| By means of conventional breeding, samples of 11 naturally distributed geographical populations of Dendrocalamus latiflorus Munro collected from 11 counties or cities of 5 provinces in natural distribution have been used to study the genetic variation of phenotypic traits among populations and within populations, to analyze the correlation between phenotypic traits and ecological, environmental factors and to find the geographical variation tendency in main phenotypic traits. Genetic diversity of 155 clumps from 11 populations of D.latiflorus Munro has also been analyzed by using RAPD molecular markers. Intraspecific hybridization and cultivation of seedling-plant have been carried out in main cultivated region. The main results for our research are as follows:1. There is significance difference among populations in all phenotypic traits. To all the variation coefficients, a majority of phenotypic traits has higher variable range above 10% , leader branching angle has the lowest coefficient of variation (C.V.) by 8.73% among populations, clear height has the highest C.V.by 72.23%. A certain extent variant range is also existed within populations. Whether among populations or within populations, the clear height has the highest variation.The correlation analysis has shown there is a significance correlation between each phenotypic trait and temperature, amount of precipitation, sunshine duration, frostless days respectively. While the regression analysis between traits and longitude, latitude and altitude has indicated that the regression2. coefficients between most of the phenotypic traits and longitude have reached significance or extremely significance level, but for latitude, only whole nodule number has close correlation and the relationship among clear height, under branch nodule number, whole nodule number and altitude have reached significance level, the longitude has great influence on the phenotypic traits, however latitude and altitude has less influence. The analysis has shown that the geographical variation trend of phenotypic traits has given priority to longitude, and no obvious variation in latitude and altitude.3. The clonal repeatabilities of all phenotypic traits are above 0.70, so it is shown that all the traits are under moderate or strong genetic control. The correlation analysis among all the traits indicats that there is a close or quite close relationship in phenotype and genetics. Higher clonal repeatability and close genetic correlation of traits have provided a scientific base for genetic improvement of D.latiflorus Munro.4. The higher quality DNA has been successfully extracted from D.latiflorus Munro with SDS method and a proper reaction system of RAPD molecular marker has been established. D.latiflorus Munro has a higher level of genetic polymorphism at the level of population and a great variation at the level of DNA. It has a PPB of 53.96%, a Shannon informative index of 0.5117, Nei's gene diversity (He) of 0.3430, total gene diversity (Ht) of 0.3443, gene diversity within populations (He) of 0.1930 and a Gst of 0.4394. Genetic differentiation is rather obvious among populations and the variance component among populations is 45.19%.We have regionalized the natural distribution of D.latiflorus Munro acording to the phenotypic variation combination by molecular variation. The whole natural distribution range of D.latiflorus Munro might be divided into three provenance zone: Yunnan provenance, Guangxi and Guizhou provenance, Guangdong and Fujian provenance. The third provenance could be further5. subdivided into Guangdong sub zone and Fujian sub zone.6. The finest flowering time of D.latiflorus Munro is at the last ten-day of November in each year after transplanting and then lasting about 4 months. The optimal time for controlled pollination is from 6 to 10 o'clock in morning of every day. Bearing percentage is higher at the current transplanting year of mother bamboo, with fertile percentage above 10%, and the maturation period of seed is much l...
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