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1162. Life cycle and growth pattern of the endangered myrmecophilous Microdon myrmicae (Diptera: Syrphidae)
- Creator:
- Witek, Magdalena, Canterino, Sara, Balletto, Emilio, and Bonelli, Simona
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Syrphidae, hoverflies, Microdon myrmicae, ants, Myrmica, Maculinea, social parasites, larval ecology, polymorphic growth, 2, and 59
- Language:
- English
- Description:
- In Europe there are only a few species of the syrphid fly Microdon, which live in the nests of various genera of ants. For most of these rare flies, details of their biology, larval behaviour and relationships with their hosts are still not yet well known. In this paper we present data on the life cycle, feeding behaviour and growth pattern of Microdon myrmicae, a social parasite of Myrmica ants and compare it with two species of Maculinea butterflies similarly parasitizing Myrmica ant colonies. M. myrmicae has three larval instars and overwinters as a third instar. Eggs and 1st instar larvae are ignored by ants, which indicate that they are “chemically insignificant”. 2nd and 3rd instar larvae feed on small ant brood. M.myrmicae larvae grow rapidly from May to July and later in the year the host colony only serves as shelter for overwintering. Like Maculinea alcon, larvae of M. myrmicae are numerous in Myrmica nests and more numerous than those of Maculinea teleius. Since the larvae of Microdon feed on an abundance of young ant brood, they experience low level of scramble competition and although many may develop in an ant’s nest they have probably little effect on host colony fitness., Magdalena Witek ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1163. Life cycle and settlement of an Australian isolate of Ichthyophthirius multifiliis Fouquet, 1876 from rainbow trout
- Creator:
- Forwood, James M, Harris, James O, Landos, Matt, and Deveney, Marty R
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- teplota, nemoci, temperature, diseases, Ichthyophthirius multifiliis, disease management, salinity, 2, and 59
- Language:
- English
- Description:
- Ichthyophthirius multifiliis Fouquet, 1876, a ciliate parasite, is a cosmopolitan and problematic parasite of cultured freshwater fish. Each geographical isolate of I. multifiliis has variations in life cycle timing under different abiotic water conditions, such as temperature and salinity. We assessed the effects of salinity and temperature on the development and the preferred settlement site of a temperate Australian isolate of I. multifiliis. The time until theront release was significantly different between each temperature; development time was longest at 5 °C with a mean time of 189 h and decreased to a mean time of 11.7 h at 30 °C. At 5 °C our isolate produced a mean of 267 theronts per tomont, which increased to a mean of 493 theronts at 25 °C and reduced to a mean of 288 theronts at 30 °C. Theront length showed an inverse relationship to temperature; mean length was 62 μm at 5 °C and 41 μm at 30 °C. Our isolate reproduced faster at all temperatures and a greater sensitivity to salinity than all reported profiles for temperate isolates. Parasite abundance was highest on the dorsal region of the fish. An accurate understanding of temperature-life cycle information and optimal region to sample for surveillance will aid in the development of specific management plans for the Australian isolate of I. multifiliis, facilitating the strategic timing of treatments., James M. Forwood, James O. Harris, Matt Landos, Marty R. Deveney., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1164. Life cycle of Hepatozoon affluomaloti sp. n. (Apicomplexa: Haemogregarinidae) in crag lizards (Sauria: Cordylidae) and in culicine mosquitoes from South Africa
- Creator:
- As, Johann Van, Davies, Angela J, and Smit, Nico J
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitologie, parasitology, gamonts, merogonic stage, oocysts, sporocysts, sporozoites, transmission, 2, and 59
- Language:
- English
- Description:
- A new haemogregarine species Hepatozoon affluomaloti sp. n. is described from erythrocytes in the peripheral blood of crag lizards Pseudocordylus melanotus (Smith) and Pseudocordylus subviridis (Smith) (Sauria: Cordylidae) from mountainous regions in the Eastern Free State, South Africa. This species can be distinguished from all other congeners based on its large size, staining properties and life cycle development in its vector, Culex (Afroculex) lineata (Theobald) (Diptera: Culicidae). Mature gamonts stain mostly uniformly pinkish-purple with Giemsa, sometimes containing darker azurophilic granules anterior and posterior to the nucleus. The reflexed posterior extremity of the gamont stage sometimes stains slightly deeper purple and the nucleus is dense and placed in the posterior third of the parasite body. Merogonic stages of this haemogregarine occur in the liver tissues of P. melanotus with dizoic meronts. Macromeronts contains 2-7 macromerozoites and micromeronts contains 9-24 micromerozoites. Sporogonic developmental stages found in the proposed final host and vector, C. lineata, include large oocysts, measuring 54 × 48 µm on average. Sporulating oocysts with 8 nuclei are present in mosquitoes 6-7 days post-feeding on infected lizards. Sporocysts with mature sporozoites measure 31.0 × 21.8 µm on average and each contains 2-8 large sporozoites. It is suggested that transmission of infective sporozoites is achieved through predation of lizards on mosquitoes., Johann Van As, Angela J. Davies, Nico J. Smit., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1165. Life in two dimensions or keeping your head down: lateral exuvial splits in leaf-mining larvae of Pachyschelus (Coleoptera: Buprestidae) and Cameraria (Lepidoptera: Gracillariidae)
- Creator:
- Grebennikov, Vasily V.
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Leaf-mining, moult, exuviae, larvae, Buprestidae, Pachyschelus, Gracillariidae, Cameraria, 2, and 59
- Language:
- English
- Description:
- This paper describes previously unreported lateral cuticle splits occurring during the moulting of larvae of the leaf-miners Pachyschelus laevigatus (Say, 1839) (Coleoptera: Buprestidae) and Cameraria sp. (Lepidoptera: Gracillariidae). In these species the cuticle does not split dorsally during the larval/larval moults as in most insects, but laterally, thus permitting the larva to leave its exuviae sideways rather than vertically. This previously overlooked phenomenon is hypothesized to have evolved independently in both taxa and is an adaptation to life in the vertically limited space of their mines and, therefore, might be found in other organisms confined to similar conditions. The exuvial split in the larva to pupa moult of Cameraria sp. taking place inside a relatively tick and firm cocoon is, however, of the regular dorso-medial type, and, therefore, two different successive types of moult occur within a single ontogenesis. For comparative purposes the common dorsal exuvial split is described and illustrated for the leaf-mining larvae of Profenusa alumna (Hymenoptera: Tenthredinidae), Sumitrosis rosea (Coleoptera: Chrysomelidae) and the free-living Satonius fui (Coleoptera: Torridincolidae)., Vasily V. Grebennikov., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1166. Life style change and reverse cholesterol transport in obese women
- Creator:
- Ivana K. Lesná, Pavel Suchánek, Jan Kovář, and Rudolf Poledne
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biochemie. Molekulární biologie. Biofyzika, biochemie, cholesterol, lipoproteiny, životní styl, biochemistry, lipoproteins, life style, reverzní transport cholesterolu, reverse cholesterol transport, cholesterol efflux, lipoprotein metabolism, 2, and 577
- Language:
- English
- Description:
- HDL cholesterol resp. apolipoprotein A1 concentrations are tools to estimate individual CVD risk, although only a part of HDL particles participate in reverse cholesterol transport (RCT). This discrepancy was analyzed in life style change based on increase of physical activity and dietary counseling. Efflux of cholesterol from pre-labeled macrophages to plasma acceptors of tested individuals was used as an RCT measure. Changes of lipoprotein parameters, glucose, fasting insulin concentrations and RCT were analyzed in 15 obese women after 9-week intervention consisted of 5 sessions of increased physical activity per week. Controlled increase in physical activity for 9 weeks induced a decrease of body weight averaging 9 kg (ranged from 2.3 to 15.5 kg). The intervention leads to significant decreases of triglycerides, apoprotein A1 and apoprotein B concentration, whereas total cholesterol, LDL cholesterol and HDL cholesterol did not change significantly. The increase of RCT was not significant, but there was highly significant negative correlation between individual decrease of body weight and an increase of RCT. Significant increase of RCT was found in 13 persons with a weight reduction more than 3.5 kg. Substantial weight loss is necessary to increase RCT., I. Králová Lesná ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1167. Life-history constraints in inaccurate Batesian myrmecomorphic spiders (Araneae: Corinnidae, Gnaphosidae)
- Creator:
- Stanislav Pekár and Jarab, Martin
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, entomologie, Formicidae, prey, trophic niche, clutch size, copulation, courtship, 2, and 59
- Language:
- English
- Description:
- Accurate Batesian mimicry is known to impose constraints on some traits of the mimic, such as foraging or reproductive behaviour. It is not known whether life-history traits of inaccurate Batesian mimics are constrained as well. We studied selected life-history traits of three spider species, Liophrurillus flavitarsis, Phrurolithus festivus (both Corinnidae), and Micaria sociabilis (Gnaphosidae), that are inaccurate mimics of ants. Namely, we were interested in how myrmecomorphy (ant-like resemblance) constrains their circadian activity, trophic niche and reproductive behaviour. The spiders were found to have diurnal activity like their models, whereas their close relatives have nocturnal activity. The three mimics do not catch ants, nor do they use food resources of ants, but catch various tiny invertebrates that occur in the vicinity of their models. Their trophic niche seems to be constrained by occurrence among ants. Absence of courtship and long lasting copulation, in a position that does not provide protective resemblance, do not seem to be constrained by mimicry in the three species. Comparative analysis of fecundity in mimetic and non-mimetic spiders showed that clutch size is also not constrained. Unlike in accurate mimics, life-history traits of inaccurate myrmecomorphs appear not to be constrained. and Stano Pekár, Martin Jarab.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1168. Light availability and soil flooding regulate photosynthesis of an imperiled shrub in lowland forests of the Mississippi Alluvial Valley, USA
- Creator:
- Lockhart, B. R., Gardiner, E. S., Leininger, T. D., Devall, M. S., Wilson, A. D., Connor, K. F., Hamel, P. B., and Schiff, N. M.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- plasticita, plasticity, Mississippi, oblast čepele listu, interakce, blade area, blade mass, interaction, pondberries, 2, and 581
- Language:
- Multiple languages
- Description:
- Physiological responses to light availability and soil flooding on Lindera melissifolia (Walt.) Blume were studied. Shrubs were grown under 70, 37 or 5% of full sunlight with either 0, 45, or 90 d of soil flooding. We measured leaf photosynthetic rate (PN) to test the hypothesis that soil flooding reduces PN in L. melissifolia following shrub acclimation to low light availability. Results showed that light availability and soil flooding interacted to affect PN. In the 0 d and 45 d flooding regimes (flood water removed 36-39 d prior to measurement), PN was similar between shrubs receiving 70% or 37% light, and these shrubs had 147% greater PN than shrubs receiving 5% light. Shrubs receiving 90 d of soil flooding had similar low rates of area-based PN regardless of light level. Similar PN between 0 d and 45 d flooded shrubs indicated physiological recovery following removal of flood water., B. R. Lockhart, E. S. Gardiner, T. D. Leininger, M. S. Devall, A. D. Wilson, K. F. Connor, P. B. Hamel, N. M. Schiff., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1169. Light dependence of carboxylation capacity for C3 photosynthesis models
- Creator:
- Bunce, J. A.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- oxid uhličitý, teplota, fazole, carbon dioxide, temperature, beans, změna klimatu, climate change, modeling, C3, CO2, quinoa, elektronová doprava, mezibuněčná koncentrace CO2, list, common bean, electron transport, intercellular CO2 concentration, leaf, 2, and 581
- Language:
- Multiple languages
- Description:
- C3 photosynthesis at high light is often modeled by assuming limitation by the maximum capacity of Rubisco carboxylation (VCmax) at low CO2 concentrations, by electron transport capacity (Jmax) at higher CO2 concentrations, and sometimes by triose-phosphate utilization rate at the highest CO2 concentrations. Net photosynthetic rate (PN) at lower light is often modeled simply by assuming that it becomes limited by electron transport (J). However, it is known that Rubisco can become deactivated at less than saturating light, and it is possible that PN at low light could be limited by the rate of Rubisco carboxylation (VC) rather than J. This could have important consequences for responses of PN to CO2 and temperature at low light. In this work, PN responses to CO2 concentration of common bean, quinoa, and soybean leaves measured over a wide range of temperatures and PPFDs were compared with rates modeled assuming either VC or J limitation at limiting light. In all cases, observed rates of PN were better predicted by assuming limitation by VC rather than J at limiting light both below and above the current ambient CO2. One manifestation of this plant response was that the relative stimulation of PN with increasing the ambient CO2 concentration from 380 to 570 µmol mol-1 did not decrease at less than saturating PPFDs. The ratio of VC to VCmax at each lower PPFD varied linearly with the ratio of PN at low PPFD to PN at high PPFD measured at 380 µmol(CO2) mol-1 in all cases. This modification of the standard C3 biochemical model was much better at reproducing observed responses of light-limited PN to CO2 concentrations from pre-industrial to projected future atmospheric concentrations., J. A. Bunce., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1170. Light induction of nonphotochemical quenching, CO2 fixation, and photoinhibition in woody and fern species adapted to different light regimes
- Creator:
- Wong, S.-L., Huang, M.-Y., Chen, C.-W., and Weng, J.-H.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, light adaptation, NPQ, photoinhibition, photosynthetic induction, photosynthetic rate, 2, and 581
- Language:
- Multiple languages
- Description:
- We aimed to find out relations among nonphotochemical quenching (NPQ), gross photosynthetic rate (PG), and photoinhibition during photosynthetic light induction in three woody species (one pioneer tree and two understory shrubs) and four ferns adapted to different light regimes. Pot-grown plants received 100% and/or 10% sunlight according to their light-adaptation capabilities. After at least four months of light acclimation, CO2 exchange and chlorophyll fluorescence were measured simultaneously in the laboratory. We found that during light induction the formation and relaxation of the transient NPQ was closely related to light intensity, light-adaption capability of species, and PG. NPQ with all treatments increased rapidly within the first 1-2 min of the light induction. Thereafter, only species with high PG and electron transport rate (ETR), i.e., one pioneer tree and one mild shade-adapted fern, showed NPQ relaxing rapidly to a low steady-state level within 6-8 min under PPFD of 100 μmol(photon) m-2 s-1 and ambient CO2 concentration. Leaves with low PG and ETR, regardless of species characteristics or inhibition by low CO2 concentration, showed slow or none NPQ relaxation up to 20 min after the start of low light induction. In contrast, NPQ increased slowly to a steady state (one pioneer tree) or it did not reach the steady state (the others) from 2 to 30 min under PPFD of 2,000 μmol m-2 s-1. Under high excess of light energy, species adapted to or plants acclimated to high light exhibited high NPQ at the initial 1 or 2 min, and showed low photoinhibition after 30 min of light induction. The value of fastest-developing NPQ can be quickly and easily obtained and might be useful for physiological studies., S.-L. Wong, M.-Y. Huang, C.-W. Chen, J.-H. Weng., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public