Assessment of Post-harvest Insect and Mould Infestation of Vigna subterranea
P. T. Nnaji *
Department of Microbiology, University of Calabar, Cross River State, Nigeria.
A. A. Brooks
Department of Microbiology, University of Calabar, Cross River State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Aims: This study was carried out with the aim of assessing the post harvest insect and moulds that infest Vigna subterranea.
Study Design: The randomized complete block experimental design with three replications for each variety was used to for the assessment of these varieties.
Place and Duration of Study: This research lasted for a period of four months in the University of Calabar, Cross River State Nigeria.
Methodology: Standard microbiological methods were used to obtain pure culture of fungi. Spore head and hyphae were chiefly compared with standard mycological atlas. Insects pest and infested nuts were sent to zoology department for identification of insect.
Results: Four varieties of Vigna subterranea namely; Cream Black Eye Variety (CBEV), Cream No Eye Variety (CNEV), Speckled Flecked Spotted Variety (SFSV) and Brown Variety (BV) were assessed for post harvest insect and mould infestation. Aspergillus niger, Penicillium species, Mucor species, Trichophyton species and Rhizopus species were isolated after plating in Sabouraud Dextrose Agar with antibiotics concentration of 50 µg/1000 ml. growth was not significant at P=0.05, but was significant at P=0.01. Cream black eye variety, brown variety and speckled flecked spotted variety were susceptibility to insect and mould infestation. Cream black eye variety had very high resistance to insect but was susceptible to mould infestation. Callosobruchus maculatus was identified as the insect that carried out the damage in Vigna subterranea.
Conclusion: Insect infestation in V. subterranea can result to increase in fungi growth. Cream no eye variety V. subterranea posses some properties that exhibits resistance to insect.
Keywords: Vigna subterranea, mould; insect, resistance;, susceptible, infestation, post-harvest.