INFLUENCE OF SOIL AMENDMENTS IN THE MANAGEMENT OF STEM ROT (Sclerotium rolfsii) OF GROUNDNUT (Arachis hypogaea, L.) IN ISHIAGU, EBONYI STATE, NIGERIA.

Abstract

Experiments were conducted to determine the influence of soil amendments in the management of stem rot of groundnut caused by Sclerotium rolfsii in Ishiagu, Ebonyi state, Nigeria. The experiment consisted of seven treatments laid out in a randomised complete block design (RCBD) replicated three times. Soil samples were collected from the topsoil at a depth of 0 to 15 cm before application of the treatments to determine the physic-chemical properties of the soil. Potato dextrose agar was used to isolate the organism and the pathogenicity was carried out on a local variety (Ishiagu local). The data collected were subjected to analysis of variance (ANOVA) and the means separated using Tukey at p < 0.05. The results of the soil physical and chemical analysis showed that the organic carbon, organic matter, nitrogen and available phosphorus were very low. The result also revealed that the application of treatments gave a non-significant (p < 0.05) effect on percentage disease incidence. However, the untreated plot (33.33) had the highest disease incidence while plot treated with palm bunch ash (PBA) (6.25) had the least. Application of palm bunch ash showed significant effects on the disease severity. Moreover, the result of the number of harvested pods showed a significant difference (p > 0.05) among the seven treatments, plot treated with goat manure (1335.83 ton/ha) had the highest, followed by the plot treated with combination of goat manure and palm bunch ash (888.33 ton/ha) while the control (429.17 ton/ha) had the least. The pathogen S. rolfsii was isolated from the diseased groundnut tissue and the pathogenicity conducted on the local variety confirmed the organism as the causative agents of stem rot of groundnut. Therefore, the use of soil amendments such as palm bunch ash and goat manure could be an alternative means of managing the stem rot and increase the yield of groundnut by the small-scale farmers.