A borrowed virus gives cowpea breeders a fast way to ask what a gene does

Cowpea — the plant behind black-eyed peas — puts protein on plates across tropical regions, feeds livestock and puts nitrogen back into soil. A team led by Ying Zhou at Zhejiang University has now adapted a virus that infects the plant into a handy lab tool: it temporarily quiets one chosen gene, without permanently changing the plant, so researchers can see what that gene actually does. The method worked in all seven varieties tried, the effect lasted at least eight weeks, and a simple needleless syringe delivers it in a few minutes per seedling. Using it, the team showed that four related genes help leaves make a defence hormone when insects attack — a clear pointer to genes worth chasing for tougher, pest-resistant crops.

SDG 2 · Zero hunger — Mechanism: tech innovation