8. The linkage relations of the following characters, which segregate sharply, are being studied:

  1. opaque1 (o1) - endosperm soft, starch, entirely opaque.
  2. opaque2 (o2) - similar in appearance to o1. Both give 25 per cent opaque in F2.
  3. threaded (th) - seedling and plant character. Very fine pin stripes similar to "threaded" cloth.
  4. semi-dwarf1 - plants about 2-1/2 feet high.
  5. semi-dwarf2 - plants about 2-1/2 feet high.
  6. Ragged2 (Rg2) - may be Rg1.
  7. lazy2 - may be la1.
  8. yellow dwarf (yd) about 23 per cent recombination between Y and yd.
  9. 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.
  10. Additional tests are being made to determine the linkage relations of sp and lo with characters in the fourth linkage group other than su.