What is the definition of a plant growth regulator?

The definition of a plant growth regulator is a pesticide used to regulate or alter the normal growth of plants. These substances are specifically designed to affect the growth patterns of plants by either inhibiting or promoting various physiological processes.

Plant growth regulators can be utilized in a variety of agricultural and horticultural settings to achieve specific growth objectives such as controlling plant height, delaying senescence, or modifying root development. The ability to influence these growth processes is what sets plant growth regulators apart from other types of pesticides that primarily focus on pest control or crop protection.

In contrast, the other options describe different functions that may or may not relate to growth regulation. While some might promote flowering or enhance fruit size, these are not comprehensive definitions of plant growth regulators. Option A focuses solely on pest control, while options C and D highlight specific effects rather than the broader concept of altering plant growth. Therefore, recognizing the correct definition is essential for understanding the role of plant growth regulators in agriculture and horticulture.