Analysis of shoot apical anatomic changes during the development of Brassica plants

In this study,we analyzed shoot apical anatomic changes during the development of Brassica plants including cauliflower(Brasscia oleracea L .var. botrytis),broccoli(B. oleracea L .var italica),Chinese cabbage (Brasscia compestris spp. pekinensis) and cabbage(Brasscia oleracea .L .). It has been showed that all of their apical meristems changed from the original tunica-corpus structure to the intergrade subarea,to typical 5- subarea structure and to 4-subarea structure when they went into reproductive development. The shoot apical meristem(SAM) cells were undergoing in different developmental way among these plants after they began reproductive development. The bilateral cells of sub-tunica of Chinese cabbage and cabbage divided into apical leafy primordial,in which lateral inflorescence meristem arised. While the bilateral cells of sub-tunica of cauliflower and broccoli divided into inflorescence meristem,which proliferated into curd or head. The results presented here provide the base for further investigation of anatomic identity of inflorescence phenotype formation and molecular events associated with meristem fate.