Abscisic acid (ABA) is a growth inhibitor, often called the stress hormone. It induces and maintains dormancy in seeds and buds, so that seeds do not germinate during unfavourable conditions such as drought or winter. Gibberellins break seed dormancy by acting against ABA. Ethylene and IAA are not the main causes of seed dormancy. So seed dormancy is due to abscisic acid.
ConceptABA induces dormancy
Plant Growth Regulators: Abscisic Acid in past papers
2 questions from this chapter have appeared across 2 exam years.
