WATER MANAGEMENT FOR SESAME UNDER DIFFERENT SOWING DATES

The present investigation was conducted at Hawaret El-Maktaa village, El-Fayoum District, Fayoum govemorate, Egypt, during 2010 and 2011 seasons to study the combined effect of sowing dates i.e. 81: May 2nd, S2: May 16th and Sa: May 31st and scheduling irrigation treatments, i.e. irrigation at l1: 0.7 cumulative pan evaporation (C.P.E.), l2: 0.9 and l3:1.1 C.P.E. on seed yield, yield components, seed oil content and some water relations of sesame aop (Shandaweel -3 cv.).The split-plot design with four replications was applied, where sowing dates were allocated to the main plots and the split ones were occupied with irrigation scheduling treatments. The main obtained results were as follows:- Highly significant inaeases in plant height(179.22 180.50 an), capsule number/plant (156.42, 165.70), seed weighUplant (19.88, 20.21 g) and seed yield (612.80, 605.89 kg fed^-1) in 2010 and 2011 seasons, respectively, resulted from planting on 2nd May and irrigation at 1.1 C.P.E. interaction. The inaeases in1000-seed weight were not significant in the two seasons, while seed oil content % exhibited similar trend in the first season only. Seasonal consumptive use (ETc) averaged 51.05 and 49.83 an in 2010 and 2011 seasons, respectively. Planting sesame on May 2nd and irrigation at 1.1 C.P.E. gave the highest ETc values i.e. 55.35 and 54.46 an in the two successive seasons. Nevertheless, the lowest ETc values i.e. 47.37 and 45.72 an were detected from planting on MaY 31st and irrigation at 0.7 C.P.E. in both seasons, respectively. The crop coefficient (Kc) average, under interaction of 191 sowing date and irrigation at 1.1 C.P.E., were 0.45, 0.55, 0.85 and 0.64 for May, June, July and August, respectively. The highest water use efficiency values i.e. 0.264 and 0.265 kg seedsm^-3 consumed water were obtained from planting on May 2nd and irrigation at 1.1 C.P.E. interaction in 2010 and 2011 seasons. respectively. However, it is advisable to inigate the early planted sesame aop according to 0.9 CPE treatment to obtain acceptable figure for water use efficiency and to save irrigation water as well.