ABSTRACT
Fourty-one strains of cotton descending from 10 Egyptian varietal crosses were included in Preliminary Trial A, and 24 strains descending from 9 crosses were included in Trial B in 1993. Those strains were compared with the standard variety Giza 80. Trial A was raised in Middle Egypt in Sids, whereas Trials B were held at five different locations in Middle and Upper Egypt. The results obtained from Trial A and Trials B showed that only 3 crosses are promising according to lint cotton yield combined with desirable fiber properties. These crosses are: Giza 83 (G. 75 x 5844A), radiated Ashmouni 302 x G. 83 and G. 83 x G. 80. The high heritability value in Trials B in 5 locations indicate that the studied crosses were affected by the environment. The highly significant interaction suggested that more testing for another few years is necessary until a satisfactory genetic stability is achieved. Genetic gains at 5% intensity of selection were 16.14 and 13.97 for lint yield in Trials A and B, respectively. These values were also linked with moderate heritabilities indicating that improvement of lint yield is possible through selection. Genetic coefficient was high for lint yield in Trial A (9.40), while this value was intermediate (7.48) in Trials B over the combined analysis for environments.
|