Defence against herbivory refers to the various mechanisms employed by plants to protect themselves from being consumed by herbivores, primarily animals that feed on plant material. These defence mechanisms have evolved over time as a survival strategy for plants to ensure their own growth, reproduction, and overall fitness.
There are two main types of defence against herbivory: constitutive and induced. Constitutive defences are always present in plants, serving as a first line of protection. These defences include physical barriers such as thorns, spines, and trichomes, which deter herbivores from feeding on the plants. Other constitutive defences involve tough cell walls, lignified tissues, or waxy cuticles that make it difficult for herbivores to access and extract nutrients.
Induced defences are activated by plants in response to herbivore attack. These defences are triggered by chemical signals released by the herbivores or the damage they cause. Plants may produce defensive chemicals such as toxins, secondary metabolites, or volatile organic compounds to repel or harm herbivores. Induced responses can also include changes in plant morphology, such as rapid growth or increased production of defensive structures.
The specific defence strategy employed by a plant against herbivory depends on various factors including its evolutionary history, environment, and the type of herbivores present. Some plants may exhibit general defences that deter a wide range of herbivores, while others may have specialized defences targeting specific herbivore species.
Overall, defence against herbivory plays a crucial role in plant survival, allowing them to maintain their resources, reproduce successfully, and compete with other organisms in their ecosystem.
