Studies On Physiological Characteristics And MRNA Differential Display Of Correlated Genes During Bolting In Radish (Raphanus Sativus L.)

Radish(Raphanus sativus L.) is a kind of popular vegetables with a long history of cultivation in China and plays an important role in production and supply, but bolting in advance brings grave losses in yield and quality. Bolting in plant is an important phase after transition from vernalization to sextual development and has tight contact relation with vernalization, flower bud differentiation and florescence. Sequently, it happens a series of pround changes in aspect of not only modality but also physiological and biochemical metabolization. Activity of many kinds of metabolization enzymes, content and component can be regulated by some correlated functional genes finally during flower bud differentiation, bolting and florescence and so on.In this paper, flower bud differentiation morphology in radish was studied in order to find an exact cut-in point of research on bolting development. The results was that morphological differentiation of stem stip was divided into three phase of vegetable growth, stem stip outspread and flower anlage differentiation. According to typical characteriscs of every period in single flower organ, ten levels was obtained detailedly including four phases of sepal anlage, stamen anlage, pistil anlage and petal anlage. It was different from previous conclusion that consistency of single flower organ differentiation is emphasized in our study. Just about in use of above advantage, standard about bolting materials is established in addition to small alteration. Furthermore it was observed that low temperature on germination seeds could accelerate course of flower bud differentiation and trend presents positive correlation between treat time and differentiation speed in a certain range.The dynamic changes of activities of polyphenol oxidase (PPO), ascorbate peroxidase (ASP) and content of souble sugar were analyzed in the bolting process of three late bolting inbred lines radishes. The results indicated that these two enzymes activity alternated each other during bolting growth and reconfirmed complexity of respiration metabolization. PPO activity took on a durative climb curve, especially went up exquisitely on the turning point of floral bud critical and bolting phase. On the contrary, ASP activity presented "downgrade" curve. It desent in the critical floral bud phase clearly and reached highest value until bolting and florescence. The content of soluble sugar was the lowest in the...