Brazilian Researchers Identify Wild Peanut Gene That Boosts Plant Immunity

Researchers at Embrapa Genetic Resources and Biotechnology have discovered a gene from a wild peanut ancestor that acts as a biological "alarm," significantly enhancing a plant's ability to survive drought and resist pests.

The gene, known as AdEXLB8, was isolated from Arachis duranensis, a wild ancestor of the modern peanut native to South America. Unlike traditional genetic modifications that provide a single line of defense, this gene triggers a mechanism called "defense priming." This process essentially creates a molecular memory, keeping the plant in a state of constant readiness. When under threat, the "primed" plants can react much faster to environmental stress or biological attacks without wasting the energy typically required for growth and productivity.

The AdEXLB8 gene was overexpressed in genetically modified tobacco, soybean, and peanut plants. The transgenic plants showed increased tolerance to two species of root-knot nematodes, the fungus Sclerotinia sclerotiorum, and droughts, even when those stresses occurred simultaneously. In the roots of plants where the gene was overexpressed, AdEXLB8 led to a 60% reduction in nematode infections and significantly higher tolerance to water scarcity and fungal diseases. Scientists noted that the plants maintained their high yields and quality even while under pressure. This breakthrough, currently being patented, can be applied to other crops, such as tomatoes, soybeans, and cotton.

For more details, read the article in EMBRAPA News.