International Rice Research Institute, P.O. Box 933, Manila, Philippines
The lazy (la) mutant of rice is a well known marker of linkage group
VIII. During last few years, we obtained five new lazy mutants which were
induced through mutagenic treatments in different varieties of rice by three
scientists (Table 1). These five lazy mutants were crossed with RGS 14 (our
lazy tester stock) as well as with IR36 (non-lazy cultivar). The five F\1\s
with IR36 were normal indicating that all the five new lazy mutants are
recessive. All five F\1\s with RGS14, however, were lazy, thereby showing that
the new mutations occurred at the previously known la locus.
Table 1. New lazy mutants of rice tested for allelic relationships with la
(RGS 14)
============================================================================= RGS No. Parent variety Muitant obtained from ============================================================================= 54 Balilla (Mutant No. 19) R. Marie, INRA France 56 Cesariot (Mutant No. 28) R. Marie, INRA France 73 Americano (Mutant No. 16) R. Marie, INRA France 234 Norin 18 K. Pavithran, Calicut, India 259 CR115-32 R. N. Misra, CRRI, India =============================================================================