The incompatibility system in Italian red chicory (Cichorium intybus L)

As a result of an incompatibility mechanism which prevents both self-fertilization and intermating between plants with identical genotypes, inbreeding does not occur in Cichorium intybus. This self-incompatibility system complicates the production of inbred lines and the generation of f(1) hybrids in Italian red chicory. Histological observations on pollinated stigmas show that the incompatibility reaction in chicory is very rapid and either prevents pollen adhering to the stigmatic papillae or determines the arrest of pollen-tube growth on the stigmatic surface; incompatible pollen cannot reach the transmitting tissue of the style. Both histological and genetic analyses of F-1 progeny from a reciprocal cross between two unrelated plants suggest the occurrence of a sporophytic incompatibility system in Italian red chicory.