Effects of Green Manure of Gliricidiasepium (JacqKunth) and Leucaenaleucocephala (Lam De Wit), Arbuscular Mycorrhizal Fungi, and soil Amendments on the Physiological and Yield Characters of White yam (Dioscorearotundata - Poir) under Nutrient-depleted Soil

Abstract

Food shortage due to poor yield of food crops threatens the ever growing population in Africa and especially West African sub-region as a result of desertification, erosion over cropping, and land excavation. This present work intends to improve tuber yield in white yam under arbuscular mycorrhizal fungi, green manure of some leguminous (forage) trees and soil amendments in a nutrients-depleted soils. The study was carried out on a nutrients-depleted soil where land excavation had taken place behind the male hostel at the Federal College of Education, Abeokuta, Ogun State, South-West Nigeria. The land was cleared and heaped at 1mX1m and arranged in a completely randomized block design in three replicates. Data obtained were subjected to analysis of variance (ANOVA) and the means were separated using Duncan Multiple Range Test (DMRT). The results showed that green manure of Gliricidia sepium and Leucaena leucocephala enhanced chlorophyll production, water status and tuber weight in white yam. Other treatment that also enhanced white yam's physiological and yield characters are Glomus mosseae, G. etunicatum, poultry manure and NPK fertilizer. Though both organic and inorganic fertilizers enhanced tuber yield, the ecological hazards of inorganic fertilizers make organic fertilizers to be recommended for white yam's tuber yieldimprovement.