Sustainable Mass Production, Improvement, and Conservation of African Indigenous Vegetables: The Role of Plant Tissue Culture, a Review

ABSTRACT

African indigenous vegetables (AIVs) are plants grown and utilized traditionally by communities in Africa because they possess food, nutritive, or medicinal values. Seed dormancy, loss of biodiversity, high perishability of produce, low yield, and inadequacy of planting propagules, among other factors, are constraints against production and distribution of AIVs. This work examines the application of plant tissue culture (PTC) techniques for mass production of propagules, genetic improvement, and biodiversity conservation of AIVs because less than 5% have been tested for responses to PTC techniques. Applicable PTC techniques for sustainable production of AIVs include micropropagation, meristem culture, embryo rescue, shoot–tip culture, callus culture, somatic embryogenesis, protoplast fusion, in vitro flowering, and in vitro selection and mutagenesis. Shoot meristems, hypocotyls, petioles, immature leaves, cotyledons, axillary buds, seed, and epicotyls are suitable explants for PTC initiation. Specific benefits of these techniques include mass and accelerated production of disease-free propagules available in all seasons, an end to genetic erosion using biodiversity conservation and genetic improvement to overcome biotic and abiotic production constraints, and generation of hybrids of AIVs. Uniformity of plants and the ease with which AIVs germplasm are exchanged among African countries make application of the techniques desirable. Challenges facing application of these techniques in Africa are deficit of skilled human resources, underdeveloped laboratories and facilities, irregular power supply and unreliable consumable sources, high cost of PTC research, inadequate research funding, lack of research priority on AIVs, and confusion and controversy regarding PTC and genetic transformation.

KEYWORDS:

• Genetic improvement
• in vitro culture technique
• production constraints
• traditional vegetables