Description of inheritance for lint quantity and quality in cotton by factor analysis

The objective of this study was to evaluate the efficiency of factor analysis as one of the multivariate statistical methods into describing the mode of inheritance for lint quantity and quality in cotton. Seeds of six cotton cultivars along with 240 F6 recombinant inbred lines were planted to study in Hashem-Abad agriculture research station, Gorgan, Iran. The results of factor analysis showed that 83% of relevance among the parents was successfully explained by the six first factors. Based on the factor loadings, the three first factors were named "lint and seed production", "vegetative growth" and "lint quality". Biplot of factor scores showed that the highest "lint and seed production" and "vegetative growth" was belonged to cultivar Sahel, and there was no cultivar with high "lint and seed production" and low "vegetative growth". The highest score for factor "lint quality" was belonged to cultivar Number 200; and Sahel was intermediate in this respect. Among the all crosses, there was no lines showing superiority for the both factors "lint and seed production" and "vegetative growth" and most of the studied lines were intermediate for these factors. Among the evaluated F6 lines, the highest score for factor "lint and seed production" belonged to lines that had cultivar Sahel as one ancestor in their pedigree. The high potential of cultivar Sahel and its crosses proved that this cultivar is are still a very profitable pool containing genes controlling quantity and quality of lint in cotton for growing area in the North of Iran, particularly for Golestan province. The validity of parent-offspring relationship and predictability of performance of crosses for "lint quality" implies the concept of combining ability of the used cotton parents for this factor. It concluded that, factors as a linear combination of simple variables could be used as usual variables in quantitative genetics studies.