RFLP mapping of the barley homeotic mutant lax-a.

The lax-a homeotic mutant of barley has flowers in which lodicules are replaced by stamens (giving five stamens per flower). RFLP mapping of an F2 population from a Bonus lax-a (1) x H. spontaneum cross showed that the mutation was on the short arm of chromosome 7(5H), closely linked to the centromere. An additional F2 population was used to show that the lax-a mutation gave the five-stamen phenotype in all flowers of 6-rowed spikes and that hoods were elevated and reduced in size in lax-a/Hooded double-mutant plants.