Authors : Okereke V.C and R.C. Wokocha
Abstract: Aqueous extracts of ginger, neem seed, bitter cola and leaves of Hyptis suaveolens as well as captan and Trichoderma harzianum were evaluated in the greenhouse for their efficacy as soil drenches in the reduction of the damping-off disease of tomato incited by S. rolfsii. The experiment was laid out in a 6x3 factorial in a completely randomized design replicated five times. The results showed that soil drenching two days before inoculation with S. rolfsii gave disease reduction values which were similar in the treatments: T. Harzianum (67.1%), neem seed (62.4%), H. suaveolens (60.8%), captan (60.4%), bitter cola (60.1%) and ginger (57.4%). When soil drenches were applied on the same day as the inoculation, T. harzianum, captan and extracts of neem seed, H. suaveloens leaves and ginger significantly differed (p<0.05) from the bitter cola extract and the disease reduction values ranged from 40-60%. At two days after inoculation, neem seed extract, captan and T. harzianum significantly (p<0.05) reduced the disease giving disease reduction values of 53.3, 57.5 and 64.7%, respectively. Generally, the plant extracts showed selective fungi toxicity and were not phytotoxic to the tomato seeds.
Okereke V.C and R.C. Wokocha , 2006. Effects of Some Tropical Plant Extracts, Trichoderma harzianum and Captan on the Damping-off Disease of Tomato Induced by Sclerotium rolfsii. Agricultural Journal, 1: 52-54.