Genetic Diversity in Elite Cotton Germplasm Lines Using Field Performance and Rapd Markers

The field experiments of the plant materials used in this investigation was carried out in Egypt during (2002-2005) while, 21 cotton genotypes were subjected to RAPD analysis using 53 UBC 10-mer RAPD primers in (2006) in Lab of Cotton Genetics and Breeding (Department of Agronomy and Horticulture) New Mexico State University, USA. Twenty three primers showed good amplification of cotton genome DNA. A total of 113 scorable bands were detected, among which 96 bands (84.95%) were polymorphic. A dendrogram constructed from the RAPD data classified the 21 cotton genotypes into four major clusters. L was alone in a separate 1 group (A) as the most divergent genotype, followed by L in the second group (B).The third cluster © included 15 13 genotypes and was divided into five sub-clusters, the fourth one (D) included 6 genotypes and divided into three sub-clusters. Results from field experiments revealed large variability for yield and its components between tested genotypes. High broad sense heritability estimates were detected for all traits studied. The cluster analysis based on Euclidean distance using yield characters grouped the 21 cotton genotypes into two main groups at 20 Euclidean distances. Cluster “A” and “B” composed of eleven and ten genotypes, respectively. Highest seed cotton yield per plant and its components was recorded in the three outstanding lines L , L and L . These lines were grouped in the same sub-sub group (B11) based on yield characters (more 10 16 18 closely related) however, based on RAPD analysis, the three lines were classified into different sub-clusters (more genetically distant). This experiment demonstrated that simultaneously RAPD analysis and yield evaluation are useful for characterizing genetic diversity and defining relationships between cotton germplasm lines.