8. The linkage relations of the following characters, which segregate sharply, are being studied:
- opaque1 (o1) - endosperm soft, starch, entirely opaque.
- opaque2 (o2) - similar in appearance to o1. Both give 25 per cent opaque in F2.
- threaded (th) - seedling and plant character. Very fine pin stripes similar to "threaded" cloth.
- semi-dwarf1 - plants about 2-1/2 feet high.
- semi-dwarf2 - plants about 2-1/2 feet high.
- Ragged2 (Rg2) - may be Rg1.
- lazy2 - may be la1.
- yellow dwarf (yd) about 23 per cent recombination between Y and yd.
- micropyle color (mc) intense red dot at micropyle when plants have large P. Tests are being made to determine whether an allelomorph or modifier of P.
- Additional tests are being made to determine the linkage relations of sp and lo with characters in the fourth linkage group other than su.