Question

Which plant hormones promotes seed dormancy, bud dormancy, and causes stomata closure
A. IAA
B. Abscisic acid (ABA)
C. GA ( Gibberellic acid)
D. Cytokinin

Answer 1

ABA plays a very important role in the closure of stomata in the plants and under the water stress and during the presence of opening the plants inhibits. Abscisic inhibiting the growth by the bud dormancy and helping to promote the plant seeds. In the growth regulation ABA plays a very important role during the process.

Complete answer:
In the smaller number of plants ABA acid obtained as the name from the abscission. The pathway has been elucidated in the plant genes for ABA biosynthesis and its sequencing. ABA acid is also produced by the biosynthetic mode different from the mode of ABA biosynthesis in the plants and in the plant pathogenic fungus. Terminal buds produced by ABA in the winter that developed the scales to protect the dormant buds during the cold season and slow the plant growth or directly primordial of the plant leaves. In the vascular column ABA inhibits the division of the cells and adjusts to cold conditions in the winter season by suspecting the both type of primary and secondary growth of the plants. Gibberellic is the process in which seed germination is inhibited by the ABA acid in the antagonism part of the plant.

Therefore the correct option is (B).

Note: Abscisic is the aid that is present only in the plants. In the development process, including the bud dormancy, stomatal closure, size and control of organs ABA play very important functions during the process. Plants that are responsible for the environmental stress including soil salinity, freezing tolerance, drought and heavy metal ions need a high amount of ABA acid.