INFLUENCE OF SOME LEGUMINOUS TREES AND ARBUSCULAR MYCORRHIZAL FUNGI ON THE PHYSIOLOGY AND YIELD OF DIOSCOREA ROTUNDATA -POIR

Abstract

This work compares the physiological and yield characteristics of white yam (Dioscorea rotundata - Poir) under Arbuscular mycorrhizal fungi (AMF) inoculation, green manures of Gliricidia sepium, Leucaena leucocephala and other soil amendments. The experiment was conducted on the plot of land that had been overcropped, located at the back of the male Hostel, Federal College of Education, Abeokuta, Ogun State, Nigeria. The land was cleared and heaped at 1m x 1m apart. The experimental design employed was a complete randomized design in 5 replicates. The treatments were Glomus deserticola (GD), Glomus fasciculatum (GF), Gliricidia sepium (GS), Leucaena leucocephala (LL), Poultry manure (PM) and NPK fertilizers. Soils were dug from the heaps, 20 g of the inoculums of AMF (GD/ GF) were poured into the dug hole, seeds were laid on it and covered with soil (for GD & GF treatments). Others were applied at one week after sprouting. Growth and yield Parameters were determined at harvest while relative water and chlorophyll contents were measured forth nightly from 10 weeks after treatment. Data obtained were subjected to ANOVA while means were separated by Duncan multiple range test at P> 0.05. Results showed that growth, yield and physiological characters were enhanced in GD, GD+GF, GS and PM treated plants more than in inorganic fertilizers treated plants. There was a positive significant relationship between white yams growth, physiology and tuber yield. The study justifies the use of plant/animal manures and Arbuscular mycorrhizal fungi in place of inorganic fertilizers.