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1.
为了合理利用和保护天敌进行卵形短须螨、双斑长跗萤叶甲和假眼小绿叶蝉的综合防治,用灰色系统分析方法和生态位分析法对合肥地区白毫早茶园3种主要害虫与其捕食性天敌在数量、时间、空间等方面关系进行分析,利用害虫与天敌关系密切指数之和综合评判9种天敌与3种害虫关系密切的前四位天敌。2015年卵形短须螨的前四位天敌是鳞纹肖蛸(5.3079)、三突花蟹蛛(5.1716)、锥腹肖蛸(4.8367)和草间小黑蛛(4.7869);2016年前四位天敌依次是三突花蟹蛛(5.3975)、鳞纹肖蛸(4.9414)、茶色新圆蛛(4.8757)、锥腹肖蛸(4.6815)。对两年结果综合分析,卵形短须螨的前四位天敌依次是三突花蟹蛛(10.5691)、鳞纹肖蛸(10.2493)、茶色新圆蛛(9.6353)和锥腹肖蛸(9.5182)。2015年双斑长跗萤叶甲的前四位天敌依次是锥腹肖蛸(5.6926)、异色瓢虫(5.6976)、八斑球腹蛛(5.5101)和斜纹猫蛛(5.4552);2016年依次是茶色新圆蛛(5.2909)、锥腹肖蛸(5.2710)、鳞纹肖蛸(5.1063)和斜纹猫蛛(5.0703)。对两年结果综合评判,双...  相似文献   

2.
中国苦苣苔科植物的多样性与地理分布(附表)   总被引:2,自引:0,他引:2  
许为斌  郭婧  盘波  张强  刘演 《广西植物》2017,37(10):1226-1226
物种多样性编目是开展生物多样性保护的重要基础,该研究结合最新分子系统学研究成果以及近年来发表的新资料,对中国苦苣苔科植物多样性和地理分布数据进行了统计和分析.结果表明:中国苦苣苔科植物共有44属671种(含种下单位,下同),其中特有属11个;特有种573种,占总种数的85.39%.种数最多的10个属依次为广义报春苣苔属(180种)、广义马铃苣苔属(122种)、石蝴蝶属(39种)、半蒴苣苔属(39种)、芒毛苣苔属(38种)、长蒴苣苔属(35种)、石山苣苔属(31种)、吊石苣苔属(31种)、蛛毛苣苔属(28种)、汉克苣苔属(22种).在地理分布上,种数排名前10的省份(区)有广西(260种,33属)、云南(236种,30属)、贵州(96种,28属)、广东(93种,17属)、四川(85种,21属)、湖南(58种,13属)、西藏(39种,9属)、湖北(29种,15属)、福建(26种,13属)、江西(25种,9属).含中国特有苦苣苔科植物的属中排前10位的分别为广义报春苣苔属(178种)、广义马铃苣苔属(119种)、石蝴蝶属(37种)、半蒴苣苔属(35种)、石山苣苔属(30种)、长蒴苣苔属(29种)、吊石苣苔属(23种)、蛛毛苣苔属(19种)、芒毛苣苔属(19种)、汉克苣苔属(11种).这表明中国南部和西南部是苦苣苔科植物的一个分布中心,特别是石灰岩地区有着高度的物种多样性和特有性,广义报春苣苔属、广义马铃苣苔属、石蝴蝶属、半蒴苣苔属、石山苣苔属、吊石苣苔属等为我国典型的优势属.此外,根据目前的研究现状,还对我国苦苣苔科植物资源的调查、分类学和系统发育研究、保护和可持续利用等进行了讨论.  相似文献   

3.
Vigo is a city located in the northwest of the Iberian Peninsula. Influenced by the Atlantic climate, it is surrounded by a Eurosiberian-type vegetation, modified by the introduction of forestry and ornamental species. Different ruderal vegetation types, resulting from human influence, grow in the area. The study of the pollen content of the air of Vigo started in 1989, with a Cour trap. Average results for the period 1989–1995 are presented in this paper, together with the lowest and highest values found. The representativeness of the mean values is analysed by calculating the coefficient of variation of the data series. Most pollen types in the atmosphere of Vigo are from tree species (54.2%); an important proportion comes from herb species (43.9%) and very few (1.8%) correspond to shrub species. A total of 73 different pollen types have been identified. The most abundant, listed in decreasing order of mean annual values for the period, are:Pinus (25.1%), Poaceae (21.1%), Urticaceae (14.6%),Quercus (8.5%),Castanea (3.7%),Betula (3.6%),Eucalyptus (3.4%),Plantago (3.2%),Alnus (2.1%), Cupressaceae (2.1%), Oleaceae (1.6%;Olea 1.3%),Platanus (1.3%),Rumex (1.3%), Chenopodiaceae/Amaranthaceae (1.0%), Ericaceae (0.8%), Asteraceae (0.6%;Artemisia 0.1% andTaraxacum type 0.2%) andMercurialis (0.5%). A pollen calendar showing the annual dynamics of all these pollen types is presented in this paper. A parallel study of the clinical importance of respiratory allergies in Vigo was also conducted. From a sample of 2750 patients, 87.2% suffered from rhinoconjunctivitis, 26.0% of these due to pollen, and 78.3% from asthma, 17.2% due to pollen. The pollen types responsible for these allergies, listed in decreasing order, are: Poaceae (78%),Parietaria (12%),Chenopodium (11%),Plantago (9%), Oak (4%),Artemisia (3%),Pinus (3%),Eucalyptus (3%),Olea (2%),Platanus (2%),Castanea (2%),Taraxacum (2%),Rumex (2%),Betula (1%),Cupressus (1%) andMercurialis (1%).  相似文献   

4.
A total of 25 items are listed. 16 are new taxa described from South and East Anatolia:Papaver (1),Heldreichia (1),Astragalus (1),Lotus (1),Onobrychis (3),Sempervivum (2),Hellenocarum (1),Cirsium (2),Campanula (1),Omphalodes (1),Allium (1) andPuccinellia (1). Nine other species belonging to the generaDiplotaxis, Beta, Acacia, Lupinus, Cirsium, Limonium, Calamagrostis andPuccinellia, are new records for the Flora of Turkey area. Two combinations are made, one inPapaver (p. 113), the other inHellenocarum (p. 122).  相似文献   

5.
Mesophilic heterotrophic, aerobic or facultatively anaerobic bacteria that grow on yeast tryptone glucose extract agar were isolated from the surface of olive leaves of 3 or 4 different ages in January, April, July, and October from 1984 to 1989. Unweighted average linkage cluster analysis on either the Jaccard coefficient or the simple matching coefficient recovered 1,701 representative strains in 32 phena defined at the 70% and 80% similarity level, respectively. Of these, 25 were identified to genus or lower level. From the identity of the representative strains, the frequency of occurrence among the phylloplane bacteria over the 6-year period was estimated at 51% forPseudomonas syringae, followed byXanthomonas campestris (6.7%),Erwinia herbicola (6%),Acetobacter aceti (4.7%),Gluconobacter oxydans (4.3%),Pseudomonas fluorescens (3.9%),Bacillus megaterium (3.8%),Leuconostoc mesenteroides subsp.dextranicum (3.1%),Lactobacillus plantarum (2.8%),Curtobacterium plantarum (2.2%),Micrococcus luteus (2.2%),Arthrobacter globiformis (1.4%),Klebsiella planticola (1.2%),Streptococcus faecium (1.2%),Clavibacter sp. (0.98%),Micrococcus sp. (0.82%),Serratia marcescens (0.81%),Bacillus subtilis (0.57%),Cellulomonas flavigena (0.4%),Erwinia sp. (0.37%),Zymomonas mobilis (0.3%),Bacillus sp. (0.29%),Alcaligenes faecalis (0.27%),Erwinia carotovora (0.08%), andPseudomonas aeruginosa (0.04%). Bacterial communities on leaves of a given age at a given time during any one year displayed a very similar structure but differed significantly from those on the leaves of the same age at a different time or on the leaves of a different age at any time during any one year. Communities on the leaves of a given age at a given time of the year were invariably dominated by one or another of only 9 taxa, which accounted for 22 to 98.5% of the isolates from those leaves. The communities on 10- and 13-month-old leaves were invariably made up of fewer taxa than those on younger leaves at the same time of the year.  相似文献   

6.
Phlebotomine sand flies (Diptera: Psychodidae, Phlebotominae) are of considerable public health importance because of their ability to transmit several human parasites, mainly as vectors of Leishmania spp. Over the past decade, the epidemiological situation of cutaneous leishmaniasis (CL) has significantly increased with its geographic expansion to previously free areas and the emergence of overlapping foci of cutaneous leishmaniasis and visceral leishmaniasis (VL) in several provinces of Morocco. A total of 15,313 specimens was collected during this entomological survey. The genera Phlebotomus (57.38%) and Sergentomyia (42.62%) were identified. Sergentomyia minuta (22.01%) was the most prevalent species, followed by S. fallax (18.21%), Phlebotomus perniciosus (14.35%), P. papatasi (14.06%), P. sergenti (12.85%), P. longicuspis (10.74%), P. ariasi (2.68%), S. dreyfussi (1.53%), P. alexandri (1.31%), P. bergeroti (1.14%), S. christophersi (0.62%), S. africana (0.25%), P. chabaudi (0.14%), P. chadlii (0.05%), and P. kazeruni (0.04%). We aimed to determine current distribution of leishmaniases vectors, their ecological characteristics, and the significance of the predominant species at any bioclimate stage, altitude range, and soil texture in terms of the risk of leishmaniasis transmission.  相似文献   

7.
Species diversity and abundance of small mammals were studied in Nechisar National Park, Ethiopia, during August 2008 – March 2009. Twenty species of rodents and four species of insectivores were recorded from the study area. Mastomys natalensis (17.37%), Arvicanthis dembeensis (17.09%), Mastomys erythroleucus (8.90%), Stenocephalemys albipes (8.76%), Arvicanthis niloticus (8.19%), Acomys cahirinus (7.34%), Lemniscomys striatus (6.92%), Gerbilliscus nigricauda (6.21%), Grammomys dolichurus (3.67%), Gerbilliscus robusta (2.12%), Mus proconodon (1.98%), Mus mahomet (1.41), Dendromus melanotis (1.27%), Arvicanthis abyssinicus (1.13%), Mus musculus (0.99%), Praomys fumatus (0.85%), Xerus erythropus (0.85%), Lemniscomys barbarus (0.71%), Mus tenellus (0.71%) and Otomys typus (0.28%) were the rodents and their respective relative abundance in the study area. Crocidura olivieri (1.55%), Crocidura fumosa (0.85%), Crocidura bicolor (0.57%) and Elephantulus rufescens (0.28%) were the insectivores recorded with their respective relative abundance. Mastomys natalensis was the most abundant and O. typus and E. rufescens were the least (two each). Diversity of small mammals ranged from 2.299 to 2.625 with an average of 2.412. The highest small mammal diversity was in grasslands and the lowest was in Lake Chamo shore. Small mammal density varied from 5 to 43 ha?1 and biomass varied from 244 to 2559 g ha?1 with significant changes in relation to seasons and habitats.  相似文献   

8.
Nineteen holotype specimens of the genus Torrubiella described by Dr. Yosio Kobayasi and Mr. Daisuke Shimizu were relocated and accession numbers (TNS-F number) were given. A new scientific name, Torrubiella plana Hiroki Sato, Ban, Masuya & Hosoya nom. nov. (TNS-F-12061), was proposed for T. minutissima Kobaysi & Shimizu (homonym of T. minutissima Lagarde). The other 18 species follow: T. alboglobosa (TNS-F-12067), T. aurantia (TNS-F-12069), T. corniformis (TNS-F-12064), T. ellipsoidea (TNS-F-12055), T. formosana (TNS-F-12059), T. fusiformis (TNS-F-234548), T. globosostipitata (TNS-F-12057), T. longissima (TNS-F-12071), T. mammillata (TNS-F-12060), T. miyagiana (TNS-F-12062), T. neofusiformis (TNS-F-12058), T. oblonga (TNS-F-12070), T. ooaniensis (TNS-F-12063), T. pallida (TNS-F-12789), T. rosea (TNS-F-12065), T. ryogamimontana (TNS-F-12058), T. ryukyuensis (TNS-F-11932), and T. superficialis (TNS-F-12072).  相似文献   

9.
Seven citrus orchards on reduced- to no-pesticide spray programs were sampled for predacious mites in the family Phytoseiidae (Acari: Mesostigmata) in central and south central Florida. Inner and outer canopy leaves, open flowers, fruit, twigs, and trunk scrapings were sampled monthly between September 1994 and January 1996. Vines and ground cover plants were sampled monthly between September 1994 and January 1996 in five of these orchards. The two remaining orchards were on full herbicide programs and ground cover plants were absent. Thirty-three species of phytoseiid mites were identified from 35,405 specimens collected within citrus tree canopies within the seven citrus orchards, and 8,779 specimens from vines and ground cover plants within five of the seven orchards. The six most abundant phytoseiid species found within citrus tree canopies were: Euseius mesembrinus (Dean) (20,948), Typhlodromalus peregrinus (Muma) (8,628), Iphiseiodes quadripilis (Banks) (2,632), Typhlodromips dentilis (De Leon) (592), Typhlodromina subtropica Muma and Denmark (519), and Galendromus helveolus (Chant) (315). The six most abundant species found on vines or ground cover plants were: T. peregrinus (6,608), E. mesembrinus (788), T. dentilis (451), I. quadripilis (203), T. subtropica (90), and Proprioseiopsis asetus (Chant) (48). The remaining phytoseiids included: Amblyseius aerialis (Muma), A. herbicolus (Chant), A. largoensis (Chant), A. multidentatus (Chant), A. sp. near multidentatus, A. obtusus (Koch), Chelaseius vicinus (Muma), Euseius hibisci Chant, Galendromus gratus (Chant), Metaseiulus mcgregori (Chant), Neoseiulus mumai (Denmark), N. vagus (Denmark), Phytoscutus sexpilis (Muma), Phytoseiulus macropilis (Banks), Proprioseiopsis detritus (Muma), P. dorsatus (Muma), P. macrosetae (Banks), P. rotundus (Muma), P. solens (De Leon), Typhlodromips deleoni (Muma), T. dillus (De Leon), T. dimidiatus (De Leon), T. mastus Denmark and Muma, T. simplicissimus (De Leon), and T. sp. near tunus, and Typhlodromus transvaalensis (Nesbitt). Eighty-two ground cover plants or vines were sampled within the five orchards and one or more phytoseiids were collected from 71 of these plants. Five ground cover plants with the highest numbers of phytoseiids included: Bidens alba (L.) DC (1,420 mites within 13 species), Solanum americanum L. (1,355 mites within 8 species), Amaranthus spinosus L. (1,137 mites within 11 species), Gnaphalium pensylvanicum Willd. (844 mites within 8 species) and Richardia brasiliensis (Meg.) Gomez (354 mites within 8 species).  相似文献   

10.
The pine processionary moth Thaumetopoea pityocampa (Den. and Schiff.) is one of the most harmful insect pest for pine species in Mediterranean countries including Turkey. The objective of the present study is to find a more effective and safe biological control agent against T. pityocampa. Thus, we investigated the bacterial flora of the pest insect, collected from the Middle Black Sea Region of Turkey from 2003 to 2004. Based on morphological, physiological, biochemical and molecular methods, 14 different bacterial isolates were determined. The identified bacterial flora of T. pityocampa consisted of bacteria belonging to the Enterobacteriaceae (Tp1), Arthrobacter sp. (Tp2), Staphylococcus spp. (Tp3 and 10), Bacillus subtilis (Tp4), Serratia liquefaciens (Tp5), Bacillus thuringiensis subsp. morrisoni (Tp6 and 14), an acrystalliferous form Bacillus thuringiensis (Tp7), Staphylococcus cohnii (Tp8), Bacillus licheniformis (Tp9), Bacillus pumilus (Tp11), Brevibacterium sp. (Tp12) and Bacillus simplex (Tp13). After analysing the conclusions of conventional and molecular tests Tp1 (Enterobacteriaceae), Tp2 (Arthrobacter sp.) and Tp12 (Brevibacterium sp.) were assigned as novel bacterial species. Isolate Tp5 had a promising insecticidal effect on third instar larvae of T. pityocampa (up to 70% mortality within 10 days).  相似文献   

11.
Preussia sp. have been least known to improve plant growth and produce phytohormones. The current study investigated the production of nitric oxide (NO), indole-3-acetic acid (IAA), and gibberellins (GA4, GA7, GA15, and GA53) by a novel endophytic-fungal strain Preussia sp. BSL-10 using advanced chromatographic and spectroscopic techniques. Production of these phytohormones were validated by RT–PCR analysis, which indicated the expression of genes encoding tryptophan synthase (TRP), indole-3-acetamide hydrolase (IAAH), tryptophan-2-monooxygenase (IAAM), aldehyde dehydrogenase (ALD), GA4 desaturase (DES), geranylgeranyl-diphosphate synthase (GGS2), ent-desaturase oxidase (P450-4), GA14 synthase (P450-1) and nitrite reductase (NIRK/NIRS), cytochrome P450 (P450nor), nitrate reductase (NR), NOS-like (NOL), and nitric oxide reductase (QNOR/CNOR). In plant growth-promoting effects, the inoculation of Preussia sp. BSL-10 significantly increased the growth of dwarf mutant Waito-C and wild-type rice cultivars. In conclusion, utilizing new endophytic with the ability to produce NO, IAA, and gibberellins can be used to promote growth and yield of marginalized crops.  相似文献   

12.
The occurrence of mycotic agents was investigated by hair-brush technique on the coat of 162 naturalized coypus (Myocastor coypus) and 64 indigenous brown rats (Rattus norvegicus) originating from the same protected area in Central Italy. The isolates from positive coypus (29.6%) were identified as Microsporum gypseum (14.8%), Trichophyton terrestre (9.8%), Alternaria sp. (3.7%), Trichophyton mentagrophytes (2.5%), Cladosporium sp. (1.8%), Scopulariopsis sp. (1.2%), and Chrysosporium keratinophilum (0.6%), whereas the isolates from positive rats (46.7%) were identified as M. gypseum (28.1%), T. mentagrophytes (12.5%), Chrysosporium tropicum and T. terrestre (3.1% each), and Chrysosporium inops (1.6%). Statistically, brown rats were more likely to harbor fungal agents (P < 0.05) on their coat than coypus, especially T. mentagrophytes (P < 0.01) and M. gypseum (P < 0.05). No positive animal showed dermatological lesions. The present results are the first providing basic information on the coat’s mycoflora of a wild coypu population. It is concluded that the coypu, an allochthonous rodent in Italy, can play a role as natural animal reservoir of dermatophytes and as carrier of keratinophilic and saprophytic fungi within its new habitat, though to a lesser extent than indigenous rats. Therefore, people who are exposed to the risk of contact with the coat of rats and coypus should take all the cautions needed to protect themselves from mycotic agents potentially transmissible to humans.  相似文献   

13.
Bioassay‐guided fractionation of the active AcOEt‐soluble layer led to the isolation of two new pyranocoumarins, 3‐hydroxyxanthyletin ( 1 ) and 3‐methoxyxanthyletin ( 2 ), along with 22 known compounds including four simple coumarins, i.e., xanthyletin ( 3 ), umbelliferone ( 4 ), scopoletin ( 5 ), and (+)‐(S)‐marmesin ( 6 ); nine flavonoids, i.e., carpachromene ( 7 ), parvisoflavone B ( 8 ), alpinumisoflavone ( 9 ) genistein ( 10 ), 2′‐hydroxygenistein ( 11 ), prunetin ( 12 ), cajanin ( 13 ), apigenin ( 14 ), and (2S)‐naringenin ( 15 ); three benzenoids, i.e., 4‐hydroxybenzaldehyde ( 16 ), vanillin ( 17 ), and (S)‐lasiodiplodin ( 18 ); five steroids, i.e., ergosterol peroxide ( 19 ), a mixture of 6β‐hydroxystigmast‐4‐en‐3‐one ( 20 ) and 6β‐hydroxystigmasta‐4,22‐dien‐3‐one ( 21 ), and a mixture of β‐sitosterol ( 22 ) and stigmasterol ( 23 ); and one triterpenoid, i.e., oleanolic acid ( 24 ) from the roots of Ficus nervosa. Their structures were elucidated on the basis of extensive 1D‐ and 2D‐NMR as well as MS analyses. Among these isolates, 3‐hydroxyxanthyletin ( 1 ), genistein ( 10 ), prunetin ( 12 ), and (2S)‐naringenin ( 15 ) showed antimycobacterial activities against Mycobacterium tuberculosis H37RV in vitro with MIC values of 16, 35, 30, and ≤2.8 μg/ml, respectively.  相似文献   

14.
The clock gene machinery controls cellular metabolism, proliferation, and key functions, such as DNA damage recognition and repair. Dysfunction of the circadian clock is involved in tumorigenesis, and altered expression of some clock genes has been found in cancer patients. The aim of this study was to evaluate the expression levels of core clock genes in colorectal cancer (CRC). Quantitative real-time polymerase chain reaction (qPCR) was used to examine ARNTL1, CLOCK, PER1, PER2, PER3, CRY1, CRY2, Timeless (TIM), TIPIN, and CSNK1Ε expression levels in the tumor tissue and matched apparently healthy mucosa of CRC patients. In the tumor tissue of CRC patients, compared to their matched healthy mucosa, expression levels of ARNTL1 (p?=?.002), PER1 (p?=?.002), PER2 (p?=?.011), PER3 (p?=?.003), and CRY2 (p?=?.012) were lower, whereas the expression level of TIM (p?=?.044) was higher. No significant difference was observed in the expression levels of CLOCK (p?=?.778), CRY1 (p?=?.600), CSNK1Ε (p?=?.903), and TIPIN (p?=?.136). As to the clinical and pathological features, a significant association was found between low CRY1 expression levels in tumor mucosa and age (p?=?.026), and female sex (p?=?.005), whereas high CRY1 expression levels in tumor mucosa were associated with cancer location in the distal colon (p?=?.015). Moreover, high TIM mRNA levels in the tumor mucosa were prevalent whenever proximal lymph nodes were involved (p?= .013) and associated with TNM stages III–IV (p?=?.005) and microsatellite instability (p?=?.015). Significantly poorer survival rates were evidenced for CRC patients with lower expression in the tumor tissue of PER1 (p?=?.010), PER3 (p?= .010), and CSNKIE (p?=?.024). In conclusion, abnormal expression levels of core clock genes in CRC tissue may be related to the process of tumorigenesis and exert an influence on host/tumor interactions. (Author correspondence: )  相似文献   

15.
In the current study, 18 salt-tolerant bacteria were isolated from salt-affected soil of Erzurum, Turkey. Forty-five bacterial isolates were identified and characterized by conventional and molecular techniques. These 45 sequenced isolates were identified as 16 different genus including Bacillus (19 isolates), Staphylococcus (3 isolates), Halobacillus (4 isolates), Zhihengliuella (2 isolates), Oceanobacillus (2 isolates), Halomonas (1 isolate), Nesterenkonia (2 isolates), Promicromonospora (2 isolates), Jeotgalibacillus (2 isolates), Planococcus (2 isolates), Virgibacillus (1 isolate), Terribacillus (1 isolate), Thalassobacillus (1 isolate), Marinibacillus (1 isolate), Gracilibacillus (1 isolate) and Microbacterium (1 isolate). According to the results obtained, investigated bacterial strains have high salt tolerance and significant enzyme activities that can improve soil nutrient cycling and soil fertility. The current article provides the evaluation and diversity of the potential halotolerant and halophilic bacterial strains in salt-affected soils of Erzurum, Turkey.  相似文献   

16.
In our screening program for new agrochemicals from local wild plants, Artemisia lavandulaefolia and A. sieversiana were found to possess insecticidal activity against the maize weevil Sitophilus zeamais. The essential oils of the aerial parts of the two plants were obtained by hydrodistillation and analyzed by GC and GC/MS. The main components of A. lavandulaefolia oil were caryophyllene (15.5%), β‐thujone (13.8%), eucalyptol (13.1%), and β‐farnesene (12.3%), and the principal compounds identified in A. sieversiana oil were eucalyptol (9.2%), geranyl butyrate (9.2%), borneol (7.9%), and camphor (7.9%). The essential oils of A. lavandulaefolia and A. sieversiana possessed fumigant toxicity against S. zeamais adults with LC50 values of 11.2 and 15.0 mg/l air, respectively. Both essential oils also showed contact toxicity against S. zeamais adults with LD50 values of 55.2 and 112.7 μg/adult, respectively.  相似文献   

17.
Lack of seed dispersal can be an important obstacle to natural regeneration (NR) of degraded pastures in the humid tropics. Tree plantations can facilitate secondary forest succession by attracting seed dispersal agents from nearby forests. We studied seed rain and seed dispersal agents in 12–13 years old pure and mixed native tree plantations at La Selva Biological Station, Costa Rica from July to December 2004. Plantations of Balizia elegans (5,522), Dipteryx panamensis (2,263), and Jacaranda copaia (2,091) had the greatest total seed abundance; treatments with the least total seed abundance were Calophyllum brasiliense (56), nonplanted abandoned pasture control 2 (353), Mixed Species 2 (389), and control 1 (836). Plantations of J. copaia and Hyeronima alchorneoides had the greatest seed species richness density, whereas the lowest seed species richness was found in the control treatments. The NR plots had more seeds dispersed by wind, whereas in the plantations, the most important dispersal agents were birds and mammals. The most abundant seeds were those of Miconia spp. (14,492), Psychotria bracheata (2,252), and the Poaceae family (1,346), all species from early successional stages. Plantations of native species are effective in attracting seed dispersal agents and thus facilitating regeneration of degraded pasturelands in the region.  相似文献   

18.
Wild killer yeasts have been identified as inhibitory to strains used as starters in the production of alcoholic beverages such as beer and wine; therefore, killer or killer-resistant strains have been sought for use in alcoholic fermentations. In the current paper a total of 16 strains belonging to six species were isolated. From two samples of Agave sap (aguamiel) the following yeast strains were isolated: Candida lusitaneae (1), Kluyveromyces marxianus var. bulgaricus (2), and Saccharomyces cerevisiae (capensis) (1). Additionally, in seven samples of pulque (the fermented product), the species C. valida (six strains), S. cerevisiae (chevalieri) (4), S. cerevisiae (capensis) (1), and K. marxianus var. lactis (1) were found. The killer strains were C. valida and K. marxianus var. lactis from pulque and K. marxianus var. bulgaricus from aguamiel. One strain of S. cerevisiae (chevalieri) isolated from pulque which did not show killer activity was, on the other hand, resistant to other killer strains and it had a remarkable ethanol tolerance, suggesting that this strain could be used for alcohol production.  相似文献   

19.
A phytochemical investigation of the roots of Chloranthus anhuiensis afforded three new sesquiterpene lactones, chloraniolide A ( 1 ), (3R)‐3‐hydroxyatractylenolide III ( 2 ), and 8β‐hydroxy‐1‐oxoeudesma‐3,7(11)‐dien‐12,8α‐olide ( 3 ), and two new diterpenoids, (12R,13E)‐15‐(acetoxy)‐12‐hydroxylabda‐8(20),13‐dien‐19‐oic acid ( 4 ) and (12S,13E)‐15‐(acetoxy)‐12‐dihydroxylabda‐8(20),13‐dien‐19‐oic acid ( 5 ), as well as 17 known sesquiterpenoid and diterpenoid compounds. Their structures were established on the basis of 1D‐ and 2D‐NMR, and other spectroscopic analyses.  相似文献   

20.
Five new and seven known mono‐sesquiterpenoids ( 1 – 5 and 6 – 12 , resp.) together with five known lindenane‐type disesquiterpenoids, 13 – 17 , were isolated from the whole plant of Chloranthus henryi. Based on spectroscopic methods, the new structures were established to be (5S,6R,8S,10R)‐6‐hydroxyeudesma‐4(15),7(11)‐diene‐12,8‐olide ( 1 ), 6α‐hydroxyeudesma‐4(15),7(11),8(9)‐triene‐12,8‐olide ( 2 ), 8,12‐epoxy‐1β‐hydroxyeudesma‐4(15),7,11‐trien‐6‐one ( 3 ), 12‐oxochloraniolide A ( 4 ), and (4α)‐8‐hydroxy‐12‐norcardina‐6,8,10‐trien‐11‐one ( 5 ), respectively. Among the isolates, compound 2 , zederone epoxide ( 8 ), spicachlorantin G ( 13 ), chloramultilide A ( 14 ), shizukaol B ( 15 ), and spicachlorantin B ( 17 ) showed significant anti‐neuroinflammatory effects by inhibiting nitric‐oxide (NO) production in lipopolysaccharide (LPS)‐stimulated murine BV‐2 microglial cells with relatively low cytotoxicity.  相似文献   

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