Assessment of Genetic Diversity in some Egyptian Cotton Varieties Based on Molecular and Technological Characteristics

Abstract

Cotton is an economic plant of world importance. It's the world's leading textile fiber crop. The lack of genetic diversity is implicated in the successful breeding program depends on the slowing of progress in developing new cotton cultivars complete knowledge and understanding of the genetic with improved yield and quality potential, as well as diversity within and among genetic resources of the stress resistance. The present study was carried out at the Agricultural Botany Department and Department of Plant production Faculty of Agriculture, Saba Basha, Alexandria University, Egypt. Five commercial varieties representing the two categories of Egyptian cotton were used, namely: Giza 92 and Giza 88 as extra-long staple length and Giza 86, Giza 95 and Giza 90 as long staple length. These studies were conducted during 2015 up to 2018. Fiber properties of the five cotton varieties under study were determined by the High-Volume Instrument (H.V.I.). Ten RAPD primer, were initially screened to determine the suitability of each primer for the study. Isozyme data proved 100% genetic similarity between the extra-long staple cotton, in the other hand 100% between the long staple cotton varieties, although, the cluster was divided by 62%. The results indicated that in all studied cotton varieties, 224 (71%) of the 312 fragments were polymorphic and 88 (29%) were monomorphic. From these data, we can provide that there are high genetic variations between the two-cotton type in Egypt and these found could be useful in breeding program in the future. Cotton productivity and the future of cotton breeding efforts tightly depend on the level of the genetic diversity of cotton gene pools and its effective exploitation in cotton breeding programs. Elucidating the details of genetic diversity is also very important to determine timeframe of cotton agronomy, develop a strategy for genetic gains in breeding, and conserve existing gene pools of cotton.