| Tomato(Solanum lycopersicum L.)is not only an important vegetable,but also a significant model plant.Planting tomato is a main source of income for some farmers in China,which plays a more and more important role in economy and rural development.Tomato is sensitive to low-temperature,chilling injury cause huge financial losses to tomato industry in China.At present,breeding cold tolerance tomato varieties is an important approach to solve tomato chilling injury.The traditional breeding methods have long production cycle,heavy workload,lack of resources and other shortcomings.It is difficult to use conventional breeding methods to cultivate cold resistant varieties,and transgenic technology provides a good way for breeding cold resistant varieties.Cultivation of transgenic technology of cold resistance materials have advantages of short test cycle and low cost,but the cold resistance plants are composed of a plurality of minor genes controlling complex traits,one or two cold transfered resistance genes couldn’t significantly improve the cold resistance of plants,which has some limitations.Therefore,multivalent gene was transformed into tomato in this study,by analyzing the effect on cold resistance of transgenic tomato plants.The main findings are as follows:1.The integration of AtCBF1 four transgenic tomato and wild type tomato 12 strains in low temperature of 4℃ after 7 days of treatment,2℃ treatment for 14 days,observing the symptoms of tomato plants under low temperature of 4℃ and chilling injury for 7 days.The leaves of four transgenic tomato plants appeared symptoms of prolapse and dehydration,wild type tomato appeared wilting symptoms of dehydration,and some even appeared the main stem lodging,but there was no chilling to death,under the low temperature of 2℃ for 7 days,the wild type tomato plants have been cold to death,four transgenic tomato plants appeared obvious withered and dehydration symptoms,but no chilling to death,under the treatment of 2℃ for 14 days,four transgenic tomato plants appeared serious withered branches and leaves,and the main stem did not lodging.After that,put these tomato plants in 25℃ light incubator for recovery treatment,After 7 days recovery,found that wild type tomato plants were still dead,and four transgenic tomato wilt in branches and leaves returned to normal.After 14 days of recovery,four transgenic tomato plants grow new leaves.These results showed that the expression of exogenous gene quadrivalent enhance cold resistance of tomato.2.The expression of four exogenous genes in tomato and endogenous genes by qRT-PCR were measured.The results verify the tetravalent foreign genes were expressed in transgenic tomato,and the expression of 6h reached the highest value.AtCBF1-2 increased about 12 times,AtCBF3 increased about 30 times;AtICE1increased by about 2 times,tomato endogenous gene Sl Ci7,Sl Ci7,SlDEHL and Sl CAT1 expression also reached the highest value at 6 h,increased about 10 times.3.Under 4℃ treatment for 5 days,the four transgenic tomato and wild type tomato were determined by physiological and biochemical indexes related to cold resistance.The results showed that the transgenic tomato tetravalent relative ion leakage,MDA content were lower than the wild type tomato;and the proline content of four transgenic tomato and antioxidant enzymes(CAT,POD and SOD)activity was higher than the wild type tomato.4.By PCR amplification,3 pure and lines were detected in AtHOS10 transgenic tomato(T2).5.The integration of AtHOS10 eleven transgenic tomato and wild type tomato 12 strain at a low temperature of 4℃ for 7 days treatment,then 2℃ treatment for 14 days,observe the symptoms of these plants under 4℃and chilling injury for 7 days treatment,The leaves of eleven transgenic tomato plants appeared symptoms of prolapse and dehydration,wild type tomato plants appeared obvious wilting symptoms of dehydration,some even appeared the main stem lodging,but there was no chilling to death,under low temperature of 2℃ for 7 days,the wild type of tomato plants have been cold to death,eleven transgenic tomato appeared obvious withered and dehydration symptoms,but no chilling to death,under the treatment of 2℃ for 14 days eleven transgenic tomato plants appeared serious wilting foliage but not dead.Later,put the tomato plants at 25℃ light incubator recovery treatment,in 7 days recovery,found that wild type tomato is dead,and the eleven transgenic tomato plants to send out the main stem bud in.At 14 days,the growth of new shoots of the transgenictomato with the price of eleven increased.These results indicated that the expression of the exogenous gene of eleven increased the cold resistance of tomato.6.The expression of eleven exogenous genes in tomato and endogenous genes by qRT-PCR were measured.The results showed that the eleven price of foreign genes were expressed in transgenic tomato,and the expression reached the highest value at6 h,AtCBF1-3 and At COR15 A increased about 20 times,AtICE1 increased about 10 times,At COR47,AtLTI145 and AtRD29 A increased about 5 times;At CBR15 B,AtHOS10 and AtZAT12 increased about 2 times,tomato endogenous gene SlCi7,the relative expression of SlDEHL also reached the highest value at 6h,and were increased by about 5,3 and 10 times.7.Under 4℃ treatment for 5 days,the price of eleven transgenic tomato and wild type tomato were determined by physiological and biochemical indexes related to cold resistance.The results showed that the relative price of eleven transgenic tomato ion leakage and MDA content were lower than the wild type tomato,and the proline content of eleven transgenic tomato and antioxidant enzymes(CAT,POD and SOD)were higher than that of wild type tomato.This study laid the foundation for the further study of At CBF1,AtCBF2,AtCBF3,AtICE1,At COR15 A,AtCBR15B,AtCOR47,AtHOS10,AtZAT12,AtLTI145 and the regulation mechanism of AtRD29 A gene,and the cultivation of excellent tomato breeding materials. 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