鞑靼荞麦离体再生体系的建立

研究了苗龄、外植体、激素配比对鞑靼荞麦(Fagopyrum tataricum Gaertn.)离体培养的影响,初步建立了鞑靼荞麦离体再生体系.结果表明,鞑靼荞麦离体再生的最佳取材时间为苗龄6～8 d;诱导愈伤组织的最适培养基为Ms+2.0 mg/L 2,4.D+1.5 mg/L 6-BA,子叶诱愈率达75%左右,下胚轴诱愈率可高达86.62%;愈伤组织分化的最适培养基为MS+0.1 mg/L IAA+2.0 mg/L 6-BA+1.0 mg/L K1.+0.5 mg/L TDZ,来自下胚轴愈伤组织的分化率可达9.52%.下胚轴的诱愈率与分化率均高于子叶,更适于离体再生培养.培养基巾加入AgNO_3后,能有效降低褐化率.生根最适培养基为含有0.5 mg/L NAA的1/2MS培养基,生根率在50%左右.TDZ在诱导鞑靼荞麦的愈伤组织分化出芽的过程中起到明显的促进作用,可提高分化率约20%.表3图2参23     

黄姜组培快繁技术试验研究

分别以黄姜茎段、叶片、块根为外植体,进行无菌系建立、芽分化、生根等试验,探讨黄姜组培快繁技术.结果表明:(1)茎段在①MS BA1.0 mg.L-1 NAA0.2 mg.L-1(单位下同);③MS BA2.0 NAA0.2;⑤B5 BA1.0 NAA0.2;⑦B5 BA2.0 NAA0.2四个培养基上培养,均能诱导出愈伤组织,但尤以⑦号培养基长势最佳;而在这四个培养基上接种的叶片因为全被污染,无愈伤组织形成.(2)块根在②MS BA1.0 NAA0.5;④MS BA2.0 NAA0.5;⑥B5 BA1.0 NAA0.5;⑧B5 BA2.0 NAA0.5四个培养基上均不能诱导成愈伤组织.(3)愈伤组织在①~⑧号共八个培养基上均能分化出芽,但分化率不一,以③号最高(达100%),④号最低(25.0%).(4)当丛生芽长至高约3~4 cm时,转接到以MS或1/2MS为基本培养基、附加有不同浓度NAA和IBA的培养基中,进行生根培养.生长素NAA与IBA配合均能诱导生根,NAA的浓度增高对根的诱导有抑制作用,而且使苗的生长受阻,出现叶片卷曲现象,用1/2MS与用MS相比,用1/2MS生根更粗壮.(5)将经过炼苗的生根试管苗移栽到混有河沙和砻糠灰(体积比为1:2)的复合基质中,移栽后35 d成活率达到87%以上.     

发根农杆菌转化海边香豌豆及转化体的体细胞胚胎发生

将海边香豌豆无功苗的子叶和下胚轴切段在附加ρ（2,4-D)=1mgL^-1,ρ（6BA)=0.5mgL^-1的MS培养基上预培养3d，然后与发根农杆菌A4菌液共培养30min。洗涤之后，在附加羧苄青霉素的无激素的MS培养基上培养。7－10d后，外植体切面处长出许多毛状根。继代培养时生长旺盛，且产生许多侧根和分枝。志状根的诱导频率与无菌苗培养天数和外植体来源部位有关。子叶切块的诱导率明显高于下胚轴，16d龄无菌苗的子叶切块诱导毛状根的频率最高。乙酰丁香酮处理菌液可以有效提高子叶外植体的毛状根诱导频率。将毛状根切段培养在含有ρ（2，4－D）＝1.0mgL^-1的MS培养基上可诱导出愈伤组织。该种愈伤组织转移到含有ρ（2，4－D）＝0.3mgL^-1的MS培养基上培养时，诱导出了许多早期体细胞胚。检测的转化组织均含有农杆碱和甘露醇。图2表1参19     

唐菖蒲原球茎培养的研究

以唐菖蒲球茎芽切段为外植体在含有2，4-D的脱分化培养基上诱导的愈伤组织，可分化出具有双极性的原球茎．通过继代培养，选择了合适的培养条件：激素配比ρ（2，4-D）＋ρ（NAA）＝1mm／L＋0．5mg／L，ρ（Sugar）＝30g／L．pH5．8，θ＝21～26℃．光照液体浅层培养．在优化的条件下，利用双层板径向流生物反应器进行唐菖蒲原球茎培养，28d生物量增殖8倍，原球茎数增殖9倍．     

槐树组织培养中超度含水态苗发生与防止的研究

对槐树（Sophorajaponica）花药愈伤组织在培养条件下形成超度含水态苗的条件研究表明：短期培养的愈伤组织及在含有较低ρ（BA）的培养基上多形成正常苗，而经长期培养的愈伤组织及在含有较高ρ（BA）的培养基上产生了大量的超度含水态苗；在MS附加ρ（IAA）0．2mg／L、ρ（BA）5．0mg／L的培养基上，愈伤组织经连续1．5a以上的继代培养后，其表面产生的芽均为超度含水态芽；将这种愈伤组织和超度含水态芽转人含不同浓度和种类植物激素及生长调节剂的培养基后发现：BA和高ρ（KT）明显促进了超度含水态苗的形成；而一定ρ（NAA）和ρ（2，4-D）则显著地促进了正常苗的形成．对培养过程的观察显示：在各种培养基上形成的正常菌中，有一部分是由超度含水态的芽和苗转化而来，即由其顶端或腋生分生组织进一步发育转化而来，而另一些则由愈伤组织上重新产生．     

几种裸子植物胚乳愈伤组织的诱导

取裸子植物未成熟胚乳作为外植体，在改良MS、添加不同种类激素和不同浓度配比的培养基上．分别予以热激、光培养、暗培养和刻伤胚乳等多种处理进行培养．结果表明：刻伤胚乳和适时暗培养有利于愈伤组织发生；经过25～30d的培养，在ρ（NAA）＝0．5～0．75mg／L、ρ（2，4－D）＝0．2～0．5mg／L、蔗糖浓度5％的培养基上，油松、白皮松、青、华北落叶松以附加ρ（KT）1．0～2．0mg／L以及白、侧柏在BA与KT配合使用的培养基上，热激后暗培养，愈伤组织诱导频率可达86．4％．     

麻疯树愈伤组织的诱导及快速繁殖

以麻疯树(Jatropha curcas)的种子、叶柄、叶片为实验材料进行愈伤组织的诱导及快速繁殖的实验．用不同浓度的BA和IBA对其不同外植体进行试验，发现用MS培养基加0．5mg／LBA和1mg／L IBA对叶片的效果最佳．在相同BA浓度处理条件下，减小IBA浓度会对下胚轴愈伤组织的出芽产生明显的效果．叶柄要求的浓度更低，0．1mg／L BA和0．1mg／L IBA为最佳．不定芽在无激素的MS培养基中进行生根培养，通过几天的练苗过程，就能转到土壤中生长．图1表2参13     

诸葛菜下胚轴和子叶原生质体培养

以诸葛菜无菌苗的下胚轴和子叶组织为材料，分离原生质体，ＦＷ产量分别为５×１０８／ｇ和１×１０７／ｇ．下胚轴原生质体经纯化后在原生质体培养基中作液体浅层暗培养，培养密度为５×１０４／ｍＬ，培养第二天即出现第一次分裂，７～９ｄ后分裂频率约５０％，两周后出现大量细胞团；转入扩增培养基中，即扩增出大量小愈伤，植板率约为５％；愈伤转入分化培养基后即可诱导分化成苗，分化率达１００％，随后转到生根培养基中，即形成完整植株．子叶原生质体的培养方式与下胚轴原生质体培养基本相同，结果也类似．     

青蒿试管苗开花及用花器官为外植体诱导丛生芽生产青蒿素

将培养于MS培养基上5wk的青蒿试管苗置于光周期13，光强6000lx，温度为26℃（昼）和22℃（夜）的条件下，成功地诱导其开花，利用不同发育阶段的花蕾和花器官为外植体诱导丛生芽，发现不同浓度（ρ）的6－BA对丛生芽的诱导率和青蒿素的生物合成有重要影响。结果表明：以花蕾为外植体诱导丛生芽的最佳培养基是：MS附加4.0mg L^-1的6－BA和0.05mg L^-1的NAA；但当ρ（6－BA）在0－0.5mg L^-1之间时，有利于青蒿素的合成ρ（6－BA）=0.5-4mg L^-1时抑制青蒿素的生命合成，丛生芽中促进青蒿素合成的最佳ρ（6－BA）为0.5mg L^-1，用HPLC法测定发现用此法得到的丛生芽青蒿素的含量比直接利用叶片诱导的丛生芽青蒿素含量高1倍。     

麻疯树成熟胚乳再生植株及其气孔分析

对麻疯树成熟胚乳进行组织培养获得胚乳再生植株,并对其气孔进行分析.麻疯树成熟胚乳在25℃、12 h光照条件下培养7 d愈伤组织诱导完成,2,4-D浓度为2.0 mg L-1的MS培养基愈伤诱导效果最好,诱导率达89.29%.愈伤组织在含BAP的改良培养基上培养至黄绿色后转入分化培养基,在含IAA 0.25 mg L-1和ZT 1.5 mg L-1的WPM培养基上不定芽分化率达32.50%.将分化的不定芽从愈伤组织上剥离后转入含IBA、BAP和GA3的培养基上进行芽伸长培养.取胚乳不定芽叶片接种在含IBA 0.1 mg L-1、BAP 0.5 mg L-1和TDZ 0.5 mg L-1的MS培养基上诱导生芽后,再转入含IAA 0.25mgL-1、KT 0.5mg L-1、BAP 1.0 mg L-1和GA3 0.25 mg L-1的培养基上进行丛生芽的诱导,成芽率为85.2%.这些芽在含0.1 mgL-1 IBA的1/2 MS培养基上生根,大约有37.5%的芽生了根,平均有5.2条根系形成.与母本植株相比,再生的胚乳植株保卫细胞更大,且气孔密度减小.图2表6参24     

Achieving Open Access to Conservation Science

Conservation science is a crisis discipline in which the results of scientific enquiry must be made available quickly to those implementing management. We assessed the extent to which scientific research published since the year 2000 in 20 conservation science journals is publicly available. Of the 19,207 papers published, 1,667 (8.68%) are freely downloadable from an official repository. Moreover, only 938 papers (4.88%) meet the standard definition of open access in which material can be freely reused providing attribution to the authors is given. This compares poorly with a comparable set of 20 evolutionary biology journals, where 31.93% of papers are freely downloadable and 7.49% are open access. Seventeen of the 20 conservation journals offer an open access option, but fewer than 5% of the papers are available through open access. The cost of accessing the full body of conservation science runs into tens of thousands of dollars per year for institutional subscribers, and many conservation practitioners cannot access pay‐per‐view science through their workplace. However, important initiatives such as Research4Life are making science available to organizations in developing countries. We urge authors of conservation science to pay for open access on a per‐article basis or to choose publication in open access journals, taking care to ensure the license allows reuse for any purpose providing attribution is given. Currently, it would cost $51 million to make all conservation science published since 2000 freely available by paying the open access fees currently levied to authors. Publishers of conservation journals might consider more cost effective models for open access and conservation‐oriented organizations running journals could consider a broader range of options for open access to nonmembers such as sponsorship of open access via membership fees. Obtención de Acceso Abierto a la Ciencia de la Conservación     

Rapid,recurring, structured survey versus bioblitz for generating biodiversity data and analysis with a multispecies abundance model

A bioblitz inexpensively and quickly generates biodiversity data, but bioblitzes are often conducted with haphazard, unreplicated sampling. Results tend to be taxonomically, geographically, or temporally biased, lack metadata, and consist of lists of observed taxa that do not enable further analyses or correction for imperfect detection. A rapid, recurring, structured survey (RRSS) uses a structured sampling design and temporal and spatial replication to survey randomly selected sites on a conservation property. We participated in a loosely structured bioblitz and a subsequent RRSS at Big Canoe Creek Nature Preserve in Springville (St. Clair County), Alabama (USA) to compare observed richness derived from the 2 survey approaches. The RRSS data structure enabled us to fit models that accounted for imperfect detection to estimate abundances, occupancy probabilities, and habitat associations. The loosely structured bioblitz data could not be used in such models. We present a new integrated multispecies abundance model that we applied to avian RRSS data. Our model extension enables estimation for the community, employs data augmentation to estimate the number of undetected species, and incorporates covariates. The RRSS generated a more comprehensive and less biased list of observed taxonomic richness than the loosely structured bioblitz (e.g., 73 vs. 45 bird species and 104 vs. 63 insect families from the RRSS vs. loosely structured bioblitz, respectively). Models fit to the RRSS data identified seasonal patterns in avian community composition and allowed for estimation of habitat–occupancy relationships for insect taxa. The RRSS protocol has potential for broad transferability as a standardized, quick, and inexpensive way to inventory biodiversity and estimate ecological parameters while providing an outreach opportunity.     

Compliance with and ecosystem function of biodiversity offsets in North American and European freshwaters

Land-use change via human development is a major driver of biodiversity loss. To reduce these impacts, billions of dollars are spent on biodiversity offsets. However, studies evaluating offset project effectiveness that examine components such as the overall compliance and function of projects remain rare. We reviewed 577 offsetting projects in freshwater ecosystems that included the metrics project size, type of aquatic system (e.g., wetland and creek), offsetting measure (e.g., enhancement, restoration, and creation), and an assessment of the projects’ compliance and functional success. Project information was obtained from scientific and government databases and gray literature. Despite considerable investment in offsetting projects, crucial problems persisted. Although compliance and function were related to each other, a high level of compliance did not guarantee a high degree of function. However, large projects relative to area had better function than small projects. Function improved when projects targeted productivity or specific ecosystem features and when multiple complementary management targets were in place. Restorative measures were more likely to achieve targets than creating entirely new ecosystems. Altogether the relationships we found highlight specific ecological processes that may help improve offsetting outcomes.     

Some polyphagous Homoptera gain protection from their natural enemies by feeding on the toxic plantsSpartium junceum andErythrina corallodendrum (Leguminosae)

Summary Interactions were studied among alkaloid-containing legumes (Erythrina corallodendrum andSpartium junceum) and non-toxic plants (Citrus sinensis, Cucurbita moschata andEuphorbia tirucalli), several polyphagous homopterans,Aphis craccivora (Aphididae),Icerya purchasi, I. aegyptiaca (Margarodidae),Lepidosaphes ulmi (Diaspididae) andPlanococcus citri (Pseudococcidae), and some major natural enemies of these homopterans. Significant reductions in survival due to negative effects of alkaloid containing as compared with non-alkaloidal plants were recorded for the predatorsRodolia cardinalis andChilocorus bipustulatus, but not forCryptolaemus montrouzieri (Coleoptera: Coccinellidae),Chrysoperla carnea (Neuroptera: Chrysopidae) andSympherobius sanctus (Neuroptera: Sympherobiidae). The development time of the larvae or pupae ofR. cardinalis, C. carnea andS. sanctus was longer on the toxic plants than on the non-toxic ones. The percentage of parasitism ofA. craccivora collected from the non-alkaloidal plantsVicia palaestina andMelilotus albus was much higher than that onS. junceum. The parasitoid complexes ofA. craccivora differed between both plant groups. The nutritive value of honeydew ofI. purchasi andA. craccivora, as expressed by the life span ofEncyrtus infelix (Hymenoptera: Encyrtidae) adults, was also investigated. Life spans were significantly longer when the wasps fed on honeydew produced on non-alkaloidal plants (C. sinensis andPittosporum tobira) than on alkaloid containing plants whenI. purchasi — but notA. craccivora — was the producer. It is suggested that the chemical defense ofE. corallodendrum andS. junceum is exploited by polyphagous phytophages to reduce predation. In nature, population growth and density of four of the investigated homopterans are conspicuously high when they developed on the alkaloid containing plant species, and very low on non-alkaloid plants. The efficiency of their natural enemies may be reduced by sequestration of alkaloids (or other toxic plant compounds) or their transfer into excreted honeydew. Therefore it is assumed that a generalist phytophagous homopteran may be protected from its natural enemies, although at different rates of efficiency, if it can safely sequester the host allelochemical when it develops on toxic species within its host range.     

A palaeo-hydrogeological model for arsenic contamination in southern and south-east Asia

An argument is presented in which areas of natural arsenic contamination of modern groundwaters throughout Asia have a common origin. Arsenic originally accumulated in oceanic ferro-manganoan sediments of the eastern Palaeo-Tethys. This was further concentrated through oceanic crustal extinction in what later became the south-east Chinese accreted mineralised terrain. Proto-Himalayan uplift of this area created the palaeo-drainage systems of the Ganges – Brahmaputra, Irrawaddy, Mekong, and Red Rivers, with consequent headwater erosion of arsenic-rich sediments. Their downstream deposition as immature and easily redistributed Neogene sandstones, silts, and iron-rich clays has created secondary and tertiary reservoirs of adsorbed and authigenic arsenic, from which the current arsenic-rich groundwaters have evolved. Considering river basins within the above palaeo-hydrogeological framework provides a basis for assessing the risk of arsenic in groundwater basins of south and south-eastern Asia.     

Sequestration of cucurbitacin analogs by New and Old World chrysomelid leaf beetles in the tribe Luperini

Summary Two South American polyphagous leaf beetles,Diabrotica speciosa andCerotoma arcuata, selectively accumulated the bitter tasting compound 23,24-dihydrocucurbitacin D in their body after ingesting root tissues of cucurbit plants. Similarly, three Asian Cucurbitaceae-feeding specialists in the genusAulacophora were found to sequester the same compound. Cucurbitacin analogs were shown to deter feeding by a bird predator, indicating an allomonal role for these compounds in cucurbitacin-associated chrysomelid leaf beetles both of New and Old Worlds. The strong affinity to cucurbitacins, selective sequestration of the analogs and consequent protection from predators suggested an ecological adaptation mechanism developed in common among these two geographically isolated subtribes in the Luperini.     

Threats to intact tropical peatlands and opportunities for their conservation

Large, intact areas of tropical peatland are highly threatened at a global scale by the expansion of commercial agriculture and other forms of economic development. Conserving peatlands on a landscape scale, with their hydrology intact, is of international conservation importance to preserve their distinctive biodiversity and ecosystem services and maintain their resilience to future environmental change. We explored threats to and opportunities for conserving remaining intact tropical peatlands; thus, we excluded peatlands of Indonesia and Malaysia, where extensive deforestation, drainage, and conversion to plantations means conservation in this region can protect only small fragments of the original ecosystem. We focused on a case study, the Pastaza‐Marañón Foreland Basin (PMFB) in Peru, which is among the largest known intact tropical peatland landscapes in the world and is representative of peatland vulnerability. Maintenance of the hydrological conditions critical for carbon storage and ecosystem function of peatlands is, in the PMFB, primarily threatened by expansion of commercial agriculture linked to new transport infrastructure that is facilitating access to remote areas. There remain opportunities in the PMFB and elsewhere to develop alternative, more sustainable land‐use practices. Although some of the peatlands in the PMFB fall within existing legally protected areas, this protection does not include the most carbon‐dense (domed pole forest) areas. New carbon‐based conservation instruments (e.g., REDD+, Green Climate Fund), developing markets for sustainable peatland products, transferring land title to local communities, and expanding protected areas offer pathways to increased protection for intact tropical peatlands in Amazonia and elsewhere, such as those in New Guinea and Central Africa which remain, for the moment, broadly beyond the frontier of commercial development.     

Effects of Controlled Fire and Livestock Grazing on Bird Communities in East African Savannas

Abstract: In East Africa fire and grazing by wild and domestic ungulates maintain savannas, and pastoralists historically set fires and herded livestock through the use of temporary corrals called bomas. In recent decades traditional pastoral practices have declined, and this may be affecting biodiversity. We investigated the effects of prescribed fires and bomas on savanna bird communities in East Africa during the first and second dry seasons of the year (respectively before and after the rains that mark the onset of breeding for most birds). We compared abundance, richness, and community composition on 9‐ha burned plots, recently abandoned bomas, and control plots in the undisturbed matrix habitat over a 3‐year period. Generally, recently burned areas and abandoned bomas attracted greater densities of birds and had different community assemblages than the surrounding matrix. The effects of disturbances were influenced by interactions between primary productivity, represented by the normalized difference vegetation index, and time. Bird densities were highest and a greater proportion of species was observed on burned plots in the months following the fires. Drought conditions equalized bird densities across treatments within 1 year, and individuals from a greater proportion of species were more commonly observed on abandoned bomas. Yearly fluctuations in abundance were less pronounced on bomas than on burns, which indicate that although fire may benefit birds in the short term, bomas may have a more‐lasting positive effect and provide resources during droughts. Several Palearctic migrants were attracted to burned plots regardless of rainfall, which indicates continued fire suppression may threaten their already‐declining populations. Most notably, the paucity of birds observed on the controls suggests that the current structure of the matrix developed as a result of fire suppression. Traditional pastoralism appears critical to the maintenance of avian diversity in these savannas.     

Cost‐effective conservation of an endangered frog under uncertainty

How should managers choose among conservation options when resources are scarce and there is uncertainty regarding the effectiveness of actions? Well‐developed tools exist for prioritizing areas for one‐time and binary actions (e.g., protect vs. not protect), but methods for prioritizing incremental or ongoing actions (such as habitat creation and maintenance) remain uncommon. We devised an approach that combines metapopulation viability and cost‐effectiveness analyses to select among alternative conservation actions while accounting for uncertainty. In our study, cost‐effectiveness is the ratio between the benefit of an action and its economic cost, where benefit is the change in metapopulation viability. We applied the approach to the case of the endangered growling grass frog (Litoria raniformis), which is threatened by urban development. We extended a Bayesian model to predict metapopulation viability under 9 urbanization and management scenarios and incorporated the full probability distribution of possible outcomes for each scenario into the cost‐effectiveness analysis. This allowed us to discern between cost‐effective alternatives that were robust to uncertainty and those with a relatively high risk of failure. We found a relatively high risk of extinction following urbanization if the only action was reservation of core habitat; habitat creation actions performed better than enhancement actions; and cost‐effectiveness ranking changed depending on the consideration of uncertainty. Our results suggest that creation and maintenance of wetlands dedicated to L. raniformis is the only cost‐effective action likely to result in a sufficiently low risk of extinction. To our knowledge we are the first study to use Bayesian metapopulation viability analysis to explicitly incorporate parametric and demographic uncertainty into a cost‐effective evaluation of conservation actions. The approach offers guidance to decision makers aiming to achieve cost‐effective conservation under uncertainty.