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A new species of Pseudocercospora
假尾孢属一新种

GUO Ying-Lan,
郭英兰

菌物学报 , 2011,
Abstract: Pseudocercospora merremiae sp. nov. on Merremia umbellata subsp. orientalis is reported. Diagnosis, illustration and discussion are provided. The type specimen is deposited in HMAS.
Whole genome sequencing of the fish pathogen Francisella noatunensis subsp. orientalis Toba04 gives novel insights into Francisella evolution and pathogenecity  [cached]
Sridhar Settu,Sharma Animesh,Kongshaug Heidi,Nilsen Frank
BMC Genomics , 2012, DOI: 10.1186/1471-2164-13-598
Abstract: Background Francisella is a genus of gram-negative bacterium highly virulent in fishes and human where F. tularensis is causing the serious disease tularaemia in human. Recently Francisella species have been reported to cause mortality in aquaculture species like Atlantic cod and tilapia. We have completed the sequencing and draft assembly of the Francisella noatunensis subsp. orientalisToba04 strain isolated from farmed Tilapia. Compared to other available Francisella genomes, it is most similar to the genome of Francisella philomiragia subsp. philomiragia, a free-living bacterium not virulent to human. Results The genome is rearranged compared to the available Francisella genomes even though we found no IS-elements in the genome. Nearly 16% percent of the predicted ORFs are pseudogenes. Computational pathway analysis indicates that a number of the metabolic pathways are disrupted due to pseudogenes. Comparing the novel genome with other available Francisella genomes, we found around 2.5% of unique genes present in Francisella noatunensis subsp. orientalis Toba04 and a list of genes uniquely present in the human-pathogenic Francisella subspecies. Most of these genes might have transferred from bacterial species through horizontal gene transfer. Comparative analysis between human and fish pathogen also provide insights into genes responsible for pathogenecity. Our analysis of pseudogenes indicates that the evolution of Francisella subspecies’s pseudogenes from Tilapia is old with large number of pseudogenes having more than one inactivating mutation. Conclusions The fish pathogen has lost non-essential genes some time ago. Evolutionary analysis of the Francisella genomes, strongly suggests that human and fish pathogenic Francisella species have evolved independently from free-living metabolically competent Francisella species. These findings will contribute to understanding the evolution of Francisella species and pathogenesis.
Native Expanding Merremia boisiana Is Not More Allelopathic than Its Non-Expanding Congener M. vitifolia in the Expanded Range in Hainan  [PDF]
Qiaoqiao Huang, Yide Shen, Zhiwei Fan, Mingguang Li, Hanting Cheng, Xiaoxia Li
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.44096
Abstract: Exotic invaders may possess novel biochemical weapons that native plants do not have, and these novel biochemical weapons may be more allelopathic than those from native plants to other native competitors. During range expansion, native species also encounter many new plant competitors. Thus, allelochemicals from native expanding species may also be more novel and allelopathic than those from non-expanding species to other plant competitors in the expanded range. We test this hypothesis using the native expanding Merremia boisiana and its non-expanding congener M. vitifolia in year 2012 inthe expanded range inHainan. In petridish bioassays, we found that aqueous extracts of M. boisiana leaves were often less inhibitory or more stimulatory to seed germination and seedling growth of five vegetable species than those of M. vitifolia leaves. In pot culture, we also found that aqueous leaf extracts of the two congeners could both inhibit the growth of a naturally co-occurring plant Paederia scanden, but their effects did not differ from each other. These results indicate that while allelopathy may contribute to the competitive ability of M. boisiana, it may not act as a novel weapon explaining its success in the expanded range in Hainan.
Allelopathic Effects of Ludwigia decurrens and L. adscendens subsp. diffusa on Germination, Seedling Growth and Yield of Corchorus olitorious L.  [cached]
Ayobola A. Moninuola SAKPERE,Matthew OZIEGBE,Idowu Arinola BILESANMI
Notulae Scientia Biologicae , 2010,
Abstract: This study examined the allelopathic effect of Ludwigia decurrens and L. adscendens exudates on germination, seedling growth (hypocotyl and radicle elongation), seedling mortality, vegetative growth and reproductive yield of Corchorus olitorious. Ludwigia decurrens, L. adscedens exudates and tap water (control) were applied to seeds of Corchorus olitorious over a period of 15 days and to 3 weeks old seedling for a period of 4 weeks. Ludwigia exudates had no inhibitory effect on the germination percentage of C. olitorious, but the exudates from the two Ludwigia spp. induced mortality rate of the 15 day old seedlings (control: 5.00%, L. decurrens: 17.50%, L. adscendens: 26.88%) and a significant decrease in seedling elongation (hypocotyl and radicle length) of C. olitorious. For the vegetative growth experiment, results showed that the stem length, stem fresh weight and leaf area of C. olitorious were significantly inhibited during week 6 (P<0.05) by L. decurrens and L. adscendens exudates. For reproductive yield experiment, number of pods per plant was significantly reduced on week 11. The high percentage mortality rate observed in seedlings might be an important factor in reducing seedling survival of Corchorus olitorious in habitats where the two Ludwigia spp are dominant.
The Extract Obtained from Two Radish Cultivars (Raphanus sativus L. and Raphanus sativus L. var. radikula) Using Liquid Nitrogen Is Germination of Sterile Oats (Avena sterilis Subsp. sterilis) and Allelopathic Effect on Seedling Growth
Duygu Sisek, Suleyman Turkseven, Suleyman Topal
Open Access Library Journal (OALib Journal) , 2019, DOI: 10.4236/oalib.1105561
Abstract:
The purpose of this study is to determine the allelopathic effects of extracts obtained by using liquid nitrogen from the plant of Antep radish (Raphanus sa-tivus L.) and little radish (Raphanus sativus L. var. radikula) on germination and seedling growth of sterile oats. The experiments were carried out in six groups with root, stem and root stem mixed extracts of radish plants (Antep and little radish). A novel method that we developed based on the principle of liquid nitrogen crushing was used for extraction. According to this method, Antep radish and little radish plant parts were frozen with liquid nitrogen aid and then crushed to powder. These powders obtained were stored at ?20?C for nine months until the experiments were established. The aqueous solutions prepared at specific concentrations (0%, 1%, 2%, 4%, 8%, 16%) from the ob-tained radish powders were applied as 5 ml to per each petri dishes contain 10 seeds on Whatman No: 1 double layer filter paper. Experiments were carried out in six replicates for each concentration. The prepared petri dishes were kept in the incubator at 15?C for 15 days. At the end of the experimental period, the number of germination of the seeds of sterile wild oat plant was evaluated by measuring the length of seedling root and stem. As a result, as the concentra-tion of allelopathic solutions increased in all experimental groups, the number of germination and root and stem lengths of sterile wild oats decreased. Alt-hough allelopathic effects in all three experimental groups were observed in terms of germination number and seedling lengths, the most significant effects were observed in the results of Antep radish root experiments. In this experi-ment group, the inhibition rate of root and stem length of weed seeds at a con-centration of 16% were 86% and 82%, respectively, when compared to the control. In addition, the germination number was reduced by 74.36% in the seeds at the highest concentration compared to the control. As a result of the study, it was determined that samples of radish plant crushed with liquid nitro-gen were stored for a long time and showed high allelopathic effect on sterile wild oats plant.
Morfologia polínica de espécies do gênero Merremia Dennst. (Convolvulaceae) ocorrentes no Estado da Bahia, Brasil
Leite, Kelly Regina Batista;Sim?o-Bianchini, Rosangela;Santos, Francisco de Assis Ribeiro dos;
Acta Botanica Brasilica , 2005, DOI: 10.1590/S0102-33062005000200014
Abstract: species of the genus merremia (convolvulaceae) from state of bahia were surveyed, and their pollen grains were studied by usual methods. nine taxa were recorded: m. aegyptia (l.) urb., m. cissoides (lam.) hallier f., m. digitata (spreng.) hall. f. var. digitata, m. digitata var. ericoides (meissn.) austin & staples, m. dissecta (jacq.) hall. f. var. edentata (meisn.) o'donell, m. flagellaris (choisy) o'donell, m. macrocalyx (ruiz et pav.) o'donell, m. tomentosa (choisy) hall. f. and m. umbellata (l.) hall. f. in m. digitata var. digitata and m. flagellaris, the pollen grains presented irregular colpi and with three and six long colpi. thick apertural membrane was observed in m. aegyptia, m. cissoides, m. digitata var. ericoides; presence with opercules in m. aegyptia, m. cissoides and m. digitata var. ericoides pollen grains. six-aperturated pollen grains are zonocolpate (in m. umbellata) or pantocolpate (in m. digitata var. digitata, m. digitata var. ericoides and m. flagellaris); more than one apertural type can be found grains in the same specimen. the palinological data corroborate the placement of m. aegyptia, m. dissecta var. edentata and m. macrocalyx in m. sect. schizips, m. umbellata in m. sect. xanthips and other ones in m. sect. cissoides. in the latter section, excluding m. tomentosa, all species belong to the complex m. digitata, in which they are not well delimitated.
The in vitro antibacterial activity of Hedyotis Umbellata  [cached]
Rekha S,Srinivasan V,Vasanth Saradha,Gopal R
Indian Journal of Pharmaceutical Sciences , 2006,
Abstract: The in vitro antibacterial activity of Hedyotis umbellata (aerial parts) was investigated against Staphyllococcus aureus, S. citreus, Streptococcus faecalis, Bacillus subtilis, Escherichia coli, Klebsiella aerogenes, Shigella flexneri, and Pseudomonas aeruginosa at 20 mg/ml, whereas the alcohol extract did not show any promising activity. The ethyl acetate eluate of the chloroform extract showed a zone of inhibition of 10mm against B. subtilis and E. coli , at 20 mg/ml.
Considera??es sobre a pariparoba oficial Pothomorphe umbellata (L.) Miq.
Moraes, Marlene Silva;
Revista Brasileira de Farmacognosia , 1986, DOI: 10.1590/S0102-695X1986000100012
Abstract: the author presents a review of the pharmacognostic studies of pothomorphe umbellata (l.) miq., medicinal specimen officialy known as pariparoba.
NUEVO HALLAZGO DE TARASA UMBELLATA KRAPOV. (MALVACEAE)
Marticorena,Alicia; Valdivieso,José Antonio; Baeza,Carlos M;
Gayana. Botánica , 2007, DOI: 10.4067/S0717-66432007000200006
Abstract: a new discovery of tarasa umbellata krapov. (malvaceae) in talca, central chile, is presented. the fruits were unknown until now. the description of the fruits, commentaries about the habitat, chromosome number and the relation with tarasa reichei (phil.) krapov. is made
Teucrium x mailhoi Giraudias nothosubsp. orientalis nova, un nou híbrid del vessant meridional dels Pirineus  [cached]
Soriano, I.,Aymerich, P.
Collectanea Botanica , 2011,
Abstract: Teucrium x mailhoiGiraudias nothosubsp. orientalis nova, a new hybrid from the Southern face of the Pyrenees.- We give advice about a small population of Teucrium aureum Schreb. subsp. aureum x T. pyrenaicum L. subsp. guarensis P. Monts., observed in the Southern slope of the Serra de Moixeró (Eastern Pyrenees), which is proposed as a new nothosubspecies. We present also a morphological comparison between the hybrid and the two presumed parental species, and some images of herbarium specimens and plants in the field. [ca] Teucrium x mailhoi Giraudias nothosubsp. orientalis nova, un nou híbrid del vessant meridional dels Pirineus.- Donem notícia de l’observació d’una petita població de l’híbrid entre Teucrium aureum Schreb. subsp. aureum i T. pyrenaicum L. subsp. guarensis P. Monts. al vessant sud de la serra de Moixeró (Pirineus orientals), que proposem com a nova notosubespècie. Fem també una comparació morfològica entre l’híbrid i els dos presumptes parentals, i en presentem imatges de materials d’herbari i de la població natural. [es] Teucrium x mailhoi Giraudias nothosubsp. orientalis nova, un nuevo híbrido de la vertiente sur pirenaica.- Damos a conocer una peque a población de un híbrido entre Teucrium aureum Schreb. subsp. aureum y T. pyrenaicum L. subsp. guarensis P. Monts. de la vertiente sur de la Serra de Moixeró (Pirineos orientales), que proponemos como nueva notosubespecie. Presentamos asimismo una comparación de la morfología del híbrido con la de los dos presuntos parentales así como algunas imágenes tanto de especímenes de herbario como de la población natural.
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