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1.
[目的]对橡胶树种质的分子量与分布差异及其年度变化进行研究,为橡胶树优异种质挖掘、优良新品种选育和天然橡胶加工提供参考依据.[方法]以18份橡胶树的野生种质和栽培种质为研究对象,采取非刺激割制,在割胶期间的上中下旬采割胶乳,应用凝胶渗透色谱(GPC)进行分子量测定,分析分子量大小及其年度变化情况.[结果]18份橡胶树种质的数均分子量(Mn)、重均分子量(Mw)在种质间和年度内达极显著差异(P<0.01,下同),Mn年平均值为272414~764161,变异系数为0.09~0.37,Mw年平均值为2769600~3561437,变异系数为0.06~0.15;Z均分子量(Mz)在种质间差异不显著(P>0.05),但年度内差异达极显著水平,年平均值为7220414~7697966,变异系数为0.07~0.11;多分散系数(PDI)为4.7~8.8,栽培种质较野生种质具有更宽的分布.在年度变化上,大部分种质的Mn在开割前2个月较高,7月下降后并保持平稳,PDI则相反;Mw和Mz全年呈规律性波动态势,且均在7月中旬有明显的上升趋势.对测试月份分析发现,Mn、Mw和PDI年平均值与每月的上中下旬、代表性月份(5、7和10月或6、8和10月)测定平均值的相关系数均在0.950以上;Mn和PDI在代表性月份各测定1次,与年平均值的相关系数也在0.950以上(除6月上旬外),Mw则是5月下旬和7月、10月任一旬,以及6月下旬和8月、10月任一旬的平均值与年平均值的相关性更好,分别达0.927和0.913.18份橡胶树种质的GPC曲线各自呈现出一定特征,根据低峰情况可初步分为单峰和高低双峰分布2种类型,高峰大多出现在logMw为6.5处,低峰大多出现在logMw为5.4处.[结论]Mn、Mw和PDI可作为橡胶树种质胶乳特性的遗传指标,Mz不适合作为遗传指标.Mn、Mw和PDI年度内存在一定变化,可采取代表性月份测定或每月测定. 相似文献
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综述了国内外橡胶树分子生物学研究的进展,包括与橡胶生物合成相关的基因的克隆、测序与性质分析,以及分子标记在橡胶树选育种中的应用等。 相似文献
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LIZhiyong* Project Secretariat of ChineseSustainable Development Forestry Strategic Research Scientificand Technological Information Institute of Forestry Chinese Academy of Forestry Beijing P.R.China 《中国林业科技(英文版)》2004,3(3):19-23
1 STRATEGY BACKGROUND1.1 Quickening of Urbanization ProcessSince the reform and opening-up in China in 1978,economic community developed rapidly. By the endof 2003, GDP has exceeded $1 000 billion. With therapid development of Chinese economy, residentialmode focusing on rural population is now changing,urbanization process is quickening, traditional cityscale is expanding into metropolis (Tianjin, Xi’an,Chengdu, Chongqing, etc.) or super cities (Beijing,Shanghai, Guangzhou, etc.… 相似文献
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Construction of cDNA Library from Populus euphratica 总被引:1,自引:0,他引:1
Yu Guangjun Wang Yiqin Shen Xin * College of Biological Sciences Biotechnology Beijing Forestry University Beijing P.R. China Genetics Institute Chinese Academy of Sciences Beijing P.R. China 《中国林学(英文版)》2003,5(2):7-9
1 Introduction Populus euphratica is a salt tolerant tree species, which is mainly distributed in the desert regions in northwest China (Wei 1993). Moreover, it is the only large tree species, which can survive and develop into forest in these arid and saline-alkali areas. P. euphratica forest plays a very important role in restraining the expansion of desert, maintaining ecological environment in west China, protecting the biological diversity and raising the local people抯 living standard… 相似文献
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LIU Huifang* WEI Tianxing ZHU QingkeSoil Water Conservation Combat Desertification Laboratory Beijing Forestry University Beijing P.R.China 《中国林业科技(英文版)》2004,3(2):71-76
1 INTRODUCTIONThe Loess Plateau is the most drastic soil erosion regionin China, with the most severe water erosion. Thedistribution of types and intensity of erosion not onlyhave regional diversity but also have perpendicularvariation. In the small watershed, there are differencesin erosion characters among its upper, middle and lowerreaches. It is very significant for taking rationalmeasures of soil and water conservation and forpreventing soil and water loss to analyze the relationbe… 相似文献
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Dai Huanqin Lu Cunfu* Zhang Hui Zhang Xujia College of Biological Sciences Biotechnology Beijing Forestry University Beijing P. R. China Institute of Biophysics Chinese Academy of Sciences Beijing P. R. China 《中国林学(英文版)》2003,5(4)
Populus euphratica Olive is the only tree species that can grow in the saline land and also survive cold winters in northwest China, and it plays a very important role in stabilizing the vulnerable ecosystem there. A cell suspension culture was initiated from callus derived from plantlets of Populus euphratica. Cold acclimation was induced (LT50 of-17.5 ℃) in cell suspension at 4-5 ℃ in the dark for 30 days and the freezing tolerance increased from LT50 of-12.5 ℃ in nonacclimated cells to LT50 of-17.5 ℃ in cold-acclimated cells. Microvacuolation, cytoplasmic augmentation and accumulation of starch granules were observed in cells that were cold-acclimated by exposure to low temperatures. Several qualitative and quantitative changes in proteins were noted during cold acclimation. Antibodies to carrot extracellular (apoplastic) 36 kD antifreeze protein did not cross react on immunoelectroblots with extracellular proteins in cell suspension culture medium of Populus euphratica, indicating no common epitopes in the carrot 36 kD antifreeze protein and P euphratica extracellular proteins. The relationship of these changes to cold acclimation in Populus euphratica cell cultures was discussed. 相似文献
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SUN Qixiang ZHANG Jianfeng* . Silvicultural Laboratory of State Forestry Administration Research Institute of Forestry Chinese Academy of Forestry Beijing P.R.China . International Center for Bamboo & Rattan Bamboo & Rattan Laboratory of SFA Beijing P.R. China 《中国林业科技(英文版)》2007,6(1):82-86
Recently, due to more flooding, schistosomiasis is in expanding tendency in some areas. With Three Gorges Engineering progress, schistosomiasis will occurr potentially in Three Gorges reservoir. In order to control the disease, some methods must be applied, e.g. chemicals, biological measures. To some extent every way has its specific effect. However, the vital way is improving the environment and reducing the amount of snails. One of the effective ways is conducting forestry ecological engineering that focuses on snail control and schistosomiasis prevention. The practical ways cover such as pollution controlling, ditches surface hardening. Especially for water-level-fluctuation zone, conducting forestry ecological engineering to improve environment to prevent snails' propagation is significant and vital. By operating the project environment could be greatly improved and people's living conditions would be bettered. 相似文献