 100 grains and theoretical yield of transgenic soybean were significantly higher than those of Dongnong50 soybeans.Among them,the indices of transgenic strain 564-1-1 was the most different from those of the control,showing the strongest alkali tolerance.The results showed that the alkali-tolerant gene could improve and utilize alkaline soil,improve soybean resistance and increase soybean yield.