4 - Physiological Regulation of Reproductive Growth

Abstract

This chapter describes the physiological regulation of reproductive growth in plants. The physiological regulation of reproductive growth is considered to be more complex than the regulation of vegetative growth, because the production of fruits, cones, and seeds requires successful completion of a series of distinct stages. These stages include initiation of floral primordial, flowering, pollination, fertilization, fruit set, and growth of the embryo, fruits, cones, and seeds. The internal resources needed to complete all phases of the reproductive process require carbohydrates, mineral nutrients, water, and endogenous hormones. Reproductive structures rapidly transport large amounts of reserve carbohydrates and current photosynthate into rapidly growing flowers, fruits, and cones. The amount of carbohydrates used in the metabolism and growth of reproductive structures varies with species and genotype, tree vigor, and age, time, and developmental patterns of flowers, fruits, and cones. Reproductive growth is regulated by a series of hormonal signals and interactions and the hormones produced by pollen tubes and seeds, which stimulate fruit set and growth.