Hormonal Regulation of Abnormal Growth in Plants

Abstract

The varied abnormal growths in plants are characterised by extensive alterations and overgrowths due to the plant organ losing control over the growth potential of the affected area. Amongst the different types of abnormal growth, galls, hypertrophies, malformations and witches-brooms are worth mention. The various agents or conditions reported to act as incitants of abnormal growth in plants are: physical and chemical agents, genetic constitution, bacteria, viruses, fungi, insects, mites and nematodes. The abnormal growths are unique examples of complex interactions and mutual adaptation between the host and the pathogen. As a result of an attack on a plant by a pathogen the normal growth hormone balance is disturbed which brings about the change in the growth habit of the host. Within the context of this volume the text will be confined to a consideration of some of the important abnormal growths in plants and their hormonal regulation.