PERFORMANCE OF SOME GRAIN SORGHUM (Sorghum bicolor l. Moench) GENOTYPES UNDER DIFFERENT SOWING DATES IN EGYPT

Two field experiments were conducted in 2010 and 2011 seasons to investigate the influence of sowing date (April 7, April 27, May 17, June 6, and 26) on growth and yields of some sorghum genotypes (Shandaweel-1 hybrid, Shandaweel-305 hybrid, Shandaweel-306 hybrid and Dorado cultivar) grown in clay loamy soil at Giza Governorate, Egypt. Results obtained showed that growth and yield attributes of grain sorghum were significantly affected by sowing date and genotypes in both seasons.
                Delaying sowing from April to late May or June resulted in increasing growth attributes (plant height, number of green leaves, leaf area and total dry weight/plant). Late sowing in June accelerated plant maturity. Sandaweel-305 hybrid plants were the tallest and the earliest in maturity compared to the other genotypes. Sowing Shandaweel-306 hybrid at June produced the highest yield and yield components compared to the other genotypes planted at earlier sowings (April and May). The results also showed that grain yield was positively correlated with panicle weight (r = 0.52), kernel weight panicle^-1 (r = 0.43), leaf area (r = 0.50) leaf area index (r = 53) and total dry weight (r = 0.43) suggesting that these parameters could be used to estimate sorghum grain yield.