Plant defence against herbivory refers to the various adaptations and mechanisms employed by plants to deter or mitigate damage caused by herbivorous animals. It encompasses a wide range of strategies that plants have evolved over time to protect themselves from being consumed or damaged by herbivores.
One common form of plant defence against herbivory is chemical defences. Plants often produce toxic or distasteful compounds that deter herbivores from feeding on them. These chemical compounds can include alkaloids, phenolics, and terpenoids, which can be synthesized in different parts of the plant, such as leaves, stems, or fruits. Additionally, some plants can release volatile organic compounds that attract natural enemies of herbivores, further deterring them.
Physical defences, such as thorns, spines, or tough outer structures like bark or leaf cuticles, are another line of defence against herbivory. These structures can act as physical barriers, preventing direct access to the plant's tissues or making consumption more difficult and less rewarding for herbivores.
Plants can also use mechanical defences, such as rapid leaf movements or leaf abscission, to actively deter herbivory. Rapid leaf movements, often seen in certain carnivorous plants, can trap or entangle small herbivores. Leaf abscission, on the other hand, involves shedding damaged or infested leaves to prevent the spread of herbivores to other parts of the plant.
Furthermore, some plants have developed mutualistic relationships with beneficial organisms, such as ants or mites, which act as defenders against herbivores. These organisms are often attracted to the plant through the secretion of nectar or other rewards and provide protection in exchange.
Overall, plant defence against herbivory is a complex and multifaceted phenomenon, involving
