Technology and prospects of cryopreservation of germplasm

Summary Entire plants have recently been regenerated from frozen cultures of protoplasts, cells, tissues and organs and stored at super-low temperatures for various lengths of time. This suggests the possibility of utilizing cryogenic methods for the conservation of important and rare germplasm, especially of the vegetatively propagated plants, which at present do not have any satisfactory method for their preservation. In addition, the freeze preservation offers a number of significant uses and prospects; (i) tissue cultures often show chromosomal variations, nuclear and ploidy changes, and mutations. Such genetic variables and cell lines which do not occur in nature can be picked out, banked and used in response to research needs; (ii) to maintain a cell line, it has to be transferred to a fresh medium periodically; the freeze storage would suppress cell division and thus the need for subculturing is avoided; (iii) at super-low temperatures the cells are in a non-metabolic state, which delays or virtually stops the ageing process, and thus the morphogenetic potential of cultures is retained; (iv) pathogen-free stocks could be frozen, revived and propagated when desired, this would be ideal for the international exchange of such materials; and (v) the freezing of pollen would solve some of the problems encountered with the incompatibility and pollen longevity.Ever increasing population pressures demand improving and evolving new cultivars. However, with this enthusiastic search for obtaining new plants, and rapid increase in their number, it is not only becoming difficult but at times impossible to maintain or preserve some of the stocks which at present, are not needed for breeding purposes. Thus, some of the germplasm which may not seem to be of importance today, but might be needed in future, is ignored or completely lost. Therefore it is for the purpose of preservation of materials which are threatened with extinction that Germplasm Banks need to be established.It is envisaged that freeze storage and tissue cultures would be a meaningful tool in experimental biology and agricultural research for the preservation and international exchange of important and pathogen-free germplasm.     

Properties and functions of the cyanogenic system in higher plants

Summary Cyanogenesis, the production of HCN is a trait that can be found in all the major taxa. The system is particularly important in higher plants, both in view of the specialized mechanisms found in plants and with regard to the physiological and ecological function of HCN production. The present paper discusses the long history of cyanogenic research, the distribution of the cyanogenic substances among the taxa of higher plants, their localisation in the plant organs and their biosynthetic pathways. The same topics are discussed with regard to the specialized -glucosidases found in plants that play a role in the catabolism of the cyanogenic substances and in HCN production.The physiological and ecological functions of the cyanogenic systems are discussed with emphasis on the few species studied so far that are polymorphic, i.e. contain cyanogenic and acyanogenic individuals in the same population. Although research in this area is still in its infanthood, it is clear that cyanogenesis is part of a complex system that among others, gives protection against particular groups of herbivores. Apparently the defensive system is under some kind of constraint, developmental, selectional, or both, that prevents plants from having an absolute defense against herbivores. One such constraint viz. a negative effect of the cyanogenic system on growth and/or reproduction is discussed in some length. A number of cultivated species, i.e. cassava (Manihot esculenta), sorghum (Sorghum spp) and lima bean (Phaseolus lunatus) to mention a few, are cyanogenic. Cyanogenesis in species used for human or lifestock consumption is generally considered an undesirable trait. On the other hand low levels of cyanogenesis may cause greater susceptibility to herbivores and consequently lower the yield. Apparently cyanogenesis is a character of interest for plant breeders trying to improve cyanogenic species.     

植物花粉影响因素和保存方法研究进展

花粉是植物种质的主要形式之一，包含该物种的所有基因类型。植物花粉的保存研究对完善种质资源保存方法及加速育种进程具有重要意义。为了满足种质资源保存以及杂交育种工作的需求，笔者阐述了花粉类型、基因型及化学成分、环境因素等对植物花粉生活力的影响；总结了植物花粉的收集和花粉生活力的主要测定方法以及有机溶剂保存、低压保存、低温保存、超低温保存等植物花粉的主要保存方法；提出超低温保存技术将成为花粉保存和研究的重要方向，仍需进一步深入研究植物花粉不同保存方法的保存机理。以期为研究不同植物花粉的长期高效保存方法提供参考。     

河北省珍稀濒危高等植物资源及其保护对策初探

根据河北省高等植物的地理分布、生态环境、种群数量以及资源利用现状,综合分析,提出了河北省珍稀濒危植物的受威胁种类和保护分级的标准,将河北省的70种珍稀濒危高等植物初步划分为3个保护等级。其中,河北省一级保护植物19种,二级保护植物22种,三级保护植物29种。分析了河北省珍稀濒危植物受威胁的主要原因,并在此基础上提出了保护对策。     

西安植物园展览温室植物选择及引种植物研究初报

为了更有效地进行植物多样性保护,充实现有景观,2006年西安植物园展览温室加大植物引种栽培力度,重新布展。目前共收集热带亚热带植物120科233属609种。其中兰科25属近60种,棕榈科14属29种,热带果树10科19种,多肉植物16科44属100余种,珍稀濒危植物22种。针对引种植物不同的形态、观赏特性、用途以及该温室特点共分了8个植物区域：多肉多浆区、棕榈植物区、四季花园区、观果植物区、附生植物区、荫生植物区、观叶观花植物区、悬垂植物区。温室今后应加大对专类植物以及珍稀濒危植物的保护力度,同时为有效利用有限的空间资源,草本植物、悬垂植物及附生类植物也应加强收集保存。     

西安植物园国家重点保护野生植物资源引种研究

摘要：本文结合珍稀濒危植物迁地保护的意义,概述了国家重点保护野生植物资源状况,对西安植物园多年来迁地保护的62种稀有濒危植物进行了引种适应性评价,并提出了植物园对于国家重点保护野生植物资源的保护对策。     

In vitro conservation of crop germplasm and the IBPGR databases

Summary The availability of a wide genepool is a prerequisite for crop improvement and the material involved is usually conserved in collections. The genetic resources of most crops can be conserved as seed but some vegetatively propagated crops and those that produce recalcitrant seeds cannot. In vitro (tissue culture) storage methods including cryopreservation in liquid nitrogen are being developed to conserve such problem materials in a complementary way to the maintenance of whole plants in the field. To aid the effective utilization of plant genetic resources, it is essential that as much associated information as possible be available to potential users — the plant breeders. The International Board for Plant Genetic Resources (IBPGR) has taken the lead in genetic conservation work including related areas of information management. A significant example is the promotion of in vitro conservation. The IBPGR's In Vitro Programme includes the establishment of databases holding data on technological developments. An international survey of the in vitro research community is conducted by questionnaire every two years. Data are gathered on the crop under investigation, field of interest, propagation method, problem areas, characterization, disease indexing, exchange of cultures, and storage of material under normal or slow growth conditions or by cryopreservation. The survey returns are computerized into databases that are available for consultation by request. Such databases have been compiled for in vitro research carried out in 1980, 1983 and 1985. The 1985 database, for example, covers the work of 589 scientists who contributed information on 654 different species. The most recent phase of the project involved the circulation of a new questionnaire to approximately 2,500 scientists in over 70 countries. All databases are available for search requests.     

Summary of Influencial Factors on Pollen Viability and Its Preservation Methods

植物花粉贮藏技术研究是开花生物学特性研究中的一项重要内容。在此，就植物花粉生活力的影响因素、花粉生活力的测定方法、花粉的贮藏步骤、方法进行了概述，列出了部分植物的花粉在不同条件下所能贮藏的时间和贮藏一定时间后的生活力状况，并指出了今后花粉贮藏的方向。     

普通小麦×东方旱麦草属间杂种长期保存技术及稳定性研究

对普通小麦×东方旱麦草这一完全不育属间杂种F1的无性系在培养基组成、 外植体大小对诱导率的影响和接种方法等方面进行了系统研究, 建立了对其进行长期保存的技术体系： 选择2n=35的F1正常植株为培养对象, 以1.1～3.0 cm的幼穗为外植体, 剪切足够细碎后接种于MS诱导培养基(MS无机元素+W14有机成分+400 mg/L LH+150 mg/L     

昆明犬遗传资源保存体系研究

通过对昆明犬遗传现状的分析,从活体保存、配子保存、DNA保存及数据库构建四个方面进行昆明犬遗传资源保存体系的研究。制定出昆明犬品种标准及核心群育种路线,同时采集系谱认证的昆明犬核心群和基础群个体,得到精液和血液样品,利用犬精液冷冻技术及DNA保存等技术手段构建样品信息库,并与全国警犬工作管理系统信息平台保持对接,初步建立昆明犬遗传资源保存体系,加快昆明犬种群的育种一体化进程。     

棉花群体冠层结构与干物质生产及产量的关系

对晋棉１０号品种９．０万～１５万株·ｈｍ－２５个群体密度梯度下的冠层结构、光合特性及其与干物质生产和分配的关系进行了研究。结果表明：在山西特早熟棉区适期播种条件下，晋棉１０号品种最适群体为１０．５万株·ｈｍ－２。该群体下，棉花冠层结构、光合特性及干物质生产与分配均优于其他群体，经济产量高出其他群体平均产量２５％以上。同时，提出了晋棉１０号品种适宜群体的若干指标，为确定棉花高产栽培措施及建立棉花生产管理模型提供了参考     

玉米种质保持中的适宜样本容量

用两个胚乳色基因型纯合的玉米品种不同比率的混合来模仿具有不同标记基因频率的玉米群体,通过田间试验、统计抽样以及Monte Carlo模拟研究玉米种质在繁殖前后标记基因频率的变化。两年田间试验和Monte Carlo模拟试验得到一致结论;在玉米群体田间植株中随机抽取8株上的全部种子或10株上每株25粒种子做样本可使群体中频率大     

云南野生茶树的地理分布及形态多样性

云南是世界茶树的原产地和起源中心,茶树种质资源种类众多,遗传多样性丰富,在茶学研究中占有非常重要地位。通过野外调查与文献资料的整理,对云南野生茶树资源的地理分布和形态多样性进行了调查,结果显示：（1）野生茶树在云南分布广泛,主要集中在西双版纳、普洱、保山等8个地区;（2）野生茶树与栽培茶树在形态上有明显差异;（3）云南野生茶树在形态分类上有22个种和2个变种,野生茶树呈现丰富形态多样性;（4）生境破坏是导致野生茶树数量锐减的主要原因,建议今后应加强珍稀濒危野生茶树种质的调查、收集保存、生态型及遗传多样性的研究和利用,为促进茶树新品种选育及茶产业可持续发展提供丰富的资源技术基础。     

A Community Development Approach to the Conservation and Improvement of Historic Conservation Areas

In this paper, we introduce the concept and notion of community development. We analyze the nature and character of Chinese historic conservation areas. We recommend using a community development approach in historic conservation area to transform historic conservation plans of physical environments into comprehensive community development plans. We encourage and promote the organized participation of community inhabitants in such plans and in the implementation of joint conservation and improvement tasks with the government for historic conservation areas.     

不同种冷冻保护剂嗜酸乳杆菌保存效果的比较研究

在相同的时间内,比较不同的冷冻保护剂配制和不同冷冻条件对嗜酸乳杆菌的保存效果。应用冷冻和低温冷冻2种冻存方法,于预定时间,分别对预设的7个不同冷冻保护剂进行复苏以及相关检测。冷冻保护剂分组为：DMSO-脱脂乳（1:9）、DMSO-液体MRS（1:9）、甘油-脱脂乳（1:1）、甘油-脱脂乳（8:2）、甘油-生理盐水（1:1）、甘油-液体MRS（1:1）、甘油-液体MRS（8:2）。试验结果显示：-80℃的试验组的嗜酸乳杆菌存活量大于除温度外同等条件下-20℃组的存活量。采用DMSO为冷冻保护剂、脱脂乳或液体MRS为冷冻介质的试验组的菌存活量明显大于其他试验组。本试验分组内,-80℃条件下,DMSO作为冷冻保护剂,冷冻介质为脱脂乳或液体MRS时,试验组的菌存活量明显大于其他试验组。     

The role of epibenthic predators in structuring the marine invertebrate community of a British coastal salt marsh

The marine fauna of salt marshes are subjected to predation by birds, tidally feeding flatfish, crabs, prawns and small gobiid fish. The role of these epibenthic predators in structuring the community was investigated using cages to exclude predators. A range of designs of cages and partial cages was employed to control for artefacts due to caging, and sufficient cages were employed so that each cage was only sampled once to prevent the compounding of disturbance due to predation and sampling. Two mesh sizes were employed, a fine mesh excluding epibenthic predators and a coarse mesh allowing access by small crabs, prawns and gobiid fish but excluding birds and larger fish. The exclusion was maintained for 2 years. The presence of any experimental structure had a significant effect on the sedimentary regime within the cage. Epibentic predator exclusion let to an increase in infaunal predator density, but had no significant effect on the infaunal deposit feeders. There was some evidence that predators limit the surface deposit feeding gastropood Hydrobia ulvae during the winter. The gastropod Littorina littorea responded positively to the presence of any caging structure; this may be the result of changes in the availability of food, as the sides of a cage support a diatom flora which this species can exploit. The lack of a response from the infaunal deposit feeders is attributed to their horizontal mobility within the sediment. The possible interactions between epibenthic and infaunal predators are discussed.     

化学固沙剂对退化沙地植物多样性与微生物多样性的影响

化学-生物固沙是一种有效固沙技术。为了解化学固沙剂对沙地植物多样性与微生物多样性的影响,以450、600、750 kg/hm²固沙剂和未喷施固沙剂(CK)为研究处理,生物、微生物多样性分析结果表明：应用固沙剂后群落重要值随着优势度增加而增加,随着优势度降低而降低;各处理均比对照群落高度、盖度、生物量有提高,表明应用固沙剂后对群落的生长具有促进作用,以600 kg/hm²处理最好。固沙剂喷施量的增加植物、微生物多样性都表现为减少,而植物、微生物优势度都表现为增加。植物多样性与微生物线性相关,同样植物优势度与微生物优势度存在线性相关。植物通过影响土壤环境,进而影响土壤微生物群落结构和多样性。     

Role of Arbuscular Mycorrhizae in the Alleviation of Ionic, Osmotic and Oxidative Stresses Induced by Salinity in Cajanus cajan (L.) Millsp. (pigeonpea)

Salinity stress causes ion toxicity and osmotic imbalances, leading to oxidative stress in plants. Arbuscular mycorrhizae (AM) are considered bio‐ameliorators of saline soils and could develop salinity tolerance in crop plants. Pigeonpea exhibits strong mycorrhizal development and has a high mycorrhizal dependency. The role of AM in enhancing salt tolerance of pigeonpea in terms of shoot and root dry weights, phosphorus and nitrogen contents, K⁺ : Na⁺, Ca²⁺ : Na⁺ ratios, lipid peroxidation, compatible solutes (proline and glycine betaine) and antioxidant enzyme activities was examined. Plants were grown and maintained at three levels of salt (4, 6 and 8 dSm^?1). Stress impeded the growth of plants, led to weight gain reductions in shoots as well as roots and hindered phosphorus and nitrogen uptake. However, salt‐stressed mycorrhizal plants produced greater root and shoot biomass, had higher phosphorus and nitrogen content than the corresponding uninoculated stressed plants. Salt stress resulted in higher lipid peroxidation and membrane stability was reduced in non‐AM plants. The presence of fungal endophyte significantly reduced lipid peroxidation and membrane damage caused by salt stress. AM plants maintained higher K⁺ : Na⁺ and Ca²⁺ : Na⁺ ratios than non‐AM plants under stressed and unstressed conditions. Salinity induced the accumulation of both proline and glycine betaine in AM and non‐AM plants. The quantum of increase in synthesis and accumulation of osmolytes was higher in mycorrhizal plants. Antioxidant enzyme activities increased significantly with salinity in both mycorrhizal and non‐mycorrhizal plants. In conclusion, pigeonpea plants responded to an increased ion influx in their cells by increasing the osmolyte synthesis and accumulation under salt stress, which further increased with AM inoculation and helped in maintaining the osmotic balance. Increase in the antioxidant enzyme activities in AM plants under salt stress could be involved in the beneficial effects of mycorrhizal colonization.     

广西野生稻资源原生境保存探讨

农业野生植物资源原生境保存是国际植物遗传资源界推崇的一种保存方式,开展野生稻资源原生境保存,能为野生稻资源利用提供丰富的优异种质与特异基因;为稻种基础理论研究提供更广泛的遗传多样性,具有十分重大的意义。本文认真探讨广西野生稻资源原生境保存方式,保存检测技术方法及保护制度运行机制等问题,并提出广西野生稻资源原生境保存的合理化建议。     

浙江省苍南县农作物种质资源调查与分析

为更好地挖掘、保护和开发利用苍南县重要农作物种质资源,2017年8月—2018年12月对浙江省苍南县7个镇17个行政村的农作物种质资源现状及利用情况进行系统调查,对种质资源进行收集,并对收集到的资源的种类、分布情况、植物学分类和部分特色资源进行整理和分析。结果表明,苍南县共收集到85份农作物种质资源,包括粮食作物41份、蔬菜26份、经济作物7份、果树11份,隶属于21科36属39种;按种质类型包括地方品种资源76份、野生资源9份。根据苍南县农作物种质资源现状,对苍南县地方品种和野生资源保护和开发利用进行讨论,建议通过建立资源圃和本地商业化开发利用等方式对地方品种进行原地保存,对部分地方品种或野生资源在资源采集地或原生境进行原位保护鉴定,确保本地优良种质资源的安全保存,实现种质资源可持续利用。研究结果可为苍南县农作物种质资源多样性研究、种质创新和开发利用提供参考。