Cloning Of Flowering-related Genes In Phyllostachys Violascens

Phyllostachys violascens which has the characteristics of sprouting earlier, high yield, and remarkable economical benefit, is one of popular bamboo species for shoot production in China. It has been widely extended to Zhejiang and other southern provinces and produced great economic, social and ecological benefit. However, forest's degeneration or even death caused by Phyllostachys violascens flowering more and more popularly in recent years, which also resulted in lower and lower production.Floral formation is a very complex process controlled by genes in higher plants, and flowering is a result of floral genes expressed. Up to now, systematical theory on higher plants flowering mechanism but not on bamboo, has been achieved. Researches on bamboo flowering mostly rest on discussing the behaviors and causes of flowering, rarely on molecular mechanism. Hence, there are important theoretical and practical significances on carrying out the research in Phyllostachys violascens flowering-related genes and discussing the bamboo flowering mechanism.In this paper, histogenesis of floral development was studied by using scanning election microscopic and paraffin section methods, and then the floral genes were cloned with suppression subtractive hybridization , the results were as followed:(1) There is a certain relationship between different stages of floral development and the length of flower buds: l. Length <6mm, the differentiation of inflorescence had not started basically, the apical meristem was still a tunica-corpus structure; 2. Length 6～8mm, the stage of inflorescence differentiation, the lateral bud had formed; 3. Length 8～12mm, the stage of glumous flower differentiation, the stamen primordium and pistil primordium had formed; 4. Length >12mm, the stage of floral organs development.(2) We used Phyllostachys violascens's flowering and non-flowering bamboo strains came from the same rhizome for this study. SSH cDNA library was set up with Phyllostachys violascens flower buds(6～12mm ) as tester and leaf buds as driver by using SSH. After dot blotting, 29 positive clones were found. All these clones'function has been analyzed and forecasted after sequencing. Floral up-regulated genes of 19 out of 29 positive clones were confirmed by RT-PCR.