Estimates of genetic parameters for lint quality in upland cotton (Gossypium hirsutum).

In a half diallel set of crosses involving twelve AH (67) parents and in a full diallel set with nine Albar 51 lines the genetic control of three characters of fibre quality, namely effective length, fibre bundle strength and micronaire value could largely be accounted for by an additive (parent + parent) model. Nevertheless, there were non-additive effects that could be attributed to particular parents. However, for practical plant breeding purposes, it seems that where improvements in lint quality only are being sought, the best breeding method is pedigree line breeding, supported by recurrent selection using crosses of the best lines to produce superior recombinants. Significant interactions between parents and sites for the three lint quality traits indicate that quality tests over a wide range of conditions are advisable at a fairly early stage in any selection programme in Uganda.