Evaluating And Utilizing The Freezing Tolerance Of Acaulia

Potato,as one of the major food crops around the world,plays a vital role in Chinese agricultural industry.However,the low temperature and frost can be a big threat during its growing,and there is no cold-resistant germplasm in potato cultivar.Therefore,creating the freezing tolerance germplasm in potato has been very important.Acaulia Juzepczuk,a wild potato series containing three species,is considered as the best freezing tolerance germplasm.Thus it can provide solid supporting for the healthy and stable development of potato industry by strengthening the evaluation and utilization of the Acaulia Juzepczuk wild species' capacity to freezing tolerance.In this study,63 clones from Acaulia Juzepczuk have been used to systematically evaluate freezing tolerance of Acaulia Juzepczuk species and new freezing-tolerance germplasms which possess some Acaulia Juzepczuk gene have been created by cross-fertilized.The main results are as follows:1.By evaluating the cold-resistance of 63 clones from S.acl?S.alb?S.×aem and more than 2000 self-pollinated progenies from several S.acl clones,it can be concluded that all these 63 clones have strong ability of freezing tolerance(FT),and partial clones of S.alb?S.×aem have strong acclimation capacity(ACC),which can even bear the low temperature as 2 ?.S.acl's over 2000 self-pollinated progenies have shown great cold-resistant and there is no distinct segregation among the progenies.When it comes to the results of botanical characters,there is a high similarity in growth vigor and tuberization about the three potato wild species.Meanwhile,the research has found that the growth vigor and tuberization of clones from S.alb(6X)are slightly stronger than the other two species(4x).2.A freezing tolerant line AEM669-4(4x)and a sensitive line J101K27(5x)were hybridized as parents(AEM669-4×J101K27)to create the new germplasms(FT033)with freezing tolerance.All of the clones from hybrid population are triploid,and the cold-resistance of the hybrid population is between the two parents,but as a whole,it biased toward cold-resistant parent AEM669-4,and some clones have acclimation capacity(ACC)even to 2 ?.Also,the agronomic traits,such as growth vigor and tuberization,of the hybrid population are between the two parents,and they biased toward J101K27 in general.The results indicate that most of clones from hybridpopulation are freezing tolerant and agronomic traits preferred for breeding goals,thus they could be used as middle materials for potato breeding with cold-resistant trait.