Kerr. E.A.  

Conformation that lateral suppressor (ls) is on chromosome 7.  

Lateral suppressor arose as a mutant in the greenhouse cultivar Antimold B (Brown TGC 5:6). It has been used widely but with limited success in breeding programs. For many years it was believed to be on chromosome 4. Taylor (TGC 3 1:19) presented evidence that it was on chromosome 7 close to flc. In 1986 I grew a small F₂ population of ls and gs in repulsion. The segregation was 50 ++, 25 + gs, 20 ls +, and 1 ls gs. This confirms that ls is on chromosome 7 but doesn’t locate it as precisely as Taylor’s data. This gene would make a good marker for the distal end of 7L.

Kerr. E. A.  

Linkage of upright pedicel (up) and jointless-2 (j-2) on chromosome 11.           

Randy Gardner reported a mutation of the Flora-Dade with upright pedicels (Hortscience 16:553-554, 1981) and proposed the symbol up. (This symbol was also proposed for upright growth [Kerr, TGC 32:34] which has since been assigned the symbol upg). Flora-Dade up which contains j-2 was crossed with the marker bip h and a small F₂ population grown. No linkage was detected between up and bip or h. The results for up and j-2 were 64 ++, 5+ j-2, 4 up + and 21 up j-2. This indicates close linkage with 9.3% crossovers. A three point test with other genes on 11S is needed to determine whether up is in the vicinity of tab or distal to j-2.