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为探索林下栽培金线莲[Anoectochilus roxburghii(Wall.)Lindl.]的方法,以肇庆广东星湖国家湿地公园核心区为基地,对低海拔(21~23 m)栽培金线莲的生长特性进行研究。结果表明,金线莲栽培地建议选择郁闭度约为65%的常绿阔叶林下。以原土壤+泥炭土(1∶1,V/V)为建畦基质,选择地上茎长≥4.16 cm,茎粗≥0.176 cm的Ⅰ级金线莲组培苗,在温度为18.3℃~24.5℃,湿度为84%~87%的3-4月份种植,成活率可达83.3%~86.7%,栽培120 d后植株地上茎长和单株鲜重分别增加了3.33 cm与0.71 g。5月份温湿度上升,金线莲栽培成活率显著下降(70.3%),且虫害高发。合理的林下栽培技术有助于开发利用和保护金线莲种质资源。  相似文献   
13.
Recent advances in molecular technology have revolutionized research on all aspects of the biology of organisms, including ciliates, and created unprecedented opportunities for pursuing a more integrative approach to investigations of biodiversity. However, this goal is complicated by large gaps and inconsistencies that still exist in the foundation of basic information about biodiversity of ciliates. The present paper reviews issues relating to the taxonomy of ciliates and presents specific recommendations for best practice in the observation and documentation of their biodiversity. This effort stems from a workshop that explored ways to implement six Grand Challenges proposed by the International Research Coordination Network for Biodiversity of Ciliates (IRCN‐BC). As part of its commitment to strengthening the knowledge base that supports research on biodiversity of ciliates, the IRCN‐BC proposes to populate The Ciliate Guide, an online database, with biodiversity‐related data and metadata to create a resource that will facilitate accurate taxonomic identifications and promote sharing of data.  相似文献   
14.
The orchid speices Gastrodia elata is a valuable traditional Chinese medicine and has been widely applied for treating a variety of diseases. The yield of wild Gelata is very limited since its vegetative growth is exclusively dependent on its symbiosis with the fungus Armillaria mellea, from which Gelata is able to obtain nutrients from rotten wood in the forest. To develop a standard for cultivating Gelata in large quantities, four factors that may influence the yield of Gelata need to be further investigated, including cultivation environment, inoculation volume of Armillaria, wood from different tree species, and the effect of fertilizer on the maturation of Gelata. To optimize these factors, a large scale orthogonal experiment was performed in the farmland of Xiaocaoba, Zhaotong, Yunnan Province. Among the four factors tested, inoculation of Armillaria played the most important role in the maturation of Gelata. The yield of mature tubers, in terms of both tuber weight and quantity, on open ground is greater than that in forested areas. Of the 12 tree species tested, Dipentodon sinicus stimulated the largest amount of growth of Armillaria and produced the greatest yield of Gelata in the farmland. In comparison to the other factors tested, fertilizer showed no effect on the yield of G-elata.  相似文献   
15.
不同栽培方式对籼、粳稻根表铁膜和根铁、镉含量的影响   总被引:7,自引:1,他引:6  
在Cd污染土壤中研究淹水、覆膜、覆草和湿润栽培对籼、梗稻不同生育时期根表铁膜Fe、Cd含量和根Cd含量的影响.结果表明,在分蘖期,梗稻根表铁膜Fe含量和根Cd含量在4种栽培方式中平均为6.37和25.49mg.kg-1。分别比籼稻的4.52和16.37mg·kg-1增加1.85和9.12mg·kg-1.在孕穗期,粳稻根表铁膜Fe、Cd含量和根Cd含量在4种栽培方式中平均为1.60、16.35和54.68mg·kg-1,分别比籼稻的1.06、9.56kg和43.31mg·kg-1增加0.54、6.79和11.37mg·kg-1.在灌浆期,梗稻根表铁膜Fe含量覆草和湿润栽培为0.89和1.00mg·kg-1,分别比籼稻的0.63和0.30mg·kg-1增加0.26和0.70mg·kg-1;梗稻根表铁膜Cd和根Cd含量在4种栽培方式中平均为15.23和73.68mg·kg-1,分别比籼稻的3.46和52.38mg·kg-1增加11.77和21.30mg·kg-1收获时。根表铁膜Fe含量淹水栽培的籼稻为1.21mg·g-1,比梗稻的0.65mg·g-1增加0.56mg·g-1,覆草栽培的梗稻为0.94mg·g-1,比籼稻0.55mg·g-1增加0.39mg·g-1;根表铁膜Cd含量湿润栽培的梗稻为7.96mg·kg-1,比籼稻的5.09mg·kg-1增加2.87mg·kg-1;根Cd含量梗稻在4种栽培方式中平均为54.53mg·kg-1,比籼稻的35.91mg·kg-1增加18.62mg·kg-1。  相似文献   
16.
香根草栽培平菇的研究   总被引:1,自引:0,他引:1  
本文以香根草为主要配方材料,以常规木屑为对照,设计了12个配方,栽培平菇,通过菌丝的长势和生长速度的不同,筛选适宜平菇生长的配方.研究结果表明,最适配方为香根草48%,类芦20%,芒萁10%,麸皮20%,碳酸钙1%和石灰1%;该配方菌丝长势旺盛、生长速度快,利用该配方栽培平菇,其生物转化率达到102.7%.  相似文献   
17.
组织学与胚胎学PBL教学对学生创新能力的培养   总被引:6,自引:0,他引:6  
中国医科大学组织学与胚胎学教研室承担了CMB03-#793项目,连续五年在临床医学七年制日文班实施了PBL(problem based learning)的教学模式,根据其教学特点确立了组织学与胚胎学(组胚)PBL教程,编写了"组织学与胚胎学PBL病例集"并制作了多媒体课件。学生在PBL中受到启发,激发了主动学习积级性,也制作了多媒体课件。同学课下查阅文献,准备资料。讨论病例分组进行,同学主持。大家踊跃发言,举证说明,用学得的知识,联系组胚理论去解释生命现象并和疾病相联系。我们对实施过PBL教学的几个年级的学生257人进行了追踪问卷调查,结果看出得到明显提高的依次是学生的主动学习的能力,独立查阅资料的能力、拓宽知识面、对相关领域感兴趣、分析解决问题的能力及对知识的理解能力。提高的相关指标就是创新思维的基础和前提。学生拓宽了知识面、开阔了视野,自然就会产生兴趣迸发出学习的生机去主动思维,也就有了分析解决问题的能力。由此产生不同以往的看法和想法,有了新的认识、新的观点和新的所为,丰富的想像力就会迸发出创造力,这些就是创新的萌芽。这是PBL教学带给学生的新的理念。刷新理念将会产生更多的创新。  相似文献   
18.
Cultivation of non-wood forest products (NWFP), although a veritable means of ecosystem and biodiversity conservation and improved natural resource management, has not been sustained in southern Nigeria (Nigeria’s major forest region) notwithstanding the unprecedented rate of depletion of the resource in the wild. For example, efforts in the past to support cultivation of NWFP in southern Nigeria under a USAID funded Cross River State forestry project, especially through nursery establishment for some rural communities, was not sustained as the initiative was abandoned by the participants. Hence to promote cultivation of NWFP, this study ascertained socioeconomic factors that influence cultivation of NWFPs. Multi stage sampling technique was used in selection of respondents (households) from two States: Cross River and Enugu States of southern Nigeria. A sample size of 400 households was used for the study. Probit and multinomial logistic regressions were used in estimating NWFP cultivation. The findings show that cultivation of NWFP was positively determined by gender, farming occupation (especially of women farmers) distance to forests where NWFP was collected, proportion of household food from NWFP, and medium wealth category. Age had a negative effect on cultivation until the age of 46 after which the effect became positive. In addition, household size, gender and farming occupation of household heads positively influenced cultivation of NWFP in plantations as against home gardens while gender and farming occupation had positive effect on cultivation of some stands of NWFP as against home gardens. Incorporating the findings of this study in future intervention project for NWFP cultivation will help sustain the initiative.  相似文献   
19.
本文通过对有机生姜生产基地建设的研究实践,总结阐述了有机生姜栽培中基地选择、土壤培肥、病虫草防治、轮作模式和姜田覆草等关键技术,提出了生产中的一些操作规范要求和建议。  相似文献   
20.
条斑紫菜抗高温和快速生长细胞株系HB的建立及栽培   总被引:1,自引:0,他引:1  
本文主要应用单细胞培养技术培育紫菜新品系,以建立紫菜细胞工程快速育苗系统。通过酶解技术分离出紫菜叶状体细胞,并进行多克隆,从中获得4个细胞纯系植株(HA,HB,HC,HD)。对该4个细胞株系进行了纯系培养,并对其细胞苗和丝状体的生长速度和抗高温(19℃,21℃,23℃,25℃)性进行了测定。结果显示,HB株系具有较高的抗高温性和最快生长速度。在1998年到2000年间,在江苏省启东县海丰海区对HB株系进行了海上栽培实验,结果显示,实验组的产量高于当地对照组产量,证明了条斑紫菜HB株系不仅具有较高的抗高温性,而且也有较快生长速度。本实验说明应用细胞工程进行条斑紫菜育种是一条很好的快速育种途径。  相似文献   
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