Identification of predominant fungi species infesting Bambara groundnut plants in South East Nigeria

University of Nigeria Nsukka (UNN), Nigeria

Right to left: Dr C. N. Onaebi; Mr Wisdom Akubue; Prof N. E. Abu; Prof C. C. Onyeke; Prof F. I. Akaneme; Mrs J. Chinekwu; Mr C. Maduakor (Research Associate) and Ms E. Agbo.

PROJECT OVERVIEW

Background

Bambara groundnut (Vigna subterranea) is a nutritionally rich grain legume crop native to Africa. It is tolerant to drought stress and can be cultivated under low input and marginal agricultural production systems in Africa and in Asia.

In Nigeria, the species is called Okpa in Igbo, Epa-Roro in Yoruba and Gurjiya or Kwaruru in Hausa. The grain is regarded as a source of complete and balanced diet. The total energy gains from Bambara groundnut grain consumption are the highest compared with other legumes (1). Among students, Bambara is popularly called ‘six-to-six’ (that is 6am to 6pm food) because when eaten as a breakfast, it fills the stomach and reduces hunger for a long time (2).

Fungal diseases have been reported as a major constraint on Bambara groundnut production in Nigeria.

Prof Florence Akaneme at the Bambara groundnut Pilot Project farm at the University of Nigeria.

Objectives 

To multiply the seed of the collected 316 accessions of Bambara groundnut.
To do a weekly field screening of a sample of 50 accessions of Bambara groundnut to record the field symptoms of fungal diseases that affect them.
To collect samples of the diseased leaves and roots from 10 randomly selected accessions, isolate the causative agents through culture and identify them through macroscopy and microscopy. The predominant pathogens will be identified.
To do a molecular identification of the predominant pathogens through sequencing of the Internal Transcribed Spacer (ITS) gene. ITS-4 and ITS-5 primers will be used to accomplish this aim.
To carry out a pathogenicity test in the screen house with the three most predominant pathogens from objective (3) above in order to find potential sources of resistance to the identified fungi.

(1) Majola, N. G., Gerrano, A. S. and Shimelis, H (2021). Bambara groundnut (Vigna  subterranea L Verdc). Production, Utilisation and Genetic improvement in Sub-Saharan Africa. Agronomy, 11: 1345. 

(2) Jidda, M. B (2022). Preliminary Assessment of Bambara groundnut [Vigna subterranea (L.) Verdc] landraces for incidence of pre-emergence damping-off disease and yield under irrigated and rain-fed conditions. Inter. J. Sustainabe Agric. Res, 9: 68-75.

Bambara groundnut Pilot Project farm at the University of Nigeria, 2023 growing season (i), Harvesting Bambara groundnut from farm at the University of Nigeria (ii), Plant Pathology Team about to commence Seedlings inoculations with fungi isolates (iii), Dr. Onaebi (Co-PI) inoculating seedlings with Phytophthora species (iv).