This diversity of vegetables is more than a local peculiarity – it could play an important role in ensuring adequate levels of nutrition and in meeting the challenges of agricultural production posed by climate change and soil degradation. Many traditional vegetables are known to have higher nutritional value than their commercial counterparts, and are well-adapted to local conditions, exhibiting resistance to drought, pests, diseases and marginal soil conditions. For example, the Mesoamerican shrub, the Mayan spinach (Cnidoscolus aconitifolius) contains exceptional levels of protein, vitamin C and iron, and provides leaves year-round with little water and in poor soil conditions. Traditional crops such as these could be strategic in helping more people meet the recommended levels of fruit and vegetable consumption, which is currently a global health concern.
Lack of information on traditional vegetables is, however, a major barrier to their use and promotion because it hampers a wider recognition of their values and understanding of how best to grow, process and market them. The study – recently published as part of the Agriculture Special Issue on Biodiversity of Vegetable Crops, A Living Heritage – showed that most of the world’s 1,097 cultivated vegetable species have received very little attention from research and conservation initiatives and are poorly documented by production statistics.
In particular, research and conservation of vegetables have largely focused on annual crops – plants that complete their life cycle within one year – while many vegetable-providing trees and shrubs remain effectively neglected. Furthermore, research and conservation initiatives have paid less attention to vegetables originating in Africa and the Asia-Pacific region than to species from other areas. Yet, native vegetables can be crucial for improving diet quality in these highly biodiverse regions, while vegetable-providing trees can support a holistic transformation of agricultural production for adaptation to climate change and provision of more nutrient-dense foods.