The role of plant health in the sustainable production of seed yams in Nigeria: A challenging nexus between plant health, human food security, and culture

Abstract

Yam (Dioscorea rotundata Poir) is a root and tuber crop throughout West Africa and has significant nutritional, economic and cultural value which underpin its importance for the food security of many people who live there. The crop is propagated vegetatively, primarily via the planting of small whole tubers (seed yams) and pieces (setts) cut from larger tubers.However, the use of such vegetative material means that a variety of pests (primarily insects and nematodes) and diseases (primarily fungal and viral) can carry-over and multiply from season to season. This paper sets out the plant health issues associated with yam, and how these have been addressed by improving the availability of good quality planting material Accepted ArticleThis article is protected by copyright. All rights reserved especially via the Yam Minisett Technique (YMT) and the more recently developed Adapted Yam Minisett Technique (AYMT). Both approaches are based on the planting of 'minisetts' treated with pesticide to produce seed yam free of pests and fungal pathogens, but there have been challenges regarding their adoption by farmers. The paper explores these challenges and how these attempts to improve plant health fit into a wider discussion of the sustainability of yam production in West Africa given that there are other driving forces of climate change, globalisation and urbanisation at play in the region.

Influence of Field and Storage Diseases and Pests on Tuber Yield and Quality of Exotic and Local Yam (Dioscorea spp.) Genotypes

“…About 44% of the total genotypes assessed had ≤10% tuber weight loss, of which three belonged to D. rotundata (TDr 89/02565, TDr 98/03015 and TDr 99-15), three belonged to D. esculenta (MOSLY045-12, MOSLY047-12 and KESLY011-12), three belonged to D. cayenensis (BOSLY071-13, MOSLY051-12 and BOSLY056-12), four belonged to D. bulbifera (MOSLY023-12, MOSLY044-12, MOSLY024-12 and KESLY09-12) and 37 genotypes belonged to D. alata (comprising eight introduced and 29 landraces). Our findings agree with Morse et al [50], who reported that most of the yam rot induced by insect attacks is mainly due to storage beetles (Coleoptera sp. ), mealy bug (Planococcus citri) and scale insects (Aspidiella hartii) during storage.…”

Viruses of Yams (Dioscorea spp.): Current Gaps in Knowledge and Future Research Directions to Improve Disease Management

“…Defining the socio-cultural systems and determinants that structure the exchange or purchase of seeds and agricultural practices could help identify the economic and social constraints that influence the deployment of control strategies. An example is the use of yam clean seeds, which has encountered difficulties in West Africa through its adoption by farmers because it implies changes from traditional practices such as using tubers from the previous harvest as planting material [117].…”

Evaluation of the Effect of Pre-Harvest Treatment on the Yield and Storability of Yam Tubers

“…Seed yam production using the minisett technology was introduced in Ghana and Nigeria [20], however, the small (25g) minisett size require special care and brings about yam tubers being often too small for planting as seed yams [21]. These are key obstacles to farmers towards adopting the technique [22]. A pre-harvest treatment may be defined as a system of existing technologies for agricultural raw materials production [23].…”