Microscopic droplets on the surface of leaves give refuge to bacteria that otherwise may not survive during the dry daytime, according to a new study published today in eLife. Understanding this bacterial survival strategy for dry conditions may enable scientists to develop practices that support healthy plant microbiomes in agricultural and natural settings.
The surface of an average plant leaf is teeming with about 10 million microbes – a population comparable to that of large cities – that contribute to the health and day-to-day functioning of the plant. Scientists have long wondered how bacteria are able to survive as daytime temperatures and sunlight dry off leaf surfaces.
“While leaves may appear to be completely dry during the day, there is evidence that they are frequently covered by thin liquid films or micrometre-sized droplets that are invisible to the naked eye,” says co-lead author Maor Grinberg, a PhD student at Hebrew University’s Robert H. Smith Faculty of Agriculture, Food, and Environment in Rehovot, Israel. “It wasn’t clear until now whether this microscopic wetness was enough to protect bacteria from drying out.”...
