Assessment of Weed Control Methods and Their Effect on Sorghum Yield in Zamfara State

This study assesses different weed control methods and their comparative effect on sorghum grain yield in Zamfara State, North West Nigeria. Weed competition is one of the most significant yield-reducing factors in sorghum production, particularly during the critical first six weeks of crop establishment. In Zamfara State, where sorghum is a staple food crop, weed control is predominantly conducted through labour-intensive hand weeding that is becoming increasingly costly and difficult due to rural labour shortages. This study establishes a field experiment in Gusau, Anka, and Kaura-Namoda local government areas, comparing five weed control treatments: no weeding control, two hand weedings, pre-emergence herbicide (atrazine), post-emergence herbicide (2,4-D), and inter-row mechanical cultivation using a power tiller-mounted cultivator. Weed density, weed dry weight, and sorghum grain yield are measured at 4, 8, and 12 weeks after planting and at harvest. Findings reveal that two hand weedings produce the highest grain yield of 3.2 tonnes per hectare, followed closely by pre-emergence herbicide at 3.0 tonnes per hectare. Mechanical inter-row cultivation achieves 2.8 tonnes per hectare and shows significant labour cost savings compared to hand weeding. No-weeding control produces the lowest yield of 1.4 tonnes per hectare. The study concludes that mechanical cultivation offers the best balance of yield and labour cost for Zamfara State sorghum farmers. It recommends power tiller adoption with cultivator attachments.

Keywords: weed control, sorghum yield, Zamfara State, mechanical cultivation, herbicide.