A group of hungry caterpillars climbed onto the tomato plant and ate the leaves frantically. The tomato buds and leaves are plump and emerald green, enough to fill the caterpillar’s belly.
However, soon, the caterpillars seemed to go crazy. They gave up the plump tomato leaves and turned to attack other caterpillars. In less than five minutes, a small caterpillar that was defeated was gnawed by a larger caterpillar and only a little body remains. The other caterpillars also began to kill and eat each other until only one winner was left…
In this chaos, the caterpillar family suffered heavy losses. However, this is not surprising, because studies have found that caterpillars can eat cannibalism when food is scarce. But why do caterpillars crazily cannibalize when food is so abundant?
Recently, researchers have found the “culprit” that drives caterpillars crazy-tomato plants.
It turns out that when a tomato plant is violated, it releases methyl jasmonic acid. This compound not only prepares nearby plants for defense, but also induces the tomato itself to produce a variety of toxic compounds, making its leaves less delicious and making Caterpillars can’t “snip their mouths”. In the end, these hungry insect larvae can only feed on each other to get nourishment in order to fill their stomachs.
In the experiment, the researchers found that if the tomato plants are sprayed with a higher concentration of methyl jasmonic acid, the caterpillars will eat each other more quickly. Due to the cannibalism of the caterpillars, after a week, these plants were also less infested by pests.
Scientists have always known that in the face of insect attacks, plant families will use various counter-attacks. Some release chemicals to make themselves less delicious, some will attract parasitic wasps, and wasps will lay eggs in the attacker’s body. When the wasp larva “broke out”, the attacker died. But this is the first time scientists have observed that plants can drive hunters crazy and kill each other.
However, researchers believe that in nature, the methyl jasmonic acid released by tomato plants is too slow, and that most of the leaves may have been eaten by the pests before preventing the invading of those greedy bugs. However, the sacrifice of individuals is conducive to the survival of the group. Those other tomato plants that have received the alarm signal can be prepared for defense in advance and release a large amount of methyl jasmonic acid. Once the caterpillar eats another plant, it may be affected by it. The leaves become difficult to eat and cannibalism occurs.
It seems that when plants face danger, they will not wait to die. Although they cannot run away immediately when facing danger like human beings, there are also many brilliant tricks to deal with the offenders. In the next step, researchers may learn from tomato plants’ promotion of insect cannibalism and develop more environmentally friendly pest management strategies.
