Abstract:
Weed management trials in sunflower were conducted at the National Semi Arid Resources Research Institute (NaSARRI) in 2010, 2011 and 2012. Hand weeding started at 15, 30 and 45 days after planting (dap) and the weeding frequencies were once, twice or thrice. A herbicide called Select of the cloheaxanedione family and with clethodim as the active ingredient was also applied to some plots at 100 mls/15 litres of water once at 15 dap, and twice at 15 and 30 dap. Numbers of weed species and their counts were taken regularly before and one week after treatment applications. Data was recorded on sunflower growth parameters such as height, stem and head diameters. Sunflower was harvested from the four middle rows, threshed, dried winnowed, weighed and yields calculated. Costs involved in the various weed management treatments were recorded and weed control margins calculated.