Abstract
Introduction: Cashew (Anacardium occidentale L.) is an important tree crop and seedling survival is pertinent to successful establishment. Cashew seedling is infected by blight pathogens causing more than 60% seedling lost, however pesticides residues related issues and high cost of chemical necessitate efficacy trials of aqueous extracts of Mangifera indica, Azadirachta indica and Hyphtis suaveolens evaluated in-vitro on associated pathogens. Methods: Flora of blight-infected cashew seedlings was randomly collected from Cocoa Research Institute of Nigeria (CRIN) nursery between July and October, 2019. Mycoflora analysis was carried out in the plant pathology (Mycology) laboratory of CRIN. Antifungal assay of powdered Mangifera indica, Azadirachta indica and Hyphtis suaveolens were screened using aqueous extracts at 1:4 (w/v). Potato Dextrose Agar (PDA) amended with 1ml of 100%, 75%, 50%, 25%, and 0% of the extracts and Mancozeb (synthetic fungicide) as standard, 5mm mycelia mat disc of 10day old each of Lasiodiplodia theobromae, Fusarium pallidoroseum and Macrophomina sp. were placed at the centre of the amended media in triplicate and incubated 5-7days using complete randomized design (CRD). Mycelia extension inhibition and percentage growth inhibition (R) obtained. Results: Aspergillus niger, A. flavus, Fusarium oxysporium, F. pallidoroseum, Lasiodiplodia theobromae., Pythium sp., Rhizopus sp., Macrophomina sp. and Rhizotonia sp. were isolated. Fusarium pallidoroseum, L. theobromae and Macrophomina sp. screened with the varied concentrations of botanicals showed reduction in mycelia diameter; Mangifera indica (31.50%), A. indica (48.70%) and H. suaveolens (25.86%) on F. pallidoroseum favorably competed with mancozeb (39%) at 25% concentration while only M. indica was significant on L.theobromae(64.12%)and Macrophomina sp.(40.29%) and significantly different from control (0%). Conclusion: Aqueous extracts of M. indica, A. indica and H. suaveolens showed fungicidal potential on F. pallidoroseum and M. indica was significant on L. theobromae and Macrophomina sp.
Highlights
Cashew (Anacardium occidentale L.) is an important tree crop and seedling survival is pertinent to successful establishment
Azadirachta indica had 48.70% reduction in the mycelia extension of F.pallidoroseum at 25% phytoextract which exceed the synthetic fungicide, mancozeb at 39%
Mangifera indica had 64.12% reduction in mycelia extension on L.theobromae compared to the 48% of the mancozeb while M.indica had 40.59% reduction compared to 35% of mancozeb on Macrophomina sp
Summary
Cashew (Anacardium occidentale L.) is an important tree crop and seedling survival is pertinent to successful establishment. Cashew is indigenous to Brazil and commercially grown in Asia, Australia, South America and Africa [3]. This tree was introduced into Nigeria between 15 and 16 centuries by the Portuguese explorers purposely for erosion control and afforestation scheme of the defunct Eastern Nigeria [4]. Cashew is a prime tree crop of economic importance in Nigeria where more. The cashew industry provides up to 600,000 jobs which value at N24billion, as an export oriented-agricultural crop making an high contributor to Nigeria non-oil GDP [10]. Cashew is a fruit but food whose health must be aimed at protecting the crop from nursery to harvest
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call