| Dendrocalamus hamiltonii is one of the three most important sweat bamboo species in the world, distributing in India, Burma, Nepal, Sikkim Bhutan, Laos and other countries of south-east Asia, generally, it is cultivated in purpose of shoot and timber in Xishuangbanna and Puer,Yunnan province of China, With growing rapidly, growing into forest fast, longer shoot-yield time, output high, nutrient and extremely good ecological benefits of conserving the source of water, conserving soil and water, beautifying the environments etc. The cultivated area expand constantly, while the research on genetic background and diversity is weak, and its taxonomy position wasn't clear by the reasons of different features basing on the Flora of China. In our study, amplified fragment length polymorphism (AFLP) marker was used in order to find out the genetic diversity and its taxonomy position, our research also put the importance on nutrition of shoot, the law of shooting and bamboo growth, management technology of bamboo plantation to enrich the theory of the artificial cultivation. The main results of this study are formulated as follows:1. The content of amylase and hydroxybenzene was high, which disturbed frequently the yield and quality of genome DNA when being extracted or being analyzed with AFLP, by researching on extracting DNA from leaves of D.hamiltonii a modified method was found to get high quality DNA in this paper, a system was also established, which was suitable for AFLP method to analyze the level and change of intra-specific genetic diversity.2. A total of 53 individuals from 8 populations in India, Vietnam and Xishuanbanna and Puer, China, were detected by eight pairs of AFLP primers, which were chosen from 64 pairs of primers. These primers generated a total of 1,728 bands, of which 1080 bands were polymorphic. The results revealed a high level of genetic diversity. At species level, the percentage of polymorphic loci (PPL) was 62.55 %, the effective number of alleles per locus (Ne) was 1.2056, Nei's genediversuty (H) was 0.158, and the Shannon's information index (I) was 0.1031, respectively. At the population level, the estimates for the population PPL = 20.08 %, H=0.069, I=0.2455, Na =1.6255 and Ne =1.2056. The coefficient of genetic differentiation (Gst) was 0.5862, this means 58.62 % genetic variation that occurred between populations. The gene flow (Nm) was 0.3529. These showed that the genetic diversity of Chrysanthemum is abundant; the genetic diversity of D.hamiltonii at the species level is higher than that at the population level, and the genetic differentiation among the population is very apparent.3. Thought cluster analyses by UPGMA showed that 53 D. hamiltonii cultivars could be divided into five groups where the genetic distance was 0.88. It was consistent with the morphologic classification based on petal type on the whole. Their origin was correlated with the cluster results to a certain extent. The India subpopulations were all divided into the same subdivision, Vietnam subpopulations as same as India; and the Menghai's subpopulation, Jinghong's subpopulation were divided into the Lancang-Menglian of Puer's population; the other subpopulation of Puer subpopulation was divided into Mengla's population. There was a possible correlation between genetic variance and habitat differences, genetic Identity and Genetic Distance between populations were estimated, and the results indicated that there was no correlation between geography distance and the genetic distance (r=0.227<0.7,P<0.05), and the genetic relationship between India population, Vietnam population and Chinese population was very close.4. D. hamiltonii shoot protein contained seventeen amino acids,of which 9 was essential amino acids.The total of amino acids (TAA) was 185.8 g.kg-1, essential amino acids (EAA) ,semi essential amino acids (SEAA) and the nonessentia1 amino acids (NEAA) was 185.8, 74.0, 15.8 and 111.8 g.kg-1,respectively, the EAA of D. hamiltonii shoot meet the standard of protein pattern recommended by FAO. N, P and K from shoot base to tip increased by 2.26, 2.11 and 1.45 times respectively. Nutrition concentration, including total soluble sugar, rough fibre decreased from shoot base to tip, but rough albumen increased. Total amino acids, necessary amino acids, semi-necessary amino acids from shoot base to tip gradually increased by 1.40, 1.43 and 1.385 times respectively, the change from tip to middle was little, while from middle to base was heavy .5. Young bamboo followed the growth the law of "slow-fast-slow", which lasting about 105 days. The findings during the observation for 50 days'indicated that the growth rate at night was 1.817 times than during the day, but after constant raining its growth rate change was small. Temperature and humidity were the key factors which affected the shoot to young bamboo.6. Researches on bamboo density and age structure showed that the shoot yield, bamboo number, individual weight, average diameter were correlated with bamboo density and age structure by regressive equation .The yield and quantity of shoot increased by the density of bamboo and the quantity of one-year-old bamboo increased. So we could forecast the yield will reach 13591.48 kg.hm-2 and economic profit will be 17668.92 yuan.hm-2, while the plantation density of bamboo is 284-409 cluster.hm-2, the structure of cluster is 6-9 cluters-1 and the ratio of one-year-old bamboo and 2-3 years old bamboo is 2: 1.7. The results from the experiment showed that nutrients of the shoot increased significantly with fertilizer application, the four kinds of fertilizer treatment play a good part in increasing N, P, K, protein, rough fiber and the protein water hydrolyzed amino acids, and advancing the bamboo shoots time, improving the amount and output of economic shoots, increasing economic value. While different fertilizer treatment influenced the yield and the quality of shoot , in inorganic fertilizer treatment ,N and protein content was the highest; in reunited fertilizer treatment, the amount of P, amino acids and the needed amino acids was the highest ; in the organism fertilizer treatment ,the sum of K,rough fiber, the half-needed amino acids was the highest; the sum of sugar of CK was distinctly higher than that in the fertilizer treatment. The influence of these four treatments on N, P, K content was discrepant in different shoot periods. On initial stage N, P, K was distinctly higher in fertilizer treatment than that of in CK, especially in the chemical treatment, the mixed fertilization of carbamide and compound fertilizer with 999.0 kg.hm-2 and livestock fertilizer with 3330 kg.hm-2 was the best fertilizer treatment; it improved the amount and output of shoots, increased the economic value.8. Containing bamboo stem earlier, the yield and quantity of shoot reduced distinctively, which decreased by 26.90 % and 47.48 % compared June with October. Containing bamboo stem at August, the weight of individual shoot was the heaviest, which was 1.46 kg, but the lightest at October, which was only 1.17 kg. One-year-old bamboo stem contained at August was the largest, the average diameter at breast height reached 7.91 cm, but only 6.55 cm at October. So it showed that contain bamboo stem at September could not only improve the amount and output of bamboo shoots of the year, but also ensure the amount and quality of growing bamboo that assure the amount and output of bamboo shoots next year.9. Height of earthed up effected the growth time of bamboo shoot underground. When the height reached l0 cm, bamboo shoot had good figure, high quality, large quantity and high price, but low inclusion quality. When the height was 0 cm only, bamboo shoot had low quality and bad figure, but high inclusion quality.10. Three soil cultivation treatments of fertilization were adopted, which were strip plough, overall plough and control plough, it showed that strip plough treatment was the best, which could bring the biggest profits, the income was 17,645 yuan.hm-2, the net profit was 3695 yuan.hm-2, the ratio of output to devotion was 1.26. So, strip plough can be widely used in production practices, it will not only increase the yield of bamboo shoots and economic value, but also reduce water loss,soil erosion and surface runoff, improve soil conditions and protect ecological environment.
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