Improvement of Cocoyam Productivity with Effective Microorganisms (EM) and Indigenous Microorganisms (IMO) Manures

摘要

Cocoyam (Xanthosoma sagittofolium (L) Schott) being one of the six most important root and tuber crop has received very little attention due to low productivity, and availability of planting materials. The intensification of agriculture has led to the exhaustment of natural resources and the use of inorganic fertilizers for mass production leading to environmental and sanitary impacts with the water beds being polluted with chemicals and the population intoxicated by pesticides. In order to develop natural fertilizer to access sustainable agriculture, two types of manure (EM commercial one and IMO local one which enrich the nutrient quality of soil with bacteria, fungi and cynobacteria) were used to improve the productivity of Xanthosoma sagittifolium (cocoyam) taking into account morphological and agronomic parameters as well as disease incidence and some biochemical analysis. A randomized complete block design (RCBD) with three treatments (EM manure, IMO manure and control) and six replications was used. From the results obtained there were significant differences (p < 0.05) in the height of plants and stem girth throughout the experiment in all the plants treated with EM manure followed by those treated with IMO manure. Plants treated with EM manure also had the highest weight of cormels while the control plants recorded the highest disease incidence (3.05 ± 1.93). The control plants produced the highest phenol content (143.89 ± 39.3 μg.g^-1 FW) while peroxidase (POX) activity was highest in plants treated with IMO manure (8.99 ± 4.5 μg of CA of FW). Plants treated with EM manure had the highest pectin methyl esterase (PME) activity (5.48 ± 0.9 μg.mg^-1 FW) and no significant difference was noticed between control plants and plants treated with IMO manure. Application of EM and IMO manure increased crop productivity, reduced disease resistance, and tolerance to adverse soil and climatic conditions.