Morphological and anatomical characteristics along with nutrient content changes during flower bud differentiation in Oncidium

The flower bud differentiation process of Oncidium 'Milliongolds' was studied using the paraffin cut method with changes of soluble sugar,soluble protein,and nucleic acid contents in leaves being determined.Results showed that the flower budding process could be divided into six differentiation phases:undifferentiated,inflorescence primordium,flower primordium,sepal primordium,petal primordium,and column and pollinia.Also,in leaves,soluble sugar decreased sharply till reaching a minimum at the flower bud differentiation period followed by a stable increase;soluble protein decreased sharply and then increased;maximum protein content occurred in the new bud sprouting period;and nucleic acid content declined overall.