he efficacy of natural enemies in controlling pests under field conditions is largely correlated with their capacity to spread within infested crops. In this study the spatial dispersal of the California red scale parasitoid Aphytis melinus DeBach (Hymenoptera: Aphelinidae) was evaluated in the field after augmentative releases. The experiment was conducted in 2007 in six 1-ha plots in a Sicilian citrus orchard under integrated pest management. A total of 180,000 A. melinus adults was released in each of three plots and the other plots were left as untreated control. The flight range of the parasitoid was evaluated, for 35 days after the release, on 16 trees per each plot, located at 20 and 40 m from the central release point using yellow sticky traps activated with Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae) sexual pheromone and by monitoring the percentage parasitism of the scale on fruits and twigs. The effects of the distance from the release point and density of susceptible stages of host on parasitoid dispersal were evaluated. The number of wasps captured during the whole trial was greater in the traps located 20 m from the release point than in those at 40 m and in the control plots. Aphytis melinus dispersed over distances less than 40 m based on both the lower percentage parasitism and numbers captured recorded at distances of 40 m. The results are discussed in the context of the biological control of California red scale in citrus orchards by means of wasp releases. In particular, the release points should be no more than 40 m apart for a quick and homogeneous colonization of the area treated., Lucia Zappala ... [et al.]., and Obsahuje seznam literatury
Dryocosmus kuriphilus (Hymenoptera: Cynipidae), also known as the Asian chestnut gall wasp, is a non-native invasive species that has recently appeared in many regions of Europe, including the Iberian Peninsula. This species is an important pest of chestnut trees in several regions and is of concern for foresters in these areas. The results of this research revealed 14 different hotspots of infestation of D. kuriphilus and resulted in the development of models that predict the distribution of D. kuriphilus in Spain over the next 37 years (2019-2055). These results indicate a rapid spread in all Spanish chestnut forests and identify areas that are theoretically highly suitable and susceptible to colonization by this cynipid based on predictions of three different niche models. Although D. kuriphilus is able to induce galls on all chestnut trees, the models indicate that there are differences in the suitability of the different regions for this species. This differential suitability results in some areas having better environmental conditions than others for D. kuriphilus, which is a factor that should be taken into account in its management and biological control. This study of the current distribution, patterns of dispersal using GIS and potentially suitable areas for D. kuriphilus, using niche models will assist in the management and control of this pest in Spain., Diego Gil-Tapetado, José F. Gómez, Francisco J. Cabrero-Sañudo, José L. Nieves-Aldrey., and Obsahuje bibliografii
In order to use rationally switchgrass (Panicum virgatum L.) introduced in a large scale in semiarid regions on the Loess Plateau of China, we investigated and compared soil water storage dynamics, diurnal and seasonal changes in leaf photosynthetic characteristics, and biomass production of switchgrass grown under three different row spacing (20, 40, and 60 cm). Results indicated that photosynthetic parameters showed a pronounced seasonality. Diurnal course of net photosynthetic rate (P N) was bimodal, showing obvious midday depression, which was mainly due to stomatal limitation in May and June, by nonstomatal limitation in August, and both stomatal and nonstomatal factors in September. Generally, P N, stomatal conductance, instantaneous water-use efficiency, light-saturated net photosynthetic rate, saturation irradiance, and compensation irradiance increased with increasing row spacing. Plant height, leaf width, and a relative growth rate of biomass accumulation were significantly higher at the row spacing of 60 cm, while 20 cm spacing showed significantly higher aboveground biomass production and the biomass water-use efficiency. All these confirmed that soil water is the key limiting factor influencing switchgrass photosynthesis, and suggested that the wide row plantation (i.e., 60 cm) was more beneficial to switchgrass growth, while narrow spacing was in favor of improving switchgrass productivity and water-use efficiency., Z. J. Gao, B. C. Xu, J. Wang, L. J. Huo, S. Li., and Obsahuje seznam literatury
Diurnal dynamics of photosynthetic character of Angelica sinensis, as well as effect of continuous cropping on leaf photosynthetic character, antioxidant enzyme activity and growth of A. sinensis were investigated under field condition. The results showed that the diurnal net photosynthetic rate of A. sinensis in sunny day exhibited a double-peak pattern, and the peaks occurred at 9:45 and 16:45 h, respectively. There was a significant midday depression with A. sinensis, which was caused principally by stomatal factors such as stomatal conductance. The results also showed that net photosynthetic rate (PN), transpiration rate (E), stomatal conductance (gs), intercellular CO2 concentration (Ci), and chlorophyll content (Chl) of A. sinensis plants under continuous cropping were significantly lower than those of the control. The activity of total superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and growth parameters of A. sinensis plants were significantly decreased under continuous cropping condition. This study provides evidence of continuous cropping obstacle effect on photosynthesis, antioxidant enzyme activity, and growth parameters of A. sinensis in a field experiment, which partly explained the yield reduction of A. sinensis in the field, when it was cultivated continuously on the same soil., X. H. Zhang ... [et al.]., and Obsahuje bibliografii
The effects of the diurnal variations in ambient temperature on some C3 and C4 enzymes in the Salsola dendroides and Suaeda altissima species of Chenopodiaceae family were studied during the intensive vegetation period. Activities of phosphoenolpyruvate carboxylase (PEPC) and cytosolic aspartate aminotransferase (AsAT) were shown to decrease in both species in the afternoon and evening. The activity of the mitochondrial AsAT decreased in S. altissima, remained relatively constant in S. dendroides during the day. The activity of alanine aminotransferase was high in the S. dendroides species in the morning and evening and decreased in the S. altissima species by the evening. Glucose-6-phosphate activated PEPC in both species throughout the day. The study of the redox status-regulated C3 enzymes showed temperature-related increases in NADP-glyceraldehyde 3-phosphate dehydrogenase activity in both plants, in fructose-2,6-bisphosphatase activity in the S. altissima species, and in NADP-MDH activity in the S. dendroides species in the afternoon., T. Y. Orujova, S. M. Bayramov, U. A. Gurbanova, H. G. Babayev, M. N. Aliyeva, N. M. Guliyev, Y. M. Feyziyev., and Obsahuje bibliografii
The 24-hour urinary excretion of 6-β-hydroxycortisol (6β-OHC) and the urinary ratio of 6β-hydroxycortisol/cortisol (6β-OHC/UFC) have been proposed as noninvasive probes for human cytochrome P450 3A4 isoform (CYP3A4). In this study, we evaluated within- and between-day variability of 6β-OHC excretion and 6β-OHC/UFC ratio in nine Caucasian men with cardiac disease. Each study participant was asked to collect 24-hour urine specimens during four consecutive days in five standardized time intervals. Concentrations of UFC and 6β-OHC were determined by immunoassay and the high-performance liquid chromatographic (HPLC) method, respectively. The HPLC method was accurate and precise, as indicated by the recovery rate of 96.5-103.3 % and less than 5.2 % and 6.3 % of the coefficient of variation for within-run and between-run assay, respectively. In patients, diurnal variations in UFC and 6β-OHC excretion were parallel. Consequently, 6β-OHC/UFC ratio remained stable during the day. Both, 6β-OHC excretion and 6β-OHC/UFC ratio showed significant relationship between 24-hour value and values measured in corresponding collection periods with best correlations obtained from night interval (22.00-06.00, r = 0.86-0.91). These results indicated that urinary 6β-OHC excretion and 6β-OHC/UFC ratio measured in overnight/morning urine could precisely reflect 24-hour values even in severely ill patients. In addition, a simple and sensitive HPLC method was described for determination of 6β-OHC in urine., S. Mičuda, L. Šišpera, M. Hodač, P. Pařízek, L. Fuksa, E. Brčáková, J. Cerman, J. Cermanová, J. Martínková., and Obsahuje bibliografii a bibliografické odkazy
Plebejus argus is a model species for studying the biology, population ecology and genetics of butterflies. It is patchily distributed throughout most of its European range and considered to be sedentary. Habitats of the butterfly have to encompass two vital larval-resources, i.e. specific food plants and ants, since caterpillars are obligatorily myrmecophilous. The genetic structure of nine P. argus populations (85 individuals) was studied at an intermediate geographical scale (Eastern Poland, diameter of about 400 km) using two kinds of molecular markers i.e. COI (mtDNA) and EF-1α (nuclear gene). Both markers were highly variable with as many as 16 haplotypes and 39 alleles, respectively. Great genetic differentiation in the COI gene was detected (overall FST = 0.411, P < 0.001) but little genetic differentiation in the EF-1α gene (FST = 0.021, P < 0.001). The number of COI haplotypes (ranging from one to seven) and their distribution varied considerably among P. argus populations. The possibility that this heterogeneity was related to Wolbachia was excluded as this endoparasitic bacterium was not detected in samples from any of the populations studied. PCA and SAMOVA analyses divided the sampled populations into two or three groups, which could indicate different colonization routes. Moreover, the differences in genetic differentiation with respect to mtDNA and nuclear markers may suggest male-biased dispersal of P. argus at a larger scale. The hypothesis that females are philopatric is consistent with direct observations of the restricted colonization abilities of the butterfly, while the relatively homogeneous genetic structure revealed by previous allozyme studies in some areas might be explained by the possible higher mobility of males. and Marcin Sielezniew, Donata Ponikwicka-Tyszko, Miroslaw Ratkiewicz, Izabela Dziekanska, Agata Kostro-Ambroziak, Robert Rutkowski.
In this study we report on the structural diversity of adipokinetic hormones (AKHs) in the evolutionarily oldest group of social insects, the termites (Isoptera). Using molecular methods combined with in silico bioinformatic analysis, we studied and compared the sequences coding for these neuropeptides in thirteen species of five families of Isoptera. There are three types of AKH octapeptides in termites: Empusa pennata adipokinetic hormone (Emppe-AKH; pQVNFTPNWamide), Microhodotermes viator corpus cardiacum peptide (Micvi-CC; pQINFTPNWamide) and Periplaneta americana cardioaccelerating hormone (Peram-CAH-I; pQVNFSPNWamide). Of these the Peram-CAH-I was the most frequently bioactive form detected in representatives of four out of the six families studied. The complete AKH preprohormones in the termites studied shared at least an 84% amino acid similarity. In agreement with current phylogenetic scenarios of termites as an internal monophyletic clade nested within cockroaches (Blattaria) in the proximity of the family Blattidae, our phylogenetic analysis of the AKH precursor sequences (in the absence of data for the Cryptocercidae) placed the Blattidae (Periplaneta americana) as a sister group of termites and the AKHs of other cockroach families (Blattellidae and Blaberidae) were more divergent from those of termites. Representatives of the basal termite families Mastotermitidae and Archotermopsidae (but also one rhinotermitid genus Prorhinotermes) occurred separately from the phylogenetically advanced lineage (Rhinotermitidae and Termitidae), and Neotermes (Kalotermitidae) was sister to all other termites included., Veronika Jedličková, Pavel Jedlička, Barbora Špuláková., and Obsahuje bibliografii
The chotts in Algeria are temporary salt lakes recognized as important wintering sites of water birds but neglected in terms of the diversity of the insects living on their banks. Around a chott in the wetland complex in the high plains near Constantine (eastern Algeria), more than half of the species of plants are annuals that dry out in summer, a situation that prompted us to sample the vegetation in spring over a period of two years. Three zones were identified based on an analysis of the vegetation and measurements of the salt content of the soils. Surveys carried out at monthly intervals over the course of a year revealed temporal and spatial variations in biodiversity and abundance of grasshoppers. The inner zone is colonized by halophilic plants and only one grasshopper species (Dericorys millierei) occurs there throughout the year. Two polyphagous species of Calliptamus, which can feed on halophilic plants migrate from adjacent areas into the inner zone in August to feed on the plants growing there. The other species of grasshoppers remain in outer zones as they are unable to feed on halophilic plants. The greatest abundance of grasshoppers from August to winter was recorded in the inner zone and in spring and early summer in the outer zones. The dependence of D. millierei on bushes of Amaranthaceae and its moderate flight ability, features of the family Dericorytidae, limit this species ability to colonize neighbouring chotts., Sarah Mahloul, Abboud Harrat, Daniel Petit., and Obsahuje bibliografii
Tissue samples from wildlife from South Africa were opportunistically collected and screened for haemoprotozoan parasites using nonspecific PCR primers. Samples of 127 individuals were tested, comprising over 50 different species. Haemogregarines were the most commonly identified parasites, but sarcocystids and piroplasmids were also detected. Phylogenetic analyses estimated from the 18S rDNA marker highlighted the occurrence of several novel parasite forms and the detection of parasites in novel hosts. Phylogenetic relationships, which have been recently reviewed, appear to be much more complex than previously considered. Our study highlights the high diversity of parasites circulating in wildlife in this biodiverse region, and the need for further studies to resolve taxonomic issues., D. James Harris, Ali Halajian, Joana L. Santos, Lourens H. Swanepoel, Peter John Taylor, Raquel Xavier., and Obsahuje bibliografii