Isozyme markers in Saccharum spp. hybrids and Erianthus arundinaceus (Retz.) Jeswiet

Verification of the authenticity of the hybrid origin of progeny from interspecific or intergeneric crossing in introgression studies in plant improvement is essential before usage of such progeny. This study undertook to determine whether isozyme phenotypes verified the hybrid origin of apparent crosses between a clone of Erianthus arundinaceus (Retz.) Jeswiet and several Saccharum spp. hybrid clones. Starch gel electrophoresis was used to resolve 18 isozyme systems for markers that would distinguish E. arundinaceus from Saccharum spp. hybrid clones. Eight isozyme systems revealed 16 bands that were present in E. arundinaceus but absent from the sugarcane parents. When a population of putative E. arundinaceus × Saccharum spp. hybrid progeny was screened using these isozyme systems, none of the clones expressed the bands characteristic of E. arundinaceus. Thus, their intergeneric nature was disproven.