Impact of Gateway Organic Fertilizer on Herbivorous and Non-Parasitic Nematodes Associated with Telfairia Occidentalis Hook F. Field

Summary

Although fluted pumpkin (Telfairia occidentalis Hook F.) is cherished because of its nutritional, medicinal and industrial values, its profitable production and sustainability in agro-ecosystems is threatened by plant-parasitic nematodes. This study, therefore, tested the hypothesis that Gateway organic fertilizer can effectively suppress herbivorous nematodes while increasing the non-parasitic types. Gateway organic fertilizer (GOF) is one of the series of novel commercial fertilizers being utilized by organic farmers in South-western Nigeria. In this assessment, GOF was applied at the recommended rate of 5 tha-1. Application of 0 tha-1 served as the control. Treatments were laid out in Randomized Complete Block Design and replicated four times. Nematode identification, census and population analysis were conducted following extraction from soil collected from the field. Six cores were randomly taken per plot at 0-30 cm, bulked to obtain homogenous composite sample out of which 250 g sub sample was obtained for nematode extraction. The procedure was repeated once every month for three successive months. It was evident from the results that six (6) genera of herbivorous (plant-parasitic) nematodes were found associated with the fluted pumpkin, namely Rotylenchulus, Helicotylenchus, Hoplolaimus, Pratylenchus, Caloosia and Meloidogyne. Total riddance (100%) was observed in GOF-treated plots (P ≤ 0.05) compared to the control on herbivorous nematodes except for Helicotylenchus (100-36%). On the contrary the non-parasitic nematodes increased significantly (P ≤ 0.05) in the treated plots (from 0 to 10 and to 81). This work demonstrated that GOF caused fewer parasitic and greater populations of beneficial nematodes in fluted pumpkin.