What is a key attribute of insects and disease problems not associated with healthy plants?

A key attribute of insects and disease problems not associated with healthy plants is stress. When plants experience stress—whether from environmental factors, pests, or disease—they become more vulnerable to infestations and infections. Stress can weaken a plant's natural defenses, making it easier for insects to attack or for pathogens to proliferate.

Healthy plants typically have a strong immune response and can better withstand the pressures of pests and diseases. In contrast, plants that are under stress may exhibit symptoms like wilting, yellowing leaves, or stunted growth, which not only indicate underlying issues but also attract pests or are more susceptible to diseases.

While nutrition, water, and soil quality are important factors in plant health and can certainly influence the level of stress a plant experiences, they are not characteristics themselves in the same way stress is. A plant that is well-nourished, receiving adequate water, and growing in quality soil can still experience stress due to various external factors, thereby increasing its likelihood of suffering from insect or disease problems. Therefore, stress stands out as the most direct link to the health issues associated with plants and is crucial in understanding why some plants are more susceptible to these problems.