Control strategy against fungal pathogens of postharvest rot of groundnut (Arachis hypogaea L.using aqueous and ethanol leaf extracts of mahogany (Khaya senegalensis) in hong local government areaof Adamawa state, Nigeria

Abstract

Fungi are associated with heavy losses of seeds, fruits, grains, vegetables and other plant products in transit and storage rendering them unfit for human consumption. The used of synthetic fungicide has a great effect on human consumption, hence the need for safer control. A research was conducted in Hong local government area of Adamawa State of Nigeria (the most prominent groundnut farming community in the state). The following moulds were associated with postharvest groundnut rot in the seven districts of Hong local government area in the month of July 2016: Aspergillus niger (brasilensis), Aspergilus flavus, Penicillium chrysogenum, Rhizopus stolonifer, Paecilomyces lilacinus, Pseudallescheria boydii, Cylindrocarpon lichenicola and Scedosaporium prolificans. Therefore, the research sought to assess management of rot using plant extract of mahogany. Control trials were carried out using the extracts of leaf of mahogany. Growth of pathogens both in-vitro and in-vivo were significantly reduced by the plant extracts. Aqueous and ethanol leaf extracts reduced mycelial growth from 72.67 mm to 25.83 mm and 15.33 mm respectively for Aspergillus niger (brasilensis) (in-vitro) and from 55.00 mm to 28.58 mm by aqueous extracts and to 17.92 mm size of rot by ethanol extracts for in-vivo control. Efficacy of extract increased with concentration, while the local genotype was less affected by rot in comparison to Kampala variety. Therefore, mahogany aqueous and ethanol leaf extracts have been found effective against these pathogens and therefore the leaf is recommended for further research in order to formulate a control strategy for these pathogens.