A major crop pest can make tomato plants lie to their neighbors
A major crop pest can make tomato plants lie to their neighbors
Whiteflies use plants’ chemical eavesdropping powers to get an easier meal
Not the tomato, please. Small insects known as silverleaf whiteflies can cause tomato plants to release misleading odors that render their neighbors susceptible to attachment.
Sap-sucking Undoubtedly insects, Bemisia tabaci is a threat to many different crops due of its invasiveness. However, when they strike a tomato plant, the plant begins to smell as though bacteria or fungi had attacked instead, resulting in a quiet shriek of smells. An international research team discovered that those fake odors prepare nearby tomato plants for attack, but not by an insect.
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These plants become ready to mount an immediate and powerful defense against an approaching disease. The plants’ ability to fight against insects is suppressed by the heightened alert, which “makes them far more vulnerable to the whiteflies when they arrive,” according to Xiao-Ping Yu, an entomologist at China Jiliang University in Hangzhou.
According to a report published March 25 in the Proceedings of the National Academy of Sciences by Yu and colleagues, tomato plants that spent 24 hours in a chamber with just the smell of a serious whitefly attack were only able to produce half as much of an insect-fighting hormone as plants that were suddenly attacked by insects.
Often, plant defense chemistry presents this binary choice. Plants often activate a system of defenses governed by the hormone jasmonic acid, or JA, to put up a strong struggle against insects. However, activating that system to its maximum capacity lowers the SA-controlled defenses, which are more effective against infections.
It’s possible that the plants’ pathogen preparation wasn’t a complete waste of time. Similar to mosquitoes, whiteflies spread viruses and other illnesses among plants. Sooty mold is drawn to even the tiny drips of honeydew, or whitefly pee.
According to research coauthor Ted Turlings, a chemical ecologist at the University of Neuchâtel in Switzerland, “Maybe the plant is more concerned about infections.” Because whitefly infestations start off strong, the false signal hurts the neighboring plants in the near term. However, the diseases that whiteflies transmit might eventually make the SA defenses useful. He continues, “We’ll try to investigate this in further studies.
Petra Bleeker of the University of Amsterdam is using a wild cousin called Solanum habrochaites to assist cultivated tomato plants in their defense against whiteflies. It produces its own terpene-based insect repellents in glands at the tips of many hairs. There are still traces of this hairy chemical in commercial tomatoes. She claims that if you press your finger on these hairs’ green areas, you will smell a tomato. The challenge will be to breed domestic plants with the capacity to produce repellents while avoiding the introduction of undesirable features.
Turlings is assisting struggling tomatoes in a different way. Machines with sensitive “noses” could alert us when particularly troublesome insects or pathogens enter because the smells that emanate from plants can be highly specific to what has attacked them. Turlings says, “It seems futuristic, but a robot might sniff the plants. He claims that even his human nose, which is quite skilled, can distinguish between the aromas generated by two corn stalks being attacked by two different but related species of caterpillars.
A farmer who keeps an eye out for particular scents may be able to detect insect incursions early and stop them. For pests like whiteflies that speed up their own spread by sending false signals to eavesdroppers, quick response may be especially crucial.