How do adult and larvae beetles damage plants?

Adult and larvae beetles primarily cause damage to plants through their boring and chewing actions. This behavior allows them to consume plant tissue, which can lead to significant harm depending on the species and the severity of the infestation. Adult beetles often have strong mandibles that enable them to chew through leaves, stems, and even roots, while larvae may bore into the plant material itself, disrupting the plant's normal functions, leading to reduced growth, wilting, or even plant death.

The other methods of damage listed are not characteristic of beetles. For example, while some pests do suck sap, this is more typical of insects like aphids or leafhoppers rather than beetles. Injecting venom is not a behavior associated with beetles, as they do not have venomous capabilities like certain other insects, such as wasps. Finally, although some beetle species may indirectly affect roots, the primary means of damage is through chewing and boring, which leads to direct injury to the foliage and structure of the plants. Thus, the choice highlighting boring and chewing accurately reflects the primary means by which beetles inflict harm on plants.