Research Papers: Comparison of Various Treatments for the Control of Pratylenchus coffeae in Yam

Abstract

Negro yam (Dioscorea rotundata) tubers were dipped for 30 min. in hot water (51C) and then in solutions of the nematicides oxamyl, phenamiphos, and diazinon or in solutions of the nematicides only. Tubers, treated with hot water and nematicides developed soft and wet roots whether planted or kept in storage. Root production was good in treatments with hot water, oxamyl alone, phenamiphos alone and the control. Populations of Pratylenchuscoffeae were significantly reduced by the hot water dip, but this treatment had adverse physiological effects on distal portions of tubers. Treatment with oxamyl at 1200 or 2400 ppm was the most effective since nematode populations were significantly lowered and plant growth was unaffected; phenamiphos and diazinon were ineffective treatments.