THE monosomic technique of identifying genes on chromosomes and developing
chromosome substitution lines (Sears, 1939 and 1944) has attracted the attention
of many wheat geneticists, since it provides a convenient way for establishing linkage
groups in this hexaploid plant and for transferring a desired chromsome alone from
one variety into another. Sears (1948) found that the variety" Timstein" carries
a gene for resistance to stem rust on chromosome X and this gene has been transferred
to a susceptible variety, Thatcher by chromosome substitution. Sears et al., (1957)
have demonstrated the presence of more than ten genes for seedling resistance to various
races of stem rust in the wheat varieties, Hope, Timstein, Thatcher and Red Egyptian.
Some minor genes may also be present on other chromosomes as indicated by Sears
and Loegering (1956) in the case of chromosome II and XX of Thatcher. Heyne
and Livers (1953), Wiggin (1955) and Knott (1959) identified the chromosomes
carrying genes for resistance in the varieties Pawnee, Kentana-52 and Kenya Farmer
respectively. Until now, attention has been mainly paid to stem rust and comparatively
little work has been done on leaf rust and more particularly on yellow rust (Puccinia
glumarum (Schm.) Erikss. and Henn. as will be evident from table 1. The present
study was hence carried out in crosses between Chinese Spring monosomes and Cometa
Klein, a yellow rust resistant wheat variety from Argentina.
Year: 1959
Volume: 59
Issue: 2
Article DOI: NA
Print ISSN: 0019-5200
Online ISSN: 0975-6906
M. P. SINGH and M. S. SWAMINATHAN info_circle