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101.
Nejmanová J Cvacka J Hrdý I Kuldová J Mertelík J Muck A Nesnerová P Svatos A 《Pest management science》2006,62(3):274-278
Residues of the insect growth regulator diflubenzuron were quantified on horse chestnut (Aesculus hippocastanum L.) leaves treated with a diflubenzuron 480 g litre?1 SC, Dimilin. To analyse the samples, an analytical procedure was developed involving a simple extraction step followed by high‐performance liquid chromatography on an octadecyl‐modified silica column with methanol + 0.01 M ammonium acetate mobile phase. The results showed diflubenzuron to be highly stable on horse chestnut leaves; more than 4 months (127 days) after application, 38% (on average) of the insecticide still remained on/in the leaves. The data confirmed biological observations showing diflubenzuron's long‐term efficacy against the horse chestnut leafminer, Cameraria ohridella Deschka & Dimi?, which is the most important pest of the horse chestnut in Europe. The hypothesis of possible penetration of diflubenzuron into the leaf mass is explored and discussed. Copyright © 2006 Society of Chemical Industry 相似文献
102.
Context
Objective identification of locations on transportation networks, where animal-vehicle collisions (AVC) occur more frequently than expected (hotspots), is an important step for the effective application of mitigation measures.Objectives
We introduce the KDE+ software which is a programmed version of the KDE+ method for effective identification of traffic accident hotspots. The software can be used in order to analyze animal-vehicle collision data.Methods
The KDE+ method is based on principles of Kernel Density Estimation (KDE). The symbol ‘+’ indicates that the method allows for the objective selection of significant clusters and for the ranking of the hotspots. It is also simultaneously applicable to an unlimited number of road segments.Results
We applied the KDE+ method to the entire Czech road network. The hotspots were ranked according to their significance. The resulting hotspots represent a short overall road length which should require a more detailed assessment in the field. The 100 most important clusters of AVC represent, for example, only 19.7 km of the entire road network (37,469 km).Conclusions
We present an objective method for hotspots identification which can be used for AVC data. This method is unique because it determines the significance level of hotspots in an objective way. The prioritization of hotspots allows a transportation manager to effectively allocate resources to a feasible number of identified hotspots. We describe the software, data preparation and present the KDE+ application to AVC data.103.
K. Sharma A. M. Cachi P. Sedlák A. Skřivanová A. Wünsch 《The Journal of Horticultural Science and Biotechnology》2016,91(2):117-121
Sweet cherry (Prunus avium L.) is a self-incompatible species. Determination of the S-genotypes of cherry cultivars is crucial for breeding and to select appropriate cultivars for cross-fertilisation and fruit set. In this study, we characterised the S-genotypes of 25 sweet cherry cultivars, some of which had being bred at the Research and Breeding Institute of Pomology (RBIP), Holovousy, Czech Republic, and others were European cultivars in the RBIP collection. S-genotyping was carried out by polymerase chain reaction using consensus primers for the S-RNase and SFB genes, and capillary electrophoresis. Nine different known S-haplotypes (S1, S2, S3, S4, S5, S6, S9, S13, and S16) were identified and the cultivars were assigned to 12 incompatibility groups. One local cultivar, ‘Pta?ka z Plzně’, originated from a wild forest seedling and used as a pollinator, was assigned to Group 0 of universal donors. The pedigree of some cultivars was confirmed by their S-genotype. This study represents the ?rst comprehensive S-genotype screening of sweet cherry genetic resources in the Czech Republic and will be useful for the design of crossing programmes and orchard management of these sweet cherry cultivars. 相似文献
104.
The interaction of folpet with the glutathione-dependent enzyme demethylation of fenitrothion was studied. In a reaction catalyzed by methyltransferase from rat liver in the presence of 0.3 μmol of glutathione, 0.21 μmol of folpet caused a 100% inhibition of the demethylation of 0.2 μmol of fenitrothion. A parallel study was made on the qualitative and quantitative course of the reaction between folpet and glutathione. Phthalimide was formed as the main degradation product of folpet, but the composition of the degradation products of glutathione was dependent on the molar ratio of the reactants. Compounds absorbing at 267 nm (probably derivatives of 2-thiazolidinethiones) were formed when the ratio of glutathione to folpet was 4.5:1. When this ratio was reversed, oxidized glutathione was the main product. From observations on the course of the enzymatic demethylation of fenitrothion and on the degradation of folpet by glutathione, it appears that in the enzyme demethylation system, the reaction between fungicide and glutathione predominates. 相似文献
105.
Effects of pure plant secondary metabolites on methane production,rumen fermentation and rumen bacteria populations in vitro
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M. Joch J. Mrázek E. Skřivanová L. Čermák M. Marounek 《Journal of animal physiology and animal nutrition》2018,102(4):869-881
In this study, the effects of seven pure plant secondary metabolites (PSM s) on rumen fermentation, methane (CH4) production and rumen bacterial community composition were determined. Two in vitro trials were conducted. In trial 1, nine concentrations of 8‐hydroxyquinoline, α‐ terpineol, camphor, bornyl acetate, α‐ pinene, thymoquinone and thymol were incubated on separate days using in vitro 24‐hr batch incubations. All compounds tested demonstrated the ability to alter rumen fermentation parameters and decrease CH4 production. However, effective concentrations differed among individual PSM s. The lowest concentrations that reduced (p < .05) CH4 production were as follows: 8 mg/L of 8‐hydroxyquinoline, 120 mg/L of thymoquinone, 240 mg/L of thymol and 480 mg/L of α‐ terpineol, camphor, bornyl acetate and α‐ pinene. These concentrations were selected for use in trial 2. In trial 2, PSM s were incubated in one run. Methane was decreased (p < .05) by all PSM s at selected concentrations. However, only 8‐hydroxyquinoline, bornyl acetate and thymoquinone decreased (p < .05) CH4 relative to volatile fatty acids (VFA s). Based on denaturing gradient gel electrophoresis analysis, different PSM s changed the composition of bacterial communities to different extents. As revealed by Ion Torrent sequencing, the effects of PSM s on relative abundance were most pronounced in the predominant families, especially in Lachnospiraceae , Succinivibrionaceae , Prevotellaceae , unclassified Clostridiales and Ruminococcaceae . The CH 4 production was correlated negatively (?.72; p < .05) with relative abundance of Succinivibrionaceae and positively with relative abundance of Ruminococcaceae (.86; p < .05). In summary, this study identified three pure PSM s (8hydroxyquinoline, bornyl acetate and thymoquinone) with potentially promising effects on rumen CH4 production. The PSM s tested in this study demonstrated considerable impact on rumen bacterial communities even at the lowest concentrations that decreased CH4 production. The findings from this study may help to elucidate how PSM s affect rumen bacterial fermentation. 相似文献
106.
Within-field refugiums of Russian wheat aphid, Diuraphis noxia (Kurdj.) in cereals (Hom., Aphididae)
Petr Starý 《Journal of pest science》2001,74(5):124-126
An analysis of the Russian wheat aphid (RWA) (Diuraphis noxia Kurdj.), overpopulated due to extraordinary weather conditions (2000) in the Czech Republic, enabled the identification of several within-field situations ouside of the routine approach. This group, classified as within-field refugium, includes variation due to field relief, some injuries caused by the use of machinery, the unharvested field margins and, last but not least, the volunteer plants. Differences between the RWA populations in these situations and the normal grove are presented and recommended to be taken into consideration in the research on RWA population dynamics and movement. 相似文献
107.
Dinka Grubišić Ljerka Oštrec Tanja Gotlin Čuljak Sylvia Blümel 《Journal of pest science》2007,80(1):21-27
Potato cyst nematodes (PCN) Globodera rostochiensis (Wollenweber, 1923) Behrens, 1975 and Globodera pallida (Stone, 1973) Behrens, 1975 are the most troublesome pests of potatoes worldwide. Since 1968 there have been no investigations
of the presence of PCN in ware potato lands in Croatia although these pests were recognised as an A1 plant-health quarantine
species. After the first discovery of G. rostochiensis in the locality of Belica (Medjimurska County) in 2001, intensive monitoring of the distribution of PCN in Croatia started.
In 2001 G. rostochiensis was detected in 55% of soil samples taken in ware potato lands. In 2002 G. rostochiensis was detected in 4.1% of soil samples and in 0.08% of soil samples in mixed populations with G. pallida. The pathotype Ro1 was found in all tested populations and Ro1 and Pa 2/3 were detected in populations from localities Vidovec,
Ivanovec and Sivice. In 2003 G. rostochiensis was detected in 1.03% of soil samples, and also in 12.8% of soil samples collected in 2004. In 2003 cysts of G. rostochiensis were detected in several seed potato fields. These results indicate the urgent need for the application of further control
measures to determine the presence and distribution of PCN in ware and seed potato lands in Croatia, in order to prevent the
spread of PCN to non-infested areas. Integrated management strategies, neglected until 2001, have now been implemented and
will prevent the build-up of infestation and replace the previous practices of monoculture, the use of short rotations and
growing susceptible cultivars. 相似文献
108.
Rostislav Zemek Miroslava Kurowská Ludmila Kameníková Gabriela Zemková Rovenská Jiří Havel František Reindl 《Journal of pest science》2005,78(2):115-116
Caraway (Carum carvi L.) belongs to the traditional crops which have been grown in Bohemia since the end of the 19th century. Depressaria daucella (Denis and Schiffermüller) and Aceria carvi Nal. are two main pests of caraway in the Czech Republic. The latter becomes a serious problem in major caraway-growing areas. So far, no effective method for its control is known. The aim of this paper is to describe the phenology of symptoms of A. carvi infestation and damage caused by this pest. Our observation revealed that although A. carvi overwinters hidden within leaves of young caraway plants, the first symptoms are usually not visible before the start of flowering. Though the initial density of the pest is low, the mite population multiplies during the season when the pest attacks plant tissues and causes development of galls on leaves and flowers. Comparison of healthy plants and plants infested by A. carvi showed that infested plants had significantly more umbels but produced far fewer seeds, and the yield of caraway was thus substantially decreased. Recommendations for crop management methods to suppress the pest are given.Electronic Supplementary Material Supplementary material is available for this article at 相似文献
109.
Isabella Børja Jan Svĕtlík Valeriy Nadezhdin Jan Čermák Sabine Rosner Nadezhda Nadezhdina 《Scandinavian Journal of Forest Research》2016,31(5):450-457
Top dieback of Norway spruce (Picea abies), triggered by drought in 2004–2006, has been observed in Southeast Norway and trees died within four years after appearance of the first symptoms. The aim of our study was to use sap flux measurements as a diagnostic method for assessment of tree vitality. We used the heat field deformation method to monitor the sap flux density (SFD) in four pairs of healthy and declining trees in situ. To provide retrospective information on hydraulic performance of the trees we took samples for wood anatomical analysis. After felling the trees we used the modified differential translucence method (MDT) as a proxy for the SFD measurements. Healthy trees had three times higher SFD values as declining trees. In some healthy trees we detected decreasing SFD with time. The MDT method agreed with the SFD measurements. In conclusion, we detected sap flux dysfunction in declining trees and showed that the SFD reduction may occur during a short period, prior to occurrence of any visual symptoms. We suggest incorporating the SFD measurements into the repertoire of diagnostic tools in forest pathology. 相似文献
110.
A simulation model of the flight activity ofCydia funebrana was constructed on the basis of data on male captures in pheromone traps placed in a plum orchard in Central Bohemia in 1988 to 1990. The model was verified from 1991 to 1993 as a method of predicting the course of the emergence flight activity of particular generations in dependence on degree day values. The nonlinear model based on Richards' transformation was more suitable for the simulation than the linear one based on probit transformation. A technique has been proposed to use the model ofC. funebrana flight activity for optimal timing of ovicide applications based on fenoxycarb and diflubenzuron in systems of integrated pest management in plum orchards.With 3 figures and 4 tables 相似文献