DETERMINATION OF RESISTANCE OF F1 COTTON HYBRIDS BY INOCULATION WITH DIFFERENT VIRULENT ISOLATES OF THE VERTICILLIUM DАHLIAE KLEBHAN
Аbboskhon Маrupov1, Robert Kim2, Rahmatov Asror1, Мichael Кim2
1 - Uzbek Scientific–Research Institute of Crop Protection, the Republic of Uzbekistan, Таshkent province, Кibray district, 4 Bobur str. 2 - Institute of Cotton Seed Breeding and Seed Production, 702147, the Republic of Uzbekistan, Таshkent province, Кibray district, Salar, Universitet Str.
Резюме
Verticillium wilt is one the most harmful diseases of cotton and distributed in all cotton growing regions of the world. It is known, that different species, forms and varieties of cotton have different genetic nature of wilt resistance. Degree of plants affection depends upon the phase of plant development, aggressiveness of strains of fungus, conditions for viability of plant-host and parasite, activity of enzymes, which can change depending upon external factors of environment and agricultural technique of cultivation. Academician S.М. Мirakhmedov (1974), while studying the character of the research of wilt resistant with ecologically distant hybrids of cotton, obtained from crossing of original wild form G.hirsutum ssp. mexicanum with susceptible, medium resistant and resistant varieties of that species, marks the uniformity on resistance to wilt in F1, and in F2 cleavage, close to theoretically expected monogenic correlation 3:1, i.е. three parts resistant and one susceptible. Cimilar correlation on resistance to wilt had been obtained by S. Wilhelm (1974). F.V. Voytenok (1971), while studying inheritance of wilt resistance with intervarietal crossings was observing interim resistance to wilt with F1 and incomplete dominance of susceptibility in F2, in the correlation 1:78, and with ecologically distant hybridization the dominance of resistance in F1 and complex cleavage in F2 in the correlation 263:1. According the opinion of N.G. Simongulyan (1971) resistance to verticillum wilt is controlled by several additionally acting genes. Together with that, the author indicates that polymorphism of the sign is not high, as the genes controlling high-polymeric signs are inherited coherently. About polygenic inheritance of wilt resistance with distant intra- and interspecific hybridization of cotton is reported in the works of S.Y. Кrayevoy and А.E. Egamberdiyev (1975), R.G.Кim (1985) and the others. From the view point of academician S.S. Sadykov (1972), wilt resistance of cotton is defined by the action of two and more dominant genes (R1, R2). Academician А.А.Аbdullayev (1974) thinks that resistance of cotton to wilt is characterized by allel interaction of complimentary genes and genes-modificators. R.G.Кim (1977, 1985); R.G. Kim, A.Marupov (2004); A.Marupov, R Kim (2005, 2007) writes, that wilt resistance is defined by genetic nature of varieties resistance and forms of cotton, and that it has field or horizontal, tolerant and vertical resistance. Thus, with the objectives for creation of wilt resistant varieties of cotton to more virulent races, strains and isolates of the fungus Verticillium dahliaе Klebhan it is necessary to:- study genotypic resistance of varieties and lines of cotton to more virulent isolates of different geographic populations of the fungus V. dahliae obtained from different varieties;- study the inheritance of wilt resistance with hybrids of the first generation to various isolates of the fungus V.dahliae with inoculation of plant – host by monosporous isolates of pathogen.
