Morphology and cytology of flower chimeras in hybrids of Brassica carinata × Brassica rapa

Abstract

Hybridization between white flowered Brassica carinata and yellow flowered B. rapa were made, and the flower chimeras were observed in a few hybrids. The simple single sequence molecular markers verified the hybridity of those hybrids. Chimeras were justified and totally classified based on the morphological characteristics of the flower petals that appeared in the hybrids of B. carinata and B. rapa. Two kinds of flower chimeras were observed: one type was different flower petals were with different colour in one branch; another type was that yellow petals were with white variegations, but the variegation size and shape were different in different petals. The meiosis and mitosis analysis showed that the partial or complete separation of parental genomes inferred to occur in pollen mother cells, shoot and early-developed petals in the flower chimeral hybrids, which hinted that the occurrence of complete or partial segregation of parental genomes in the somatic cells might be the reason for the
production of flower chimera in the hybrids of B. carinata and B. rapa.