EFFECT OF SOWING DATE AND PIX (MEPIQUATE CHLORIDE) TREATMENT ON GROWTH, EARLINESS AND YIELD OF GIZA 87 COTTON CULTIVAR (GOSSYPIUM BARBADENSE L.)

Two field experiments were carried out at Sakha Agric. Res. Sta­tion during 1996 and 1997 seasons to study the effect of sowing dates (early: the last week of March and late:the last week of April) and Pix treatment [untreated (control); 2 sprays of 250 miffed; 2sprays of 500 ml/fed; 4 sprays of 250 ml/fed and 4 sprays of 500 mitred.] on growth characters, earliness measurements and seed cotton yield and its com­ponents of Giza 87 cotton cultivar. Results indicated that early sowing significantly increased plant height, number of sympodia, total dry matter, number of main stem in­ternodes, percentage of boll retention, earliness%, number of open bolls, boll weight, lint %, seed index, percentage of plant losses at harvest/ fed. and seed cotton yield (Kentar/fed.), while it decreased main stem internodal length. Sowing date did not affect number of monopodia, number of aborted sites, nodal position of the 1st sympodium and num­ber of unopen bolls/plant. Spraying Pix 2 or 4 times with 250 or 500 cm/fed. increased number of sympodia, total dry matter, number of main-stem internodes, percentage of boll retention, earliness%; number of open bolls, boll weight, lint%, seed index and seed cotton yield while it decreased plant height; main-stem internodal length and number of aborted sites/plant, compared with untreated plants. Pix application did not exert any signifi­cant effect on number of monopodia, nodal position of the 1st sympodi­um; number of unopen bolls and percentage of plant losses at harvest/ fed. The interaction between sowing date and Pix treatment had no sig­nificant effect on any character in this study. Best results were obtained when cotton plants were sown early in the season (through March) and sprayed with Pix at squaring and bud in­itiation.