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61.
Tereza Zichová František Kocourek Jaroslav Salava Kateřina Nad'ová Jitka Stará 《Pest management science》2010,66(8):853-860
BACKGROUND: Pyrethroids and organophosphates are the most frequently used insecticides for Colorado potato beetle, Leptinotarsa decemlineata (Say), control in the Czech Republic. Based on molecular methods, organophosphate and pyrethroid resistance alleles have been detected in samples from three sites. The accuracy of restriction fragment length polymorphism (RFLP) and bidirectional polymerase chain reaction amplification of specific alleles (Bi‐PASA) for detection of resistance alleles is compared. RESULTS: Leptinotarsa decemlineata from three sites showed higher frequencies of resistance alleles to organophosphates than to pyrethroids. The rates of occurrence of individuals homozygous resistant (RR) to pyrethroids ranged from 20.0 to 22.9%, while the rates of occurrence of individuals RR to organophosphates ranged from 52.9 to 66.7%. The incidences of individuals with resistance alleles to both organophosphates and pyrethroids ranged from 8.6 to 13.6%. No relationship was found between incidence of the pyrethroid resistance allele and site, while incidence of the organophosphate resistance allele differed significantly according to site. CONCLUSION: Both RFLP and Bi‐PASA were suitable for detecting resistance alleles to pyrethroids, and in most cases also for detecting resistance alleles to organophosphates. In contrast to Bi‐PASA, RFLP was also suitable for samples with lower DNA quality when testing for the resistance allele to pyrethroids. On the other hand, RFLP was not as accurate as Bi‐PASA in detection of the organophosphate resistance allele. Copyright © 2010 Society of Chemical Industry 相似文献
62.
63.
Adults of Cephalcia lariciphila emerge and start their activity at Vetrny Jenikov village (Czech Republic) during mid-April. First specimens were collected
from Malaise traps at the same time as from emergence traps. Last specimens flew at the beginning of May or even the beginning
of June. Adult occurrence typically lasted about 20 (–30) days. One Malaise trap and five yellow sticky boards were placed
on three plots, and sawflies were collected at 1 hour intervals in two two-day periods. The variables with the best explanatory
power for activity of imagos were temperature in interaction with humidity. Sawflies were most active at 16°C with 20% air
humidity and numbers caught decreased steeply up to 0°C and 80% air humidity. The daily flight activity began at 10 a.m. and
ended after 5 p.m. Both methods, the Malaise traps and the yellow sticky boards, should be used in forest practices from the
middle of April. 相似文献
64.
- 1. Crucian carp Carassius carassius, which is native to south‐east England, has received little previous study in Britain but is threatened by introductions of goldfish Carassius auratus through hybridization and by frequent mis‐identification of brown goldfish as crucian carp. The present study provides the first data on back‐calculated growth, morphology and age‐at‐maturity of crucian carp in Britain.
- 2. The youngest mature crucian were female (age 2+), the smallest mature crucian were male (age 3+), with almost all fish mature at age 3+. Sex dimorphism in back‐calculated standard length at age was not observed except at age 2+ (juveniles longest). Shifts in morphological characters often associated with maturation (dorsal and ventral fin length, dorsal and anal fin depth, pre‐dorsal distance, body width) were observed between ages 4+ and 7+, which (in contrast to the relatively abrupt shift in maturity) suggests that age and size at maturation may not reflect the size and age of active (i.e. real) spawning.
- 3. Back‐calculated standard lengths at age for crucian carp were intermediate relative to other European populations, indicating that environmental conditions in England appear to be well suited to the species despite being at the westernmost extent of the species' native European range. The management of ornamental ponds specifically for crucian carp is discussed.
65.
Food selection and internal processing in Archegozetes longisetosus (Acari: Oribatida) 总被引:1,自引:0,他引:1
The nutritional biology of the oribatid mite Archegozetes longisetosus Aoki was examined using a control (starvation) and four types of food: Protococcus sp. algae from tree bark, two fungi—Stachybothrys sp. and Alternaria sp.—and filter paper. Direct observations, histology, enzymology and plating techniques were employed to record contact with food, contents and structure of the alimentary tract, presence and viability of bacterial microorganisms inside the mite body, and chitinase and cellulase activity of mite homogenates. Algae were highly palatable, resulting in high apocrine secretion and guts that were continuously full. Initially there was no evidence of chitinase or cellulase production. Chitinase activity started after 10 days, probably due to consumption of fungi that invaded the algal cover, and correlated with the presence of chitinolytic bacteria (Serratia rubidea) in the mite homogenate. Alternaria was grazed intensively, but cell walls of spores and hyphae remained intact and no chitinase was detected suggesting that only cell contents were enzymatically digested. Stachybothrys sp. was rejected as food. The bacterium Alcaligenes faecalis was dominant in homogenates in each of the treatments, but under starvation Achromobacter xylosoxidans became co-dominant. Cellulase activity was not detected in any treatment, but strong chitinase activity was induced with a filter paper (colonized by invasive fungi) diet. Furthermore, bacteria were common in mesenchyme between the internal organs in the filter paper and starvation treatments. 相似文献
66.
Sándor Süle Marie Horká Hana Matoušková Anna Kubesová Jiří Salplachta Jaroslav Horký 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(1):81-89
Tumorigenic and non-tumorigenic strains of Agrobacterium tumefaciens, A. rhizogenes, A.rubi, and A.vitis were examined using capillary isoelectric focusing, phenotypic determinative tests, PCR and fatty acid analysis. The isoelectric
points (pI) of the 40 strains investigated clearly differentiated the strains according to their respective species. The different species
were characterized with the following pI values: A. tumefaciens 2.2, A. rhizogenes 4.0, A. rubi 2.15, and A. vitis 2.6. This differentiation corresponded to the phenotypic, PCR and fatty acid characterizations. Strains with the similar
chromosomal background but different plasmid content, e.g. A.vitis strain S4, and F2/5 gave the same pI values. Strains of Rhizobium species differed from Agrobacterium strains in their pI values. The advantage of capillary isoelectric focusing over the phenotypic determinative tests, PCR and fatty acid analysis
is its speed (15 min), relative simplicity, and the very small amount of chemicals used. This rapid and simple method is a
major improvement over the classical methods of separation of Agrobacterium species and should prove useful for rapid characterization of Agrobacterium-like colonies isolated from plant tumours for epidemiological and generic diversity studies. 相似文献
67.
Majtan J Klaudiny J Bohova J Kohutova L Dzurova M Sediva M Bartosova M Majtan V 《Fitoterapia》2012,83(4):671-677
Methylglyoxal (MGO) is a major antibacterial component of manuka honey. Another antibacterial component found in Revamil honey, peptide defensin1, was not identified in manuka honey. The primary aim of the study was to evaluate the content of defensin1 in honeys of different botanical origins and to investigate a presumed effect of reactive MGO on defensin1 and a dominant protein of honey MRJP1 in manuka honey. Immunoblotting of honey samples showed that defensin1 was a regular but quantitatively variable component of honeys. One of the reasons of varying contents of defensin1 in different honeys seems to be constitutive but varying defensin1 expression in individual honeybees in bee populations that we documented on samples of nurse and forager bees by RT-PCR. Comparative analyses of honeys revealed a size modification of defensin1, MRJP1 and probably also α-glucosidase in manuka honey. We further showed that (i) the treatment of purified defensin1 in solution containing high amount of MGO caused a time-dependent loss of its antibacterial activity and (ii) increasing MGO concentrations in a non-manuka honey were connected with a gradual increase in the molecular weight of MRJP1. Obtained results demonstrate that MGO abrogates the antibacterial activity of defensin1 and modifies MRJP1 in manuka honey. We assume that MGO could also have negative effects on the structure and function of other proteins/peptides in manuka honey, including glucose oxidase, generating hydrogen peroxide. 相似文献
68.
Zelnickova P Kovaru H Pesak S Lojek A Matalova E Ondracek J Kovaru F 《Veterinary immunology and immunopathology》2006,113(3-4):383-391
Developmental changes of functional ability of peripheral blood phagocytes from days 1 to 100 of life were investigated. Luminol enhanced chemiluminiscence was used to establish the ability of phagocytes to produce reactive oxygen species (ROS). Simple superoxide anion production was determined by spectrophotometrical measurement of cytochrome c. Activity of surface aminopeptidase N was assessed by spectrophotometrical measurement of l-alanine-p-nitroanilide. Flow cytometric measurements of CD18 and CD45 expression were performed. The ROS production per 0.5microl of blood did not show any trend; however, the values recalculated per 500 granulocytes had a decreasing course. The most noteworthy increase in production of superoxide anion occurred between days 17 and 26. Activity of aminopeptidase N decreased during the first 4 weeks. Expression of CD18 and CD45 intensively increased from days 1 to 14 with gradual decrease by day 100. Natural immunity develops during the early postnatal life and seems to be influenced by exposure of the organism to environmental antigens. 相似文献
69.
Glycogen deposits were studied in the parenchyma of the oribatid Melanozetes meridianus Sellnick through two years, with respect to food consumption, alimentary tract characteristics and environmental factors. A remarkable peak in the amount of glycogen granules was observed in autumn and early winter, but they were low or absent in spring. The females exhibited a higher density of glycogen granules. 相似文献
70.