Associations Between Yield, Yield Components, and Fiber Properties in An Exotic Germplasm Derived from Multiple Crosses Between G. hirsutum and G. barbadense.

Broadening genetic base is essential for genetic improvement of lint yield and fiber quality in upland cotton. An exotic germplasm population derived from multiple crosses between Gossypium barbadense L. and Acala 1517 types was obtained from USDA-ARS at Las Cruces, NM, USA.  This germplasm was designated as JC for the originator, John Cotton.  Two hundred JC lines and five check cultivars were planted at two locations in 2006 and 2007 with two replicates at each location.  Genotypic correlations and their standard errors were estimated by Multivariate Restricted Maximum Likelihood analysis.  Significant genotypic variation for yield and fiber quality was identified.  Interactions between genotype and environment for yield and fiber quality were small relative to the genotypic effects.  Wide ranges of yield, yield components, and fiber properties were identified in JC germplasm.  Lint yield was negatively associated with fiber quality.  Lint per seed was favorably correlated with lint percent, elongation, span lengths, and fineness.  Fiber strength was favorably correlated with 50% span length (r=0.68, P=0.001), 2.5% span length (r=0.15, P=0.05), short fiber content (r=-0.62, P=0.001), and fineness (r=-0.38, P=0.001).  These results indicate that JC germplasm is a useful genetic resource for genetic improvement of lint yield and fiber quality.