Cytological investigations in a synaptic variant of Anogeissus sericea var. sericea Brandis (Combretaceae), an important hardwood tree of Rajasthan

Abstract

Studies of male meiosis in two varieties of Anogeissus sericea have led to the identification of a desynaptic variant tree of A. sericea var. sericea in the hills of Mt Abu in Rajasthan Province, India. The desynaptic variant exhibited a regular occurrence of univalents as opposed to bivalents in all the PMCs analysed, a convincing indication of failure of synapsis between homologous pairs of chromosomes. The number of bivalents influenced the orientation of the univalents at metaphase I and their regular disjunction at later stages. As well as the role of various causative factors such as temperature, humidity, nutrients, etc. leading to partial failure of synapsis (desynapsis), the possibility of adopting synaptic failure as a means of obtaining novel genetic variations of this economically important variety is discussed in detail. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 142, 103–109.