Persistence of Pendimethalin in Southern Guinea Savanna, Ogbomoso, Nigeria
Adelasoye, K. A.; Popoola, K. O. K.; Ogunyemi, S. and Awodoyin, R. O.
Journal Title:Journal of Environmental Issues and Agriculture in Developing Countries
Pendimethalin is experimented for persistence using Spectronic 2ID for residue analysis in Ogbomoso, Southern Guinea Savanna soil. Pendimethalin (1.0, 1.5, 2.0 l/ha), hoe weeded and Weedy Check (WC) were the applied treatments.Soil samples were taken for herbicide residue analysis to determine Disappearance Time for 50% (DT50) of the herbicide. The lowest rate, 1.0 l/ha disappeared faster than 1.5l/ha. Up to 75.2 days after application, 75% of the herbicide at the recommended rate of 2.0l/ha had disappeared. The DT50 were 48.3, 57.3 and 37.9 days for 1.0, 1.5 and 2.0 l/ha respectively. There was inadequacy in weed control ability of Pendimethalin due to the loss in quantity of the herbicide from the soil in this zone. Thus, before eight weeks of application more than half of the applied herbicide had disappeared leading to reduced weed control. However, Pendimethalin was found to be moderately persistent in the zone. This implied that the problem of choice of follow-crop does not arise and the compartments of the environment would be free from pendimethalin residues.