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1.
几种裸子植物胚乳愈伤组织的诱导   总被引:4,自引:0,他引:4  
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%.  相似文献   

2.
以红江橙(CitrussinensisOsbeckcv.‘Hongjiang’)实生苗的根尖、下胚轴、子叶、上胚轴、茎段及叶片为材料进行培养,结果表明:上胚轴、茎段出芽率较高,分别为978%(45/46)及70.7%(29/41).ρ(MT+BA)1mg·L-1对上胚轴出芽效果较好,ρ(BA)升高,出芽率随之下降红江橙愈伤组织的诱导,其适宜的培养基为MT+2,4-D05+BA(KT)1(ρ/mg·L-1)NAA与BA(或ZT)结合有利于红江橙愈伤组织的分化,低浓度的BA效果较好些,随BA浓度升高,分化率下降红江橙不同外植体诱导的愈伤组织,分化能力也有差异,子叶愈伤组织更易分化,分化率可达357%(15/42);胚诱导的愈伤组织次之,其分化能力随着分化前培养时间的延长而下降无根苗诱导生根,其适宜的培养基ρ(MT+NAA)1mg·L-1.  相似文献   

3.
槐树组织培养中超度含水态苗发生与防止的研究   总被引:5,自引:0,他引:5  
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.  相似文献   

4.
紫羊茅(Festucarubra)抗铜品种Merlin和敏感品种559种子在水中吸胀5d后长出的幼苗在一般培养液中分别培养了0、2、4、6、8和10d(分别称为D0、D2、D4、D6、D8和D10)后再置于ρ(Cu2+)=5mg/L的相同培养液中,其中约一半培养至d20,其余至d27.结果与同龄的幼苗相比,MerlinD6在27d和20d的根中均有最高的干物质含量和最大的叶绿素浓度;在27d苗的根中铜积累了最少;而MerlinD6的苗在各个抗性处理组中最高在从20d至27d的培养期间,MerlinD6地上部分的干物质增加最多,而根中则减少最多,叶绿素含量也减少最多,在根中积累的铜也最少;可是在敏感的S59中则没有这种特殊现象,这些现象暗示,即使是在抗性品种的Merlin中,在其不同的生长时期经铜处理,也表现出不同的抗性,并可能有一个抗性最大的生长期。  相似文献   

5.
建立了香花槐组培苗快繁无性系.在改良MS培养基中添加ρ(6-BA)/mg L^-1=0.35~0.5、ρ(NAA)/mg L^-1=0.05~0.08,ρ(GA3)/mg L^-1=0.07~0.1作为生长培养基.在丛生芽诱导培养基中,ρ(6-BA)/mg L^-1=0.8~1.4,其余成分同生长培养基.两种培养方法同时使用,保证了组培苗繁殖系数为5左右.生根培养基中大量元素为MS基本培养基的1/4,ρ(IBA)/mg L^-1=0.1~0.5、ρ(IAA)/mg L^-1=1.7~2.5,香花槐组培苗的生根率为90%.炼苗后组培苗的移栽成活率为85%,且植株表型未见变异.将MS基本培养基中硝酸钾的含量由1.9g/L提高至2.199~2.931g/L,可满足每代香花槐试管苗生长25~35d期间对钾的需求.将培养基中6-BA的含量降至0.4mg/L,并采用合适的组培容器,在连续培养2、3代后,可将超度含水态苗的发生频率控制在10%以下,在6mo内生产100万株香花槐组培移栽苗.图1表1参16  相似文献   

6.
原生质体转化构建有机磷农药降解工程菌   总被引:5,自引:0,他引:5  
降解有机磷农药甲胺磷、敌敌畏和对硫磷的菌株地衣芽孢杆菌 P12( Bacilluslicheniformis) 经溶菌酶处理获得原生质体,加入降解乐果的供体菌 G1 D N A,经ρ( P E G6 000) = 300 g L- 1 诱导,在液体再生培养基中振荡培养t= 20 h ,使其恢复细胞壁后,离心收集菌体,涂布于含乐果的基础培养基上,经筛选得一转化子 J P Z.其菌落形态明显不同于出发菌株,乐果平板连续传代10 次,性状保持稳定.在θ= 30 ℃,100 r/min 的培养条件下,3 d 内对ρ( 甲胺磷) = 0 .5 g L- 1 ,ρ( 敌敌畏) = 0 .2 g L- 1 ,ρ( 对硫磷) = 0 .1 g L- 1 ,ρ( 乐果) = 0 .3 g L- 1 的降解率分别为 Rd = 79 .1 % ,46 .7 % ,29 .4 % 和46 .4 % .  相似文献   

7.
不同消毒剂对水中脊髓灰质炎病毒灭活的比较   总被引:4,自引:1,他引:3  
将脊髓灰质炎病毒( Polio V) 及不同消毒剂投加到模拟水样中,按不同接触时间1 ,3 ,10 ,30 min 取样,空斑定量. 当模拟水有机质含量 C O D 为20 mg/ L,病毒浓度n( P F U) ≈1 ×105 m L- 1 时,分别投加氯制剂有效氯ρ( Cl)16 mg/ L,接触30 min ;ρ( Cl O2) = 8 .0 mg/ L,30 min ; Cl+ Cl O2 联合消毒剂(5 .0 + 5 .0) mg/ L,30 min ;ρ( O3) = 1 .22 mg/ L,10 min 时;可使病毒彻底灭活. 它们使 Polio V 达到99 .99 % 灭活的浓度时间乘积( ρ×t) 值分别是662 .5 ,129 .5 ,200 .0 和3 .2 mg L- 1 min . 消毒效果( 顺序) 为 O3 > Cl O2 > Cl+ Cl O2 > Cl. 联合消毒灭活 Polio V 的效果为 Cl 的3 .3 倍,表明将 Cl 与 Cl O2 联合应用具有协同效应,优于传统的单一加氯消毒方式  相似文献   

8.
UASB反应器高温处理酒精废液的研究   总被引:7,自引:0,他引:7  
在θ=53±1℃条件下,采用UASB用1mo培养出颗粒污泥,到运行结束时,污泥ρ(TS)为65·0g·L-1,SVI为14.0,Umax(CH4)为603.9mL·g-1·d-1,对颗粒污泥微生物类群数量和微观结构的分析表明,颗粒污泥具有活性和结构上的高效性;反映在处理效果上,使UASB具有高效稳定的运行结果:当t(HRT)24.0~18.4h,容积负荷大于20g·L-1·d-1时,甲烷含量约60%,COD去除率约91%,出水ρ(COD)1400~2000mg·L-1,厌氧生物降解的产能和治污效果良好  相似文献   

9.
Cd^2+对玉米种子活力的影响及Ca^2+的拮抗作用   总被引:8,自引:0,他引:8  
用不同浓度(c)的Cd2+和Cd2++Ca2+处理玉米种子,以研究Cd2+对玉米种子活力的毒害及Ca2+对Cd2+的拮抗作用,结果表明:在0~0.5mmol/L的c(Cd2+)范围内,种子的发芽率、幼苗生长量随c(Cd2+)的增大而降低,Cd2+能降低玉米幼苗中超氧物歧化酶(SOD)和过氧化氢酶(CAT)的活性,并能增加膜脂过氧化产物丙二醛(MDA)的含量.用Cd2++Ca2+处理玉米种子时,Ca2+能减少以至消除Ca2+对种子活力和幼苗生长的毒害作用,其中c(Cd2+)为10mmol/L的拮抗作用明显大于5mmol/L.  相似文献   

10.
吸水链霉菌井冈变种JG5008转化系统的初建   总被引:3,自引:0,他引:3  
吸水链霉菌井冈变种JG5008的最佳转化条件是:JG5008在添加MgCl2(cf=0.005mol/L)和甘氨酸(ρf=0.5g/L)的含10%蔗糖的YEME培养基中接种浓度n≈10^8mL^-1的JG5008孢子悬液,37℃摇床培养12h,收获菌丝体。在32℃、溶菌酶浓度ρ=2mg/mL的条件下溶菌1h后制备原生质体,用T缓冲液在R2YE培养基上进行转化。本文初步建立了JG5008的质粒载体系  相似文献   

11.
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  相似文献   

12.
Protected areas (PAs) are often implemented without consideration of already existing PAs, which is likely to cause an overrepresentation of certain biophysical conditions. We assessed the representativeness of the current PA network with regard to the world's biophysical conditions to highlight which conditions are underprotected and where these conditions are located. We overlaid terrestrial and marine PAs with information on biophysical conditions (e.g., temperature, precipitation, and elevation) and then quantified the percentage of area covered by the PA network. For 1 variable at a time in the terrestrial realm, high temperature, low precipitation, and medium and very high elevation were underrepresented. For the marine realm, low and medium sea surface temperature (SST), medium and high sea surface salinity (SSS), and the deep sea were underrepresented. Overall, protection was evenly distributed for elevation across the terrestrial realm and SST across the marine realm. For 2 variables at a time, cold and very dry terrestrial environments had mostly low protection, which was also the case for low SST and low and medium SSS across most depths for marine environments. Low protection occurred mostly in the Sahara and the Arabian Peninsula for the terrestrial realm and along the Tropic of Capricorn and toward the poles for the marine realm. Although biodiversity measures are of prime importance for the design of PA networks, highlighting biophysical gaps in current PAs adds a frequently overlooked perspective. These gaps may weaken the potential of PAs to conserve biodiversity. Thus, our results may provide useful insights for researchers, practitioners, and policy makers to establish a more comprehensive global PA network.  相似文献   

13.
Summary The adaptation of defensive secretions to their target organisms was examined for the abdominal gland secretions ofBledius furcatus, B. spectabilis andB. arenarius. Therefore the target organisms of the secretion of theseBledius species (i.e. their predators) had to be identified. At the collection sites examined these were the earwigLabidura riparia, the antCataglyphis bicolor, the flyLispe candicans, different carabids of the generaPogonus, Dichirotrichus, Dyschirius, Bembidion andCalathus and the wading birdsHaematopus ostralegus andCalidris alba. The secretion of the abdominal glands contains the toxin ptoluquinone dissolved in either-dodecalactone and 1-undecene (B. furcatus andB. spectabilis) or in octanoic acid and octyloctanoate (B. arenarius). The ratio of these solvents is species-specific. Application experiments using some of the natural insect predators (L. riparia, C. bicolor, Pogonus, Di. gustavii, Dyschirius) revealed that these solvent ratios provided a more effective deterrent than other possible ratios. Thus by combining the solvents in certain ratios, the capability of cuticular penetration and therefore the effectiveness of the defensive secretions are adapted to their natural targets.  相似文献   

14.
The politics of development includes subtexts of choice, as underpinned by community consensus (or lack of it), against the larger backdrop of a liberal democracy, with its intricate power structures that influence the choice of concepts and often lead to complicity rather than consent. A dilemma exists between the understanding of field-level practitioners and that of academics, whose understandings of progress differ. Progress can (and often does) imply long-term change across generations whereas development is often more a matter of crisis management and delivering tangible results to end-users. This makes it a bone of contention across political systems, irrespective of local or global dynamics. Development can emerge as a tool to be wielded for power and further political mileage at the expense of progress. Progress cannot be studied as a counterpoint to development as the sense of history is often missing in development interventions. Development tends to be piecemeal as its very logic often stems from the rationale of power. This is not to suggest, however, that development is only about politics; it is definitely more than the politics of everyday life and involves all of civil society that requires its critical and immediate attention. In this sense, it has become a priority for politicians with an underlying agenda designed to out-manouevre dissent and all statements of protest.  相似文献   

15.
As landscapes continue to fall under human influence through habitat loss and fragmentation, fencing is increasingly being used to mitigate anthropogenic threats and enhance the commercial value of wildlife. Subsequent intensification of management potentially erodes wildness by disembodying populations from landscape-level processes, thereby disconnecting species from natural selection. Tools are needed to measure the degree to which populations of large vertebrate species in formally protected and privately owned wildlife areas are self-sustaining and free to adapt. We devised a framework to measure such wildness based on 6 attributes relating to the evolutionary and ecological dynamics of vertebrates (space, disease and parasite resistance, exposure to predation, exposure to limitations and fluctuations of food and water supply, and reproduction). For each attribute, we set empirical, species-specific thresholds between 5 wildness states based on quantifiable management interventions. We analysed data from 205 private wildlife properties with management objectives spanning ecotourism to consumptive utilization to test the framework on 6 herbivore species representing a range of conservation statuses and commercial values. Wildness scores among species differed significantly, and the proportion of populations identified as wild ranged from 12% to 84%, which indicates the tool detected site-scale differences both among populations of different species and populations of the same species under different management regimes. By quantifying wildness, this framework provides practitioners with standardized measurement units that link biodiversity with the sustainable use of wildlife. Applications include informing species management plans at local scales; standardizing the inclusion of managed populations in red-list assessments; and providing a platform for certification and regulation of wildlife-based economies. Applying this framework may help embed wildness as a normative value in policy and mitigate the shifting baseline of what it means to truly conserve a species.  相似文献   

16.
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.  相似文献   

17.
Abstract: In the United States, as elsewhere, a growing debate pits national energy policy and homeland security against biological conservation. In rural communities the extraction of fossil fuels is often encouraged because of the employment opportunities it offers, although the concomitant itinerant workforce is often associated with increased wildlife poaching. We explored possible positive and negative factors associated with energy extraction in the Greater Yellowstone Ecosystem (GYE), an area known for its national parks, intact biological diversity, and some of the New World's longest terrestrial migrations. Specifically, we asked whether counties with different economies—recreation (ski), agrarian (ranching or farming), and energy extractive (petroleum)—differed in healthcare (gauged by the abundance of hospital beds) and in the frequency of sexual predators. The absolute and relative frequency of registered sex offenders grew approximately two to three times faster in areas reliant on energy extraction. Healthcare among counties did not differ. The strong conflation of community dishevel, as reflected by in‐migrant sexual predators, and ecological decay in Greater Yellowstone is consistent with patterns seen in similar systems from Ecuador to northern Canada, where social and environmental disarray exist around energy boomtowns. In our case, that groups (albeit with different aims) mobilized campaigns to help maintain the quality of rural livelihoods by protecting open space is a positive sign that conservation can matter, especially in the face of rampant and poorly executed energy extraction projects. Our findings further suggest that the public and industry need stronger regulatory action to instill greater vigilance when and where social factors and land conversion impact biological systems.  相似文献   

18.
Summary Acanthoscelides obtectus (Say) is one of the most damaging pests of kidney beans,Phaseolus vulgaris L. worldwide. However, aromatic plants from the families Lamiaceae, Lauraceae, Myrtaceae and Poaceae can protect kidney beans by direct or delayed insecticidal effect, through increased adult mortality and inhibition of beetle reproduction (both oviposition and adult emergence). The efficiency of hydrodistillated and intact plants fromThymus vulgaris andT. serpyllum, Mentha piperata, Rosmarinus officinalis, Satureia hortensis, Eucalyptus globulus, Laurus nobilis, Origanum vulgare, andCymbopogon nardus was compared. For both extracts,Origanum vulgare had the best effect. The insecticidal effect was induced by more than the essential oils because no significant difference was noticed between distilled and intact plants extract. Inhibition of reproduction was particularly important. These results suggest that lipidic as well as non lipidic, allelochemicals, such as phenolics, or non-protein amino-acids, or flavonoids may be involved in the toxicity of aromatic plants to this beetle.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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