Effect of Different Irrigation Water Quantities and Cultivars on Growth and Yield of Sesame (Sesamun Indicuml)

Abstract

A field experiment was conducted in the Demonstration Farm of the Faulty of Agriculture, University of Khartoum at Shambat, for two successive seasons (2001/2002 - 2002/2003). The aim of the study was to investigate the effect of different irrigation water quantities (750, 650, 550, 450, and 350 mm) and cultivars (Khidir and Promo) on growth and yield of sesame. The treatments were arranged in a spit plot design. Expansive and reproductive growth attributes, root growth attributes, crop phenoloy, yield and yield components, seed index, harvest index, seed oil content, protein content and seed moisture content were examined. Soil moisture content, leaf turgidity, actual evapotranspiration, estimated evapotranspiration using Penman-Monteith and modified Penman equations and water use efficiency (W.U.E) were calculated. Crop coefficients (factors) were quantified by comparing the actual evapotranspiration measured in the field with modified Penman formula, Penman-Monteith method and pan evaporation. The highest irrigation water quantity (750 mm) resulted in a significant increase in the expansive and reproductive growth structures produced and induced significant increase in seed yield and yield components. However, th highest values of harvest index (H.I) and water use efficiency (W.U.E) were obtained under irrigation water (650mm) The lesser irrigation water quantity (350 mm) resulted in a greater reduction in the expansive and reproductive growth attributes, yield and yield components and H.I. However the lesser value of W.U.E was obtained under treatment (450 mm). The increase in irrigation water quantities resulted in an increase in seed oil content associated with decrease in seed protein content. Soil moisture content in top layers and leaf turgidity were greater under the highest irrigation water quantity and decreased as irrigation water quantity decreased. Evaporation values, estimated with pan, were higher than those with modified Penman formula and Penman-Monteith equation There was a tendency of decreasing values of crop coefficients with decreased irrigation water quantities and with pan evaporation resulting in greater values than with modified Penman and Penman-Monteith methods. The results showed that there was variation among cultivars in the expansive and reproductive growth structures produced. The cultivars revealed insignificant effects on seed yield per plant, final seed yield (t/ha) and H.I. Promo reached the 50% flowering and physiological maturity earlier than Khidir. Khidir had a higher seed oil content and lesser seed protein compared to Promo