Cytomorphological Behaviour and Origin of Unusual Chromosomal Variants in Pearl Millet (Pennisetum americanum (L.) K. Schum)

Abstract

Cytogenetic manipulation induced in a crop may be useful in understanding the degree of tolerance of a crop to chromosomal changes, isolation of mutants, study of phylogeny and genetic nature of traits and productions of new cytogenetic stocks useful to the breeders. Cytogenetic studies on aneuploids (Sears 1956, Riley and Law 1965) are highly useful in crop improvement. Aneuploids have been used extensively in genetical and plant breeding researches (Hermsen 1970, Khush 1973, Rajhathy 1975 and Meijer and Ahloowalia 1981) and trisomics are the main aneuploids produced in case of diploids. In addition to different trisomics, other types of chromosome variants have been isolated in the progeny of triploid, translocation and other cytogenetical stocks of different plants (Gill et al. 1970, Jauhar 1970 in pearl millet; Ahloowalia 1966, 1970, 1971, 1982 in ryegrass; Ellerstrom and Sjodin 1966 in red clover; Rommel 1963 in barley and sugarbeet; Hagberg and Ellerstrom 1959 and Aastveit 1963 in rye). © 1987, Japan Mendel Society, International Society of Cytology. All rights reserved.