UV‑B Light Boosts Tea Plants’ Natural Defense

Tea leaves fight insects better when they get a quick dose of UV‑B light. Scientists used a tea plant and its common pest, the leaf moth, to see how the plants react. They set up a new lab kit that mixes smart scent‑detecting tools and fancy microscopes that can see chemical changes inside the leaves in real time. The scent sensors caught four specific smells—hexanal, (Z)-3‑hexenol, octanal and (Z)-3‑hexenyl acetate—that popped up most when the plants were exposed to 1. 2 kJ per square meter of UV‑B. Those smells are known to push insects away.The microscope showed that the plants made more jasmonic acid and a building block called L‑phenylalanine while making less protein. The leaves also changed how their tiny pores (stomata) opened, all of which help the plant resist chewing. Gene tests matched these changes, proving that UV‑B turns on special defense genes. By linking scent clues, inside‑leaf images and gene data, the work gives a clear picture of how UV‑B light helps plants stay strong without chemicals. It also shows that combining different science tools can speed up the search for eco‑friendly pest control in farming.