Question

The application of synthetic plant hormone, like IAA, IBA, and NAA are best described as
A. Prevent early fruit fall before harvesting and is used to produce parthenocarpic fruit
B. Prevent early fruit fall only
C. To produce both seedless fruits and fruits with seeds
D. To produce large fruit

Answer 1

Hint: IAA is the main auxin in plants, regulating growth and developmental processes. IBA is used on various crops to stimulate flower development and the growth of fruits. Naphthyl acetic acid is a synthetic auxin plant hormone that is routinely used for the vegetative propagation of plants from stems and cuttings.

Complete answer: Auxin is a plant hormone (phytohormone). It is used in various processes of plant development. IAA and IBA are naturally occurring auxin hormones. NAA is a synthetic phytohormone. This hormone enhances fruit setting and helps in producing seedless, larger, and sweeter fruits. Fruits like orange, banana are produced seedless using these hormones. These hormones also help in the early maturing of fruits, thinning of blossoms. They also stop early fruit fall before harvesting. The regulation of the auxin concentrations creates a pattern-like system which helps in determining plant growth and development.
-IAA is often used in horticulture to promote adventitious root growth and is used commercially to create root stem cuttings and to promote uniform fruit and flowering growth. -IBA-derived auxin drives aspects of root development. IBA-derived auxin has strong roles in various aspects of root development, including regulation of root apical meristem size, root hair elongation, lateral root development, and formation of adventitious roots. -NAA is a synthetic plant hormone in the auxin family and is an ingredient in many commercial plants rooting horticultural products; it is a rooting agent and used for the vegetative propagation of plants from stem and leaf cuttings. It is also used for plant tissue culture.
 Thus, the correct answer is option A

Note: Plant hormones are signal molecules produced within the plant. They occur in extremely low concentrations. Hormones regulate cellular processes in targeted cells. Hormones also govern the formation of flowers, stems, leaves, the shedding of leaves, and the development and ripening of fruit.