Abstract
Pratylenchus coffeae and other nematodes cause a dry rot in the skin of yam (Dioscorea spp.) tubers which can compromise their usefulness as planting material. Dettol antiseptic and bleach, which are household disinfectants, were as effective as the nematicide oxamyl in suppressing P. coffeae populations and development of the dry rot in yellow yam (D. cayenensis) heads. There was somewhat earlier and a higher level of sprouting of heads dipped in these three chemicals, and these heads bore the heaviest sprouts. These heads, and those dipped in Jeyes Fluid, sustained their integrity for longer, compared with heads dipped in water or alcohol. The Jeyes Fluid dip appeared to injure the growing points on the heads, but by 14 weeks, all had recovered and sprouted. In a field trial, the Jeyes Fluid dip caused delayed sprouting of the heads, while the oxamyl dip encouraged early sprouting. However, by 25 weeks, all Dettol-, Jeyes Fluid-, or oxamyl-dipped heads had sprouted, and these plants produced the greatest weights of tubers; plants from Dettol-dipped tubers bore significantly greater tuber yields than all other treatments.
