Which plant parts are most susceptible to injury from insecticides?

• A. Flowers and flower buds
• B. Roots
• C. Leaves
• D. Stems

Answer: (A)

Insecticide injury tends to show up first in the most delicate and actively growing parts of the plant, and in bloom those tissues are particularly vulnerable. Flowers and flower buds are developing rapidly and have fragile, sensitive tissues, so residues or contact from sprays can disrupt their growth, cause petal spotting or distortion, and even affect bloom development. Roots and stems are generally less exposed to foliar sprays, and leaves, while susceptible to some products, are not as prone to the kinds of injury that can disrupt flowering. So, the blooms themselves are the most likely to be injured.