Recent findings that plants employ a drought-survival mechanism to also defend against nutrient-sucking pests could inform future crop breeding programs aimed at achieving better broadscale pest control.
Using an advanced fluorescent biosensor (ABACUS2) that can detect tiny changes in plant hormone concentrations at the cellular scale, scientists saw that abscisic acid (ABA), usually linked with drought response, started closing the plant's entry gates within 5 hours of being infested with spider mites.
Microscopic leaf pores (stomata) are important for gas exchange but are also the major sites for water loss. When there is a water shortage, plants act to conserve water by producing the drought stress hormone ABA to close their stomata.
Coincidentally, the closure of stomata also obstructs the preferred entry points for nutrient-sucking pests like spider mites. The two-spotted spider mite is one of the most economically damaging pests—it's not fussy and attacks a broad range of more than 1000 plants, including 150 crops.
Read more at phys.org