SOURCE AND SINK CAPACITY IN RELATION TO YIELD OF SOME EGYPTIAN COTTON VARIETIES 2- RESPONSE OF COTTON VARIETIES TO DIFFERENT PLANT DISTRIBUTION DENSITIES

Two field experiments were carried out in 2003 and 2005 seasons to investigate the response of photosynthetic and reproductive organs of Giza 70, Giza 85, Giza 88 and Giza 89 colton cultivars to six plant distribution densities, i.e (60 X 15), (60 X 20), (60 X 25), (80 X 15), (80 X 20) and (80 X 25) cm. The experimental design used was split - plot with four replications. Results elucidated that dense distribution exhibited taller plants and lower number vegetative branches with Giza 89 variety, lower number of leaves, dry weight of leaves and also leaves area with Giza 85 variety. Leaf area index (LAI) of dense distribution was greater than that of thin distribution with Giza 89 variety. Number of open bolls and dry weight of bolls per plant of (80 X 25) cm distribution for Giza 89 variety showed greater values than other densities. Moreover, different parts of cotton boll, i.e. seed, lint and loculi of thin planting were heavier than dense ones. However, seed cotton yield of (80 X 15) cm distribution density was greater than other treatments with Giza 89 cultivar.