Study On The Inheritance Of Resistance To Fusarium Wilt And The Molecular Marker Selection In Gossypium Barbadense

Gossypium barbadense is a kind of the most important cultivated cotton in the world,As the only island cotton growing areas of our country, Xinjiang province provides unique advantages for development superiority,depending on its favorable natural conditions for the development of island cotton. But for years,the Fusarium wilt in island cotton has not been resolved because of the lack of resistance to Fusarium wilt of island cotton varieties. Conventional breeding methods, through hybridization, backcross in chosing resistable species to Fusarium wlit. But the process has gotton on very slowly because island cotton lacks in high resistable and stable Fusarium wilt resistable species,on the other hand, the hybridize offspring between upland cotton and island cotton was in high separateness and slowly stable,on the last hand,the research on the island cotton resistance identification was susceptible by the environment,pathogens and other factors. With the rapid development of the molecular marker technology,it offered a new way to cultivate resistable species using modern molecular breeding technology combined with conventional methods.This experiment studied the inheritance of resistance to Fusarium wilt and screen the SSR molecular markers in Gossypium barbadense by taking the high production,quality and susceptible G.barbadense xinhai21 and the resistant Gbarbadense HK237 as parents.The objectives were to search themolecular markers linked with the resistance gene.The main results were as follows:1.Analysis of the amount of resistible and susceptible individuals indicated that they shew evident double peak distribution.The result indicated that among the F1,BC1 and F2 population,the resistant individuals:susceptible individuals accorded with 1:0,1:1,3:1 and it accorded with xe2 text. According to the result,we found that the resistance to Fusarium wlit of HK237 was qualitatively inherited trait and controlled by a single dominant gene.2.Two thousand three hundred and forty-seven SSR primers were screened using the BSA method. Out of these primers, eight pairs of primer showed polymorphic between parents and resistant,susceptible DNA pools.These primers were NAU114,NAU3119,NAU3240,NAU5411,BNL1169,TMH05,CIR035 and Gh633.The PCR results amplified by the eight SSR primers of these F2 individuals were analyzed by using Mapmaker/Exp(Version3.0b) software,The results indicated that NAU3240 linked with the gene of G.barbadense Fusarium wlit resistance and the genetic distance between them was 19.0cM, The polymorphic markers amplified by NAU114,NAU3119,NAU5411,BNL1169,TMH05,CIR035 and Gh633 did not linked with the resistant gene.3.The application value of NAU3240 was validated by F2 crosses of xinhai21xHK237 and xinhail4xHK237.They all had one hundred individuals.The result indicated that most of the resistant plants had NAU3240 and it can be used in marker-assisted selection and the practice of breeding.