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enetic divergence is the basis for any crop improvement programme. The knowledge of genetic variation existing in the germplasm is an important and essential aspect for initiating any crop breeding programme because hybrids between lines of diverse origin generally display a greater heterosis than those between closely related parents.Classificatory techniques are being used to quantify the genetic divergence in a given population of cotton using cluster analysis to select some promising plants (Abd El-Baky 2006; Abd El-Sayyed et al., 2006). As such a quantification of the degree of divergence would be of help in choosing suitable genotypes for on-going cotton breeding programme.Metroglyph analysis is a simple technique used for preliminary grouping of accessions. With the help of this technique, breeders can easily predict genotypes which have high index scores and can fall into different clusters to be crossed giving maximum variability of good combinations of characters. Khan et al. (2007) found that metroglyph analysis and index score were a useful tool to assess genetic variability among cotton population. Likewise, Haidar et al. (2012) used metroglyph analysis to classify thirteen locally developed elite cotton genotypes and two exotic lines (Gossypium hirsutum L.) into six clusters for some qualitative and quantitative characters. (2014) grouped 86 intra-hirsutum lines for 15 yield attributes and quality characters into nine clusters, using Mahalanobis D² statistic to measure the genetic divergence. The inter cluster distances were found to be greater than intra cluster distances, revealing considerable amount of genetic diversity among the studied genotypes. MATERIALS AND METHODSThe present investigation consisted of the selfed seeds of twenty cotton genotypes belonging to Gossypium barbadense L. Origin and pedigree of these genotypes G

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Agronomic and seed chemical characters of cottonseed play a prime role in seedling vigor establishment for cotton plant to obtain the maximum stand and better growth. Nutritional components in the seed play a very important role in early seedling developmental stage to produce healthy plants. The present study was conducted to investigate the genetic variability and relationship among agronomic, chemical components and seedling vigor characters of eight Egyptian cotton varieties (Gossypium barbadense) classified into two categories according to their fiber quality properties (long and extra long staple). The results showed highly significant genotypic variation for all the studied characters, which reflect the genotypic variability between the studied genotypes. Broad sense heritability ranged from moderate to high values for all the studied characters. Genetic divergence (D 2 ) showed highly significant dissimilarity between the two categories of Egyptian cotton varieties, except between the extra long staple category. There was a highly significant and positive association between protein content and seed volume, lint index and seed index, also between oil content and carbohydrate content (0.583). While, seed oil percentage was not correlated with seed properties except lint percentage and a highly significant and negative correlation between seed protein and oil content. Most of the studied characters showed highly significant dissimilarity coefficients between and within these studied characters, which reflect the genetic variation background of these genotypes. Significant positive correlation and dissimilarity coefficients among and within these studied characters suggest that selection may be useful for the enhancement of the correlated characters.