Identification of the Chromosomes of Groundnut, Arachis hypogaea L.

Abstract

Kawakami (1930) was the first to report the chromosome number of 2n=40 in the cultivated groundnut, Arachis hypogaea L. Husted (1931, 1933) observed a pair of chromosomes which were conspicuously smaller than the rest and designated them as ‘A’ chromosomes. He has also designated another pair of chromosomes having a long secondary constriction as ‘B’ chromosomes. Babu (1955) observed that the length of the secondary constriction varied in different varieties. D'Cruz and Tankasale (1961) observed in 4 varieties, 38 chromosomes as having median chromosomes while only one pair had a submedian centromere. They also found two homologous chromosomes with secondary constriction. Apart from these few reports, there is no detailed information on the morphology of the chromosomes, because of the difficulties involved in such studies. Interest in groundnut improvement programmes in recent years has prompted the development of rapid techniques for cytogenetic studies (Murty and Rao 1979, Murty et al. 1981). The possibility of identifying individual chromosomes of groundnut at pachytene was indicated by Murty et al. (1980). © 1982, Japan Mendel Society, International Society of Cytology. All rights reserved.