Screened Beans: Researchers Conduct Largest Ever Analysis of Disease Resistance in Bean Plants

From coffee rust to aflatoxin, Feed the Future is combating dangerous plant diseases that threaten global health and food security. One of the most important ways this happens is by developing and promoting food crops that are naturally resistant to disease.

It’s always good news when a disease-resistant plant shows promise to be used by smallholder farmers, but it’s even better when that process of identification can be carried out on a large scale. And that’s exactly what researchers are doing at the U.S. Department of Agriculture: last year, they conducted the largest screening ever for bean diseases in an effort to identify varieties resistant to halo blight, angular leaf spot and rust, three particularly problematic diseases thatare attacking dry beans in Eastern African countries.

In preparation for this field trial, researchers amassed an impressive collection of more than 400 bean varieties from North and South America, the Caribbean and Africa, many of which are well-suited to grow in Feed the Future’s African focus countries. To screen the beans for disease resistance, scientists plant different varieties and expose them to various diseases, discovering in the process which varieties are most genetically resilient.

Thanks to the size of the field trial sample, last year’s screening revealed 15 different bean varieties that are resistant to all three of the diseases in question, generating high hopes for the possibility of deploying these varieties among smallholder farmers in Eastern Africa.

Researchers have begun the process of mapping the DNA sequences of these resistant varieties so they can identify the specific genes that lead to resistance and, eventually, cross-breed bean plants exhibiting these genes with varieties already proven to be productive in Africa.

Did you know? 2016 will be the International Year of the Pulses. Pulses are edible seeds from legume plant pods such as common, string or kidney beans. Legume plants are a major source of vegetable protein and are unique in their ability to acquire nitrogen from the air in addition to the soil. Learn more.