Critical Period of Weed Interference in Sesame (Sesamum indicum L.) in Dongola Locality, Northern State, Sudan

Abstract

A field experiment was conducted at Altraa village, Sherg Elneel Unit, Dongola Locality, Northern State, Sudan, during two consecutive summer seasons of 2010 and 2011 to determine yield loss in sesame (Sesamum indicum L.) inflicted by weeds and to identify the critical period for weed interference. Sesame, cultivar Promo, was sown on 23 June in both seasons. A set of weeding regimes comprised of 12 treatments was arranged in randomized complete block design, with four replicates. The crop was kept weed-free for the first 2, 4, 6, 8 or 10 weeks after crop sowing and then remained weedy till harvest or kept weedy for the same periods and then remained weed-free till harvest. Weed free and weedy treatments till harvest were included as controls for comparison. Combined analysis of both seasons indicated that unrestricted weed growth significantly reduced sesame seed yield by 53.2% compared to weed free full season treatment. Seed yield decreased as the weed infestation period increased. Number of leaves/plant was significantly reduced by 58.93% under full season weed infestation. The same trend was observed for the first capsule height from the soil surface, plant height, and number of branches/plant. The critical period of weed competition was found to be between 2-6 weeks after crop planting.