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21.
以重瓣榆叶梅带腋芽的茎段作为试验材料,研究了不同外植体消毒方式、初代培养基激素配比和生根培养基激素配比对重瓣榆叶梅组织培养的影响。结果表明:1)先用75%酒精处理30 s,再使用0.1%升汞溶液消毒8 min或以2%次氯酸钠溶液消毒12 min,外植体感染率最低;2)茎段初代培养最佳培养基为MS+6-BA2.0 mg/L+NAA 0.05 mg/L,诱导率为89.30%;3)最佳增殖培养基为MS+6-BA 2.0 mg/L+NAA 0.1 mg/L+KT1.0 mg/L,增殖倍数为4.4,且生长状况良好;4)1/2MS+IBA 0.2 mg/L为最佳生根培养基;5)该研究建立了重瓣榆叶梅组培再生体系,为工厂化育苗与大面积推广奠定了基础。  相似文献   
22.
竹子一新种及二新组合   总被引:1,自引:0,他引:1  
本文报道了竹亚科镰序竹属一新种,即丰都镰序竹Drepanostachyum fengduensis Yi,它特产于重庆丰都县。它与坝竹(D.microphyllum(Hseuh et Yi)Keng f.ex Yi)的区别在于笋绿色,无紫斑,箨鞘无毛,箨片直立;叶鞘口两肩无繸毛;叶柄及叶片无毛,易于区别。将脱毛昆明实心竹Fargesia yunnanensis Hsueh et Yi f.detersa Yi et J.Y.Shi组合为脱毛实心竹Fargesia detersa(Yi et J.Y.Shi)Yi et J.Y.Shi,还将产于缅甸的Arundinaria elegans Kurz组合为雅致箭竹Fargesia elegans(Kurz)Yi。  相似文献   
23.
首次报道八角在江西赣南的播种育苗技术。  相似文献   
24.
Lichuan, located at the foot of the Wuling Mountain in southwest Hubei Province of central China, is well known in the world for the discovery of the living fossil Metasequoia glyptostroboides Hu & Cheng in the 1940s. Its natural habitat has been well protected by the Chinese government. In order to provide a scientific foundation for the protection of the Metasequoia resource, it has become necessary to analyze the changes in the original, natural Metasequoia mother trees (ONMMT) and their environment from 1948 to 2003. The results and countermeasures are as follows: First, the distribution areas have little changed, involving four towns/farmland, 45 villages, 5,746 individual trees in 1983 and 5,388 trees in 2003, covering nearly 600 km2, with an average density of less than 0.1 tree/hm2. The Metasequoia distribution consists of two main types: a scattered distribution type found mainly at the foothills or near houses, roads, villages and rivers while the population distribution type is found mainly at the mountains and valleys with a minority at low elevations in the mountains and basins. The largest Metasequoia populations have 105 and 123 trees. Second, in the past, attention was only paid to the protection of individual trees while the protection of the Metasequoia population and environment was neglected. This led to a shift from the past mixed forests to pure Metasequoia forests, with a simpler structure, reduced biodiversity and conditions non-conducive for natural renewal. From 1983 to 2003, 386 original Metasequoia mother trees died. So it is vital to enhance the protection of the only original Metasequoia population in the world and its habitat. Third, modern ecological means should be taken to protect the original Metasequoia population and its habitat. Research on the restoration and rehabilitation of Metasequoia vegetation should be carried out. Restoration and rehabilitation should be put into practice in the Xiaohe Valley, where the highest concentration of Metasequoia is found. Fourth, efficient measures should be taken to stop human activities that are harmful to Metasequoia and to improve the environment of ONMMT in order to promote the protection of the ONMMT population and its ecosystem. Eco-emigration and the return of marginal agricultural land to forestry can be practiced. __________ Translated from Acta Ecologica Sinica, 2005, 25(5): 972–977 [译自: 生态学报, 2005, 25(5): 972–977]  相似文献   
25.
In this study a reliable protocol was developed for the establishment of commercial in vitro cultures of Tripterygium wilfordii Hook f.. Juvenile shoots from one-year-old elite plants were used as the source of explants. New axillary shoots were obtained after 30 days of culture on a MS medium supplemented with BAP (2.0 mg·L–1) and NAA (0.1 mg·L–1). The optimal multiplication medium was a modified MS medium supplemented with BAP (1.0 mg·L–1) and NAA (0.1 mg·L–1). This yielded a multiplication rate of 2.4 fo...  相似文献   
26.
Metasequoia (Metasequoia glyptostroboides Hu et Cheng) is an important but endangered tree species. In a sense, the course of protection of the metasequoia can be considered a miniature of the history of the protection of rare Chinese plants over the past 50 years. The approval and establishment of the National Class Nature Reserve for metasequoia is a milestone in this course. A thorough understanding of this course is beneficial to design the correct future protection plans and for taking effective measures. In this paper the entire protection course of metasequoia is reviewed, three detailed measures are proposed according to the present situation and existing problems and discussed as follows. 1) We should reinforce unceasingly the establishment of National Nature Reserves of metasequoia, put emphasis on the protection of the original natural mother trees (ONMTs) of metasequoia, design farsighted projects to protect the ONMTs and strictly implement and enforce the regulations or laws regarding the protection of metasequoia. The establishment and functions of the organization should meet the demands of protecting the ONMTs and developing metasequoias. The budget should support and the quality of the personnel assigned to this task should satisfy the protection and development of the ONMTs. We should also promote the complete protection of the ONMTs at the same time and strengthen the protection and restoration of the ONMTs and their ecosystem in the Xiaohe valley, Lichuan County, Hubei Province, one of the natural concentration areas of ONMTs in the world. 2) A gene bank should be established for comprehensive protection of the genes of ex-isting original mother trees of metasequoia. 3) The key is to study the theoretical fundamentals of restoration and re-establishment of natural vegetation of metasequoia in the Xiaohe valley to harmonize the relation among environmental departments, forestry sectors, academies of sciences and other educational or research units, to carry out scientific research and strengthen academic exchanges to promote jointly the protection and utilization of metasequoia and other natural resources in China.  相似文献   
27.
In vitro propagation of a medicinal plant: Tripterygium wilfordii Hook f.   总被引:1,自引:0,他引:1  
In this study a reliable protocol was developed for the establishment of commercial in vitro cultures of Tripterygium wilfordii Hook f.. Juvenile shoots from one-year-old elite plants were used as the source of explants. New axillary shoots were obtained after 30 days of culture on a MS medium supplemented with BAP (2.0 mg·L–1) and NAA (0.1 mg·L–1). The optimal multiplication medium was a modified MS medium supplemented with BAP (1.0 mg·L–1) and NAA (0.1 mg·L–1). This yielded a multiplication rate of 2.4 for each subculture. Slightly more than 92% of shoots rooted when cultured on a modified MS medium containing IBA (0.2 mg·L–1) and acti-vated charcoal (0.5 mg·L–1). Activated charcoal promoted both a strong and a high rooting rate during the rooting phase. Plantlets were transferred to pots for a short acclimatization stage in a greenhouse where 95% of the plantlets survived. This highly reproduci-ble procedure can be adopted for large-scale propagation of T. wilfordii.  相似文献   
28.
油桐根腐病病原菌的研究   总被引:2,自引:1,他引:2  
陈守常  肖育贵 《林业科学》1989,25(2):113-119
油桐根腐病是油桐林的一种毁灭性病害。形态学和培养性状研究表明,致病菌为腐皮镰孢(Fusarium solani(Mart.)Sacc.)。将该菌与国内供试8个腐皮镰孢专化型菌株比较可看出,菌落生长较快,大型分生孢子短而粗,是一种短粗类型。其次,人工接种试验得知,此菌不侵染6科7属7种供试的专化型寄主植物;又经8个专化型菌株接种油桐试验,也不发生侵染关系。此菌仅侵害大戟科油桐属的油桐,是一种专化性病菌。再次,采用聚丙烯酰胺凝胶电泳分析表明,此菌与供试菌株的脂酶同工酶的谱带特征和相对迁移率均有明显的差异。由此,将油桐根腐病鉴定为腐皮镰孢一新的专化型,命名为油桐腐皮镰抱(Fusarium solani (Mart.) Sacc. f.sp.aleuritidis Chen et Xiao f.sp.nov.)  相似文献   
29.
紫叶桃是重要的园林彩叶树种,叶色美丽,观赏期长,具有很高的园林应用价值。以紫叶桃的叶片和嫩茎段为外植体,用不同浓度生长调节物质进行愈伤组织诱导试验,建立紫叶桃的再生体系。结果表明,诱导愈伤组织时,MS+2mg/LBA+1mg/L2,4-D对叶片诱导效果最佳,其诱导率达80%;MS+1mg/LBA+1mg/L2,4-D对茎段诱导效果最佳,其诱导率达100%。在MS+1mg/LBA+1mg/L NAA培养基上愈伤组织能直接分化出不定芽。  相似文献   
30.
以黄秆乌哺鸡竹为试验材料,研究了竹子个体结构因子之间的相关性,建立了黄秆乌哺鸡竹各个相关结构因子之间的线性方程模型.结果显示,竹子各个结构因子之间具有较好的相关性,其中胸径是影响竹子其他生物量因子的决定因子;单株竹秆质量、竹壁厚以靠近竹基部表现最为明显,是竹材具可利用性的有效段位.研究结果可为估算竹子的生物量与生产力、描述竹子的秆形特征、量化各结构因子之间的关系提供依据.  相似文献   
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