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71.
《Bioscience, biotechnology, and biochemistry》2013,77(7):1448-1450
Jasmonates and related compounds were found to elicit the seed germination of the important root parasites, clover broomrape (Orobanche minor Smith) and witchweed [Striga hermonthica (Del.) Benth]. The stimulation of seed germination by the esters was more effective than by the corresponding free acids, and methyl jasmonate (MJA) was the most active stimulant among the compounds tested. 相似文献
72.
A. G. Hocken 《New Zealand journal of zoology.》2013,40(4):299-304
Abstract This work presents a database of weights of normal internal organs for the blue penguin, Eudyptula minor. During a necropsy study of 213 adult and fledged immature blue penguins, external body measurements and internal organ weights were recorded. The relationship between organ weights and body weights shows that the liver and abdominal fat pad are most closely correlated with the body mass index, a quantitative indication of adequacy of condition. 相似文献
73.
The genus Mystrium is revised for the Malagasy region. Six species, Mystrium barrybressleri
sp. n., Mystrium labyrinth
sp. n., Mystrium eques
sp. n., Mystrium mirror
sp. n., Mystrium shadow
sp. n., and Mystrium janovitzi
sp. n. are described as new. Two existing names, Mystrium fallax Forel and Mystrium stadelmanni Forel, are synonymized with Mystrium voeltzkowi Forel and Mystrium mysticum Roger, respectively. All recognized species, including species outside of the Malagasy region, are assigned to one of the three newly proposed species groups. The associations between existing names and males are reexamined, and males of eight of the ten Malagasy species are described or redescribed. The taxonomic history of Mystrium highlights the importance of using unique identifiers when designating type specimens and the use of deposited vouchers in phylogenetic and ecological studies. Keys to species for workers, queens, and males are provided. Furthermore, a neotype for Mystrium mysticum is designated, as well as lectotypes for Mystrium camillae Emery, Mystrium rogeri Forel, Mystrium fallax Forel, Mystrium oberthueri Forel, Mystrium stadelmanni Forel, and Mystrium voeltzkowi Forel. Stigmatomma gingivale (Brown) is reassigned to Amblyopone as comb. rev. and Amblyopone awa Xu & Chu, Amblyopone kangba Xu & Chu, Amblyopone meiliana Xu & Chu, and Amblyopone zomae Xu & Chu are transferred to the genus Stigmatomma as comb. n. 相似文献
74.
《Journal of Plant Interactions》2013,8(3):271-282
Coastal-ridge plains are progradational landforms composed of elevated ridges and low-lying swales. The transitions between ridges and swales are steep, promoting dynamic shifts between xeric and mesic systems. Two understory plants that co-occur in ridge plains of North American mid-Atlantic maritime forests are Sabal minor and Ilex vomitoria. As coastal-ridge plains foster varying amounts of surface and sub-surface water driven largely by topography, the purpose of this study was to evaluate plant–water relations and chlorophyll a fluorescence in these two species. Ridge plants had lower leaf- and xylem-water potentials, lower osmotic potential (I. vomitoria), and lower symplastic water content (S. minor). Although there were no differences in potential- and effective-quantum yields, there were decreases in fluorescence performance index for ridge I. vomitoria and swale S. minor. While the data support potential water-stress conditions in ridge plants of both species, the data also suggest that I. vomitoria and S. minor use different physiological processes to tolerate hydrologically dynamic ridge–swale maritime forests. 相似文献
75.
The aim of this study was to investigate the ability of Lemna minor for Toluidine Blue (TB) removal. Influence of the initial concentration over the removal process was considered. Experimental data have been analyzed using Langmuir, Freundlich, Dubinin–Radushkevich (D–R), and Elovich isotherm models. In addition, several kinetic models, pseudo-first-, pseudo-second-order, intraparticle and film diffusion models were considered. Langmuir and Freundlich isotherm suggested a favorable adsorption of TB by Lemna minor plants. From the D–R the mean free energy was calculated to be 11.18 kJ/mol, which indicates that TB adsorption was characterized by a chemisorption process. Kinetic studies showed that liquid film diffusion plays an important role during the process. Adsorption capacities of up to 26.69 mg/g and a high capacity of adaptation indicated that phytoremediation using Lemna minor could be a valuable alternative for dyes removal from wastewaters. 相似文献
76.
B. L. WOODWORTH B. P. FARM C. MUFUNGO M. BORNER & J. OLE KUWAI 《African Journal of Ecology》1997,35(4):326-334
An aerial photographic census of flamingos ( Phoenicopterus minor and P. ruber) was conducted on 20 July 1994 on nine lakes in Tanzania: Lakes Natron, Manyara, Magadi (Ngorongoro), Burungi, Embagai, Eyasi, Lagarja, Masek, and Ambussel. This census, conducted concurrently with a survey in Kenya, documented the numbers and distribution of flamingos in the Rift Valley Lakes of East Africa. The total population size of flamingos in the Tanzanian lakes surveyed was |mF907,000. The largest concentrations in Tanzania were found in Lake Natron and Embagai Crater Lake. Although flamingos are known to breed in Lake Natron, no evidence of breeding was observed during the survey. The total estimate for the southern Kenya and northern Tanzania Rift Valley was |mF2·8 million. Trends in flamingo populations, survey methodology, and future monitoring needs are discussed. 相似文献
77.
Frank J. Bonaccorso John R. Winkelmann Elizabeth R. Dumont Katherlne Thibault 《Biotropica》2002,34(1):127-135
Lesser bare–backed bats (Dobsonia minor [Pteropodidae]) are solitary and roost in foliage of understory and subcanopy trees in lowland rain forest. These 70–90 gram frugivorous bats forage in primary and secondary forest and in abandoned gardens. At the Kau Wildlife Area in Papua New Guinea, movements (N = 1041) of four males and four females fitted with radio transmitters were monitored for 1 to 18 months. Mean home range within 30–day sampling periods was 5.1 ha (N = 12). There were no significant differences in home ranges by sex or by dry–wet season. Females, however, had significandy larger mean core–use areas than males (1.43 ± 0.61 and 0.65 ±0.16 ha, respectively). There was moderate overlap in home range and core–use areas among some simultaneously tracked animals. The long axes of home ranges varied from 150 to 1150 m and the mean was significantly larger in females. Individuals commuted from day roosts to multiple feeding areas, sometimes resulting in disjunct core–use areas and home ranges. Fruits of native Fiats species and the exotic shrub Piper attuncum were staple food items. Piper aduncum grew as dense clusters within early successional habitats, and individual plants ripened 5–20 fruits per night throughout the year. Ficus spp. grew in primary and secondary forest and fruited asynchronously, but individual trees produced tens to thousands of ripe fruits over 7 to 10 days. Three adult female D. minor were tracked over multiple periods spanning 2.5–18 months. Although each female continued to visit a core–use area containing P. aduncum throughout the study, turnover of other core–use areas reflected the ephemeral locations of fruiting fig trees. 相似文献
78.
The effect of feeding two different diets, containing 38 and 45% protein and 35 and 28% lipid, respectively, on growth as well as performance of the digestive proteases (total protease at pH 1·5, 7·0, 9·0 and 10·0) and carbohydrases (total carbohydrase, α-amylase and α-glucosidase) of a new candidate species for aquaculture, the carnivorous spotted wolffish Anarhichas minor (Teleostei, Anarhichadidae), was investigated. No significant growth differences were observed when feeding high protein (HP) or low protein (LP) levels ( P > 0·05), although the LP group exhibited slightly higher protease activity and capacity ( P > 0·05), mostly at the anterior end of the intestine and at alkaline pH. Carbohydrase levels were generally low, apart from α-glucosidase, which was significantly increased for the HP group ( P < 0·05). Implications concerning the performance of digestive enzymes under varying dietary macronutrient levels and effects of digestive enzyme activity on the formulation of efficient artificial diets for carnivorous fishes are discussed in this study. 相似文献
79.
Junji Sagara Tadafumi S. Tochikura Hajime Tanaka Yoshihiro Baba Shoichiro Tsukita Sachiko Tsukita Akihiko Kawai 《Microbiology and immunology》1998,42(4):289-297
In our monoclonal antibody (MAb) stocks prepared against the BHK-21 cell antigens, two (#11875 and 28276) recognized a 21-kDa polypeptide (referred to as VAP21) which is efficiently incorporated into the rabies virion. By using these MAbs, we isolated the cDNA clones that encoded a polypeptide of 144 amino acids from our BHK-21 cell cDNA library. Based on the following evidence, the cDNA was assumed to encode a full-length sequence of VAP21 antigen: i) expression of the cDNA in animal cells resulted in the production of a polypeptide recognized by the two MAbs, and its electrophoretic mobility was the same as that of authentic VAP21 antigen; and ii) immunization with the products from the cDNA-transformed E. coli cells raised specific antibodies in rabbits that recognized a 21-kDa polypeptide in the virion. From the deduced amino acid sequence, it is suggested that the VAP21 antigen has a molecular structure of type-I transmembrane protein containing characteristic proline-rich and glycine-rich regions in its ectodomain. Homology searches resulted in finding homologous sequences (totally about 40% homology) in the human MIC2 gene product (CD99; 32-kDa) of T lymphocytes. These results suggest that the VAP21 antigen in the rabies virion is a cellular CD99-related transmembrane protein. 相似文献
80.
Alexandra J. Townsend Francesco Saccon Vasco Giovagnetti Sam Wilson Petra Ungerer Alexander V. Ruban 《BBA》2018,1859(9):666-675
Non-photochemical quenching (NPQ) of chlorophyll fluorescence is the process by which excess light energy is harmlessly dissipated within the photosynthetic membrane. The fastest component of NPQ, known as energy-dependent quenching (qE), occurs within minutes, but the site and mechanism of qE remain of great debate. Here, the chlorophyll fluorescence of Arabidopsis thaliana wild type (WT) plants was compared to mutants lacking all minor antenna complexes (NoM). Upon illumination, NoM exhibits altered chlorophyll fluorescence quenching induction (i.e. from the dark-adapted state) characterised by three different stages: (i) a fast quenching component, (ii) transient fluorescence recovery and (iii) a second quenching component. The initial fast quenching component originates in light harvesting complex II (LHCII) trimers and is dependent upon PsbS and the formation of a proton gradient across the thylakoid membrane (ΔpH). Transient fluorescence recovery is likely to occur in both WT and NoM plants, but it cannot be overcome in NoM due to impaired ΔpH formation and a reduced zeaxanthin synthesis rate. Moreover, an enhanced fluorescence emission peak at ~679?nm in NoM plants indicates detachment of LHCII trimers from the bulk antenna system, which could also contribute to the transient fluorescence recovery. Finally, the second quenching component is triggered by both ΔpH and PsbS and enhanced by zeaxanthin synthesis. This study indicates that minor antenna complexes are not essential for qE, but reveals their importance in electron stransport, ΔpH formation and zeaxanthin synthesis. 相似文献