Tóm tắt kết quả về nghiên cứu của 36 kiểu gen đó có 8 bậc cha mẹ C92-52, C118A, D99-1, S02-13, TM1, NH042 . | 20 NGHIÊN CỨU KHOA HOC KY THUẬT DI TRUYEN VE THOI GIANSINHJRUONG CHIEU CAO CAY vA nAng suat cUa mOt so GIONG bong THE INHERITANCE OF GROWTH DURATION plant height AND SEEDCOTTON YIELD OF SOME COTTON VARIETIES Phan Thanh Kiềm Ho Tan Quoc Bộ môn Di truyền - Giống Khoa Nông học Đại học Nông Lam ABSTRACT Results on studying of 36 genotypes including 8 parents C92-52 C118A D99-1 S02-13 TM1 NH04-2 VN36P 1354 and their 28 combinations of diallen cross show that growth duration and plant height characteristics were controlled by additive effect of genes but seedcotton yield was controlled by both additive effect and dominance effect. Dominance effect has a major role in controlling cotton yield with an average dominant degree in each locus was . To all studied characteristics there was close relationship between characteristic value and general combining ability with correlation coefficient from - . On seedcotton yield high specific combining ability was present at almost combinations. Short growth duration high plant and high yield characteristics were controlled by dominance genes on the other hand long growth duration low plant and low yield were controlled by genes with recessive effect. About seedcotton yield C9252 VN36P have more than 75 dominance allenes C118A S02-13 and TM1 - between 50 and 75 dominance allenes and D99-1 NH04-2 and 1354 - less than 50 to 25 dominance allenes. There are two groups of genes controlling characteristics of growth duration and plant height three groups of genes controlling cotton yield. For cotton breeding we can use 1354 C118A D99-1 as parents for short growth duration C9252 S02-13 for high yield C92-52 S02-13 tM1 for big boll D99-1 S02-13 NH04-2 for high ginning out-turn and C92-52 for long fiber. There are three prospecting combinations as S02-13 NH04-2 C92-52 NH04-2 and C92-52 D99-1 which have high yield and high fiber quality. Key words Additive effect non-additive effect dominance effect general combining ability
