A diverse approach to manage agricultural pests and diseases

The diverse varieties of individual crops represent a precious resource that poor farmers can use to manage pests and diseases, according to Devra Jarvis, the Bioversity scientist who is global coordinator of a project to research the ways in which farmers make use of diversity.

She was speaking at the wrap-up symposium of a three-year project that brought together farmers and scientists in four countries – China, Ecuador, Morocco and Uganda – to study how diversity of varieties in six crops: banana, barley, common beans, fava beans, maize and rice could be used to reduce pest and disease damage.

The overall conclusion, for most crops at most sites, is that the average damage due to pests and diseases was lower for farmers who grew three or four varieties. There was also less variability in the amount of damage. Some farmers who grew just one variety might be lucky and not suffer much disease; others lost almost their whole harvest. Farmers who grew more varieties had less disease overall and even the worst of them did relatively well. [Read more]