Final answer:
The use of systemic insecticides that are absorbed by the plant and then poison insects without harming the plant itself is indeed true. There are differences between chemical pesticides and fungal alternatives, with the latter offering multiple ecological benefits. Plants also produce their own natural defensive chemicals to deter herbivorous insects.
Step-by-step explanation:
The statement that plants can absorb pesticides and become poisonous to insects without harming themselves is true. This use of pesticides is a specific strategy where chemicals are designed to be taken up by plants and act as systemic insecticides. Such pesticides are selective in their action, often targeting specific enzymes or physiological processes unique to insects. Therefore, they typically do not harm the plant. A well-known example of a systemic insecticide is neonicotinoids.
Pesticides can vary broadly in terms of their effects and targets. While chemical pesticides are effective in controlling pests, they can potentially be harmful to humans if ingested and harmful to non-target organisms and the environment. On the other hand, fungal insecticides, which use fungi that naturally predate on insects and pathogens, might offer multiple benefits, including decomposing plant matter to enhance soil nutrients, controlling a broad spectrum of insects, and eliminating plant pathogens.
It is important to note that nature also provides examples of plants that produce their defensive chemicals. These plants have evolved over millennia to produce compounds that deter herbivores. An example is the monarch butterfly, which consumes milkweed and utilizes the plant's toxins to deter its predators, benefiting from the chemical defenses.