Plant science for plant people.

One puff of bacterial vapor, and an agave plant remembers it for eight months; a tomato holds onto it for four and a half. Soil bacteria constantly release faint airborne compounds, and this week's featured work shows that a single early dose of one, ethyl isovalerate, primed seedlings to shrug off drought long after the treatment ended, with no repeat needed.

The numbers are hard to ignore: up to 2.65 times more tomato fruit under both normal and dry conditions, plus greener leaves and fuller water content in agave pushed to severe thirst. Not every vapor helped, one called nonanal actually set agave back, but the plants were clearly reading the air and rewriting how they'd meet the next dry spell.

Those same airborne conversations run all through the week. Isoprene gas leaking from one tobacco plant fattened its unmodified neighbors and drew helpful microbes to both root systems; distress signals from attacked plants pull defensive bacteria down toward the soil. The catch is that biodegradable plastics quietly muffle these root-to-microbe signals in tomato beds.

Feed your soil life, and it may spend months whispering drought instructions to plants you never hear it talking to.