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排序方式: 共有310条查询结果,搜索用时 421 毫秒
1.
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
2.
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
3.
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
4.
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
5.
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
6.
7.
TILLING技术的发展及其在不同植物中的应用 总被引:1,自引:0,他引:1
TILLING技术(Targeting Induced Local Lesions IN Genomes)经过十多年的快速发展,已经应用到多种植物点突变高通量筛选与基因功能研究中,检测方法也逐渐趋于多样化,直接测序、毛细管电泳、高分辨熔解曲线等检测方法均得到了较多的应用。与此同时EcoTILLING、DeTILLING及iTILLING等相关技术的发展扩大了TILLING技术的应用范围。本文着重介绍了目前TILLING分析中用到的不同检测方法及相关生物信息学工具,详细评述了TILLING技术在模式植物、主要粮食作物、油料作物、蔬菜等其它作物中的应用与研究进展。 相似文献
8.
X.J. Fang * L.R. Jiang Hainan Institute of Tropical Agricultural Resources Sanya China Life College Xiamen University Xiamen Fujian China. 《分子植物育种》2007,5(2):209-210
Rice appearance trait is mainly mean grain length (GL), grain width (GW), ratio of length and width (L/W), chalkiness (CH) and transparence (TR). Appearance is the first impression, and rice appearance traits effect significantly the value of commodity. Hybrid rice is relatively low quality, especially on rice appearance quality,which restricts partially its extend and badly export of hybrid seed and rice in China.Shanyou 63, the most famous hybrid rice combination of China, could not be also sustainable application because of its poor qualities. In this studies, We attempt to improve appearance quality of the elite rice maintainer of Zhenshan 97B by using molecular approach of genomic interval targeted introgression. Three F2 populations were constructed to study the classical and molecular genetic of rice appearance traits, at the same time, molecular marker-asisted toimprove the main maintainer line, Zhenshan 97B were performed. There some following results:Three F2 populations were constructed based on crosses of Guangluai 4×Jiafuzhan (GJ popu.), Minghui 86×Jiafuzhan (MJ popu.) and Zhenshan 97B×Jiafuzhan (ZJ popu.). ZJ popu and GJ popu were produced to reconstruct the linkage maps related with rice appearance traits based on BSA, and detect QTL of target traits based on IM.In ZJ popu, 9 QTLs of target traits were detected. The interval, RM169~RM516 on Chromosome 5, was genetic locus of GW, L/W, CH and BW, and the explained variances were 10.9%, 14.9%, 12.0% and 14.2%, respectively.RM214 on chromosome 7, RM339 on chromosome 8 were genetic loci if CH and BW, and the explained variances were 9.4%, 10.0%, 11.0% and 12.1%. besides there is a genetic locus, RM347, of G/W on chromosome 3, and the explained varance was 10.3%. In GJ popu, 5 QTLs of rice appearance traits were detected. The interval, RM169-RM516 on Chromosome 5, were also the genetic loci of GW, CH and BW, and the explained variances were 9.0%, 12.5%, and 13.6%, respectively. RM264~RM80 on chromosome 8 was the genetic loci of GW amd L/W,and the explained variances were 14.7% and 13.4%. The genotypes of all QTLs, except RM214, from Jiafuzhan contributed to improving riee appearance traits.The research was to improve the rice appearance quality of Zhenshan 97B by introgressing QTLs of rice appearance traits from Jiafuzhan, a donor parent, by means of MAS in the process of recurrent backcrossing, 4 SSR markers were used to detect the target genotypes from donor parent, and 70 SSR primers to identify the genetic background of recurrent parent. Consequently, there were 19 target individuals in BC3, in which the mean value of GL, GW, L/W, CH and BW were 6.06±0.04mm, 2.50±0.02mm, 2.43±0.02, 29.5±2.7 and 29.4±2.7%, respectively,and the mean homologous degree (HD) to recurrent parent is up to 98.22%. Compared to Zhenshan 97B, GL, CH and BW decreased 0.17 mm, 34.9% and 34.5% respectively and however L/W increased 0.19. which accounted separately for 25.37%, 54.79%, 54.57% and 10.50% of thedifference of every trait between two parents. It is very luckly to find a individual, 13BC2-3BC3 line, whose GL, GW, G/W, CH and BW were 6.04 mm, 2.43 mm, 2.49,2.5% and 2.5% separately, There is very important signification for it to be used in hybrid rice breeding improving appearance traits. In the research, MAS efficiency of 3 loci (with 4 markers ) was 5.68% and coincident degree was 73.08%. 相似文献
9.
植物生长调节剂叶面喷施对小麦的增产效应 总被引:2,自引:0,他引:2
于小麦拔节期、灌浆期用植宝素、喷施宝、农特灵、禾乐、开特灵5种植物生长调节剂和尿素进行叶面喷施,结果表明,5种植物生长调节剂和尿素对小麦都有不同程度的增产效应,增产幅度为1.0%-10.8%,其中以禾乐的效果较好,增产10.8%。 相似文献
10.
我国作物航天育种20年的基本成就与展望 总被引:40,自引:34,他引:40
航天育种是我国科学工作者开创的农作物诱变遗传改良的一种有效新途径。经过20年的探索发展,已建立了全国航天育种研究协作网,航天育种研究工作取得了可喜的成果:在水稻、小麦、棉花、青椒、番茄、芝麻、牧草等作物上育成和审定了40多个高产、优质、多抗的农作物新品种,并开始在农业生产中发挥作用;获得了一批有可能对产量和品质等重要经济性状有突破性影响的罕见突变;航天诱变与地面模拟诱变育种技术创新取得显著进展;航天育种技术及其产品的知识产权保护与产业化、航天诱变机理探索等方面研究得到稳步推进。本文系统评述了我国航天育种20年来的基本成就,并根据当前研究和应用形势提出了发展战略。 相似文献