EXPLOITATION OF HETEROTIC EFFECTS IN F1 1 HYBRIDS FOR PROMOTING EARLINESS, YIELD COMPONENTS, AND FIBER QUALITY OF UPLAND COTTON ( GOSSYPIUM HIRSUTUM L.) GENOTYPES

Cotton is an often-pollinated crop and can be manipulated by exploiting heterosis achieved from different crosses among cotton genotypes for boosting lint yield and quality traits. The development of a new short-duration varieties having high yield and superior fiber quality are direly needed for sustainable supplies of lint to local textile industry. For this purpose, 12 parents and their half-diallel hybrids were sown at Hama Center for Scientific Agricultural Research, Syria during the summer of 2019 and 2020 to study the heterotic effects for the traits (earliness, yield, and fiber quality). The analysis of variance (mean squares) showed highly significant differences of the genetic variability among genotypes for all characteristics under investigation. Likewise, estimation of relative heterosis (MP), heterobeltiosis (HP), and standard heterosis (SC) showed significant superiority of some hybrids for all characteristics. The highest number of hybrids with significant heterosis was observed for earliness index (E %) and fiber elongation (FE), while the lowest was observed for fiber fineness (FF). Hybrids, Fantum x Coker 139, NIAB 414 x Deir ELzour 22, Coker 139 x NIAB 414, and Coker 139 x Raqqa 5 exhibited desirable heterosis for most of the traits under study. Thus, these cross combinations may become potent candidates for future hybridization programs in order to exploit heterosis for boosting the seed cotton yield (SCY), earliness and fiber quality traits by developing new varieties.