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481.
Habib Abbasipour Abdolhossein Taghavi Fahimeh Rastegar Edward A. Ueckermann 《Archives Of Phytopathology And Plant Protection》2013,46(12):1439-1448
Predator mites of Phytoseiidae family are among the most important biocontrol agents in the world. These beneficial mites are considered as natural enemies of many pests and herbivore mites, and can feed on different growth stages of pests (egg, larva or nymph). Five species of Phytoseiidae mites were found during a survey conducted on tea plants, Camellia sinensis (Theaceae), in the Mazandaran and Guilan Provinces in the north of Iran, on the coast of the Caspian Sea, the major tea-growing region of Iran. Some of these species are recorded for the first time in tea gardens of Iran. 相似文献
482.
Worker honey bees from genetic strains selected for being resistant (R) or susceptible (S) to tracheal mites typically show
large differences in infestation in field colonies and in bioassays that involve controlled exposure to infested bees. We
used bioassays exposing newly emerged individuals to infested workers to compare the propensity for tracheal mites to infest
queens, drones and workers from R and S colonies. In tests with queens, newly emerged R and S queens were either simultaneously
confined in infested colonies (n = 95 and 87 respectively), or individually caged with groups of 5–20 infested workers (n = 119 and 115 respectively). Mite prevalence (percentage of individuals infested) and abundance (foundress mites per individual)
after 4–6 days did not differ between R and S queens. In another test, five newly emerged drones and workers from both an
R and an S colony, and a queen of one of the two strains, were caged in each of 38 cages with 20 g of workers infested at
60–96% prevalence. Infestations of the R queens (n = 17) and S queens (n = 19) did not differ significantly, but R workers had half the mite abundance of S workers, while R drones received about
a third more migrating mites than S drones. In tests to evaluate possible mechanisms, removal of one mesothoracic leg from
R and S workers resulted in 2- to 10-fold increase in mite abundance on the treated side, but excising legs did not affect
infestation of the corresponding tracheae in drones. This suggests that differences in infestation between R and S workers,
but not drones, are largely determined by their ability to remove mites through autogrooming. If autogrooming is the primary
mechanism of colony resistance to tracheal mites, selection for resistance to tracheal mites using infestation of hemizygous
drones may be inefficient.
*The U.S. Government’s right ot retain a non-exclusive, royalty-free licence in and to any copyright is acknowledged. 相似文献
483.
Two types are known in the Kanzawa spider mite, Tetranychus kanzawai (K and T; see Gotoh et al., 1999), which differ in host range and have a unidirectional incompatibility. Prior to DNA analyzes, crossing between females of a known K type and males of each of 17 strains collected in Japan showed that six of the strains were of the K type, five were the T type and the rest consisted of a mixture of the two types. In order to elucidate the genetic diversity and phylogenetic relationship of T. kanzawai in Japan, we analyzed the DNA sequences of two regions – the internal transcribed spacer 1 (ITS1) of the nuclear ribosomal DNA (rDNA) and a fragment of the cytochrome oxidase subunit I gene (COI) of mitochondrial DNA – using 11 strains (six K-type strains and five T-type strains). Base substitutions were detected on 25 sites of COI (375bp) and 19 sites of ITS1 (486bp), resulting in eight and 17 haplotypes, respectively. The phylogenetic trees constructed using the DNA sequences failed to clearly distinguish between the two types. The results suggested that the T type was derived from the K type. 相似文献
484.
Non-infested, young adult honey bees (Apis mellifera L.) of two stocks were exposed to tracheal mites (Acarapis woodi (Rennie)) in infested colonies to determine how divergent levels of susceptibility in host bees differentially affect components of the mite life history. Test bees were retrieved after exposure and dissected to determine whether resistance is founded on the reduced success of gravid female (foundress) mites to enter the host tracheae, on the suppressed reproduction by foundress mites once established in host tracheae or on both. Cohorts of 30–60 bees from each of ten resistant colonies and eight susceptible colonies were tested in eight trials (three to five colonies per stock per trial) having exposure durations of 4, 9 or 21 days. The principal results were that lower percentages of resistant bees than of susceptible bees routinely became infested by foundress mites, individual infested susceptible bees often had more foundress mites than individual infested resistant bees did and mite fecundity was similar in both host types. The infestation percentage results corresponded well with similar results from a prior field test of these stocks and, thus, suggest that the bioassay is useful for assessing honey bee resistance to A. woodi. 相似文献
485.
486.
Oral administration of Lactobacillus strains from Kimchi inhibits atopic dermatitis in NC / Nga mice
Won TJ Kim B Lim YT Song DS Park SY Park ES Lee DI Hwang KW 《Journal of applied microbiology》2011,110(5):1195-1202
Aims: Atopic dermatitis (AD) is marked by elevated levels of immunoglobulin E and skin lesions such as oedema and haemorrhage. Kimchi is a Korean fermented food that contains beneficial bacteria for human health. In this study, Lactobacillus plantarum CJLP55, CJLP56, CJLP133 and CJLP136 isolated from Kimchi were investigated for their capacity to inhibit AD. Methods and Results: The three strains, CJLP55, CJLP133 and CJLP136, suppressed AD‐like skin lesions, high serum IgE levels and epidermal thickening. The three strains diminished the accumulation of eosinophils and mast cells into topical inflammatory sites and the enlargement of axillary lymph nodes, which are responsible for the dorsal dermatitis. CJLP55, CJLP133 and CJLP136 decreased production of type 2 cytokines such as IL‐4 and IL‐5 in lymph node cell culture. CJLP133 and CJLP136 increased IFN‐γ secretion, while CJLP55 enhanced IL‐10 production. Conclusions: The three strains isolated from Kimchi suppress house‐dust mite‐induced dermatitis in NC/Nga mouse, a representative animal model of human AD. Significance and Impact of the Study: These findings suggest that lactobacilli isolated from Kimchi inhibit AD, probably by altering the balance of Th1/Th2 ratio or inducing IL‐10 production. 相似文献
487.
The carmine spider mite, Tetranychus cinnabarinus (Boisduval) and the twospotted spider mite, Tetranychus urticae Koch, are serious pests of strawberries and many other horticultural crops. Control of these pests has been heavily dependent upon chemical acaricides. Objectives of this study were to determine the resistance status of these two pest species to commonly used acaricides on strawberries in a year‐round intensive horticultural production region. LC90 of abamectin for adult carmine spider mites was 4% whereas that for adult twospotted spider mites was 24% of the top label rate. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 0.5%, 0.5%, 1.4% and 83% of their respective highest label rates for carmine spider mite eggs, 0.7%, 2.7%, 12.1% and 347% of their respective highest label rates for the nymphs. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 4.6%, 11.1%, 310% and 62% of their respective highest label rates for twospotted spider mite eggs, 3%, 13%, 432,214% and 15% of their respective highest label rates for the nymphs. Our results suggest that T. cinnabarinus have developed resistance to bifenazate and that the T. urticae have developed resistance to hexythiazox. These results strongly emphasize the need to develop resistance management strategies in the region. 相似文献
488.
Osakabe M Hinomoto N Toda S Komazaki S Goka K 《Experimental & applied acarology》2000,24(5-6):385-395
Genetic markers were searched using PCR with 40 kinds of decanucleotide primers to investigate DNA polymorphism in Panonychuscitri. A region consisting of a variable number of CT tandem repeats (microsatellite) was found in a fragment amplified with the OPB10 primer. The microsatellite differed in size by ca. 100bp among several P. citri populations screened and was derived from at least seven alleles. This region was characteristic of P. mori and P. osmanthi, but was lacking in P. ulmi. The flanking regions were highly conserved among these species. 相似文献
489.
There are an estimated 0.5–1 million mite species on earth. Among the many mites that are known to affect humans and animals, only a subset are parasitic but these can cause significant disease. We aim here to provide an overview of the most recent work in this field in order to identify common biological features of these parasites and to inform common strategies for future research. There is a critical need for diagnostic tools to allow for better surveillance and for drugs tailored specifically to the respective parasites. Multi-‘omics’ approaches represent a logical and timely strategy to identify the appropriate mite molecules. Recent advances in sequencing technology enable us to generate de novo genome sequence data, even from limited DNA resources. Consequently, the field of mite genomics has recently emerged and will now rapidly expand, which is a particular advantage for parasitic mites that cannot be cultured in vitro. Investigations of the microbiota associated with mites will elucidate the link between parasites and pathogens, and define the role of the mite in transmission and pathogenesis. The databases generated will provide the crucial knowledge essential to design novel diagnostic tools, control measures, prophylaxes, drugs and immunotherapies against the mites and associated secondary infections. 相似文献
490.
Negin Ghazazani Mahmoud Lotfi Ali Asghar Talebi 《Archives Of Phytopathology And Plant Protection》2013,46(8):971-979
The effect of two host plant species including eight genotypes of melon (Cucumis melo L.) and four genotypes of cucumber (Cucumis sativus L.) was studied on reproductive parameters: life expectancy and mortality of Tetranychus urticae (Koch) at 25?±?1?°C, 60?±?5% rh and a photoperiod of 16L:8D hours. The results indicated that the highest value of the gross fecundity rate of T. urticae was 96.72?±?16.70 (eggs/female) on Mir sultan and the lowest value was 14.33?±?0.88 on Ananasi. The maximum value of gross fertility rate (41.55?±?4.79) was recorded on Sultan, while the minimum value (1.38?±?0.08) was recorded on Ananasi. The net fecundity rate was varied from 0.47?±?0.09 on Ananasi to 23.53?±?3.96 eggs/female on Sultan. The net fertility rate was 12.96?±?2.18 on Sultan and 0.04?±?0.009 on Ananasi, which was the maximum and minimum values, respectively. The range of gross hatch rate on different melon and cucumber genotypes was 9.67% on Ananasi to 72.46% on Super sultan. The cohort reared on Super sultan had the highest mean eggs per day and those on Shah abadi had the lowest mean eggs per day. In addition, the mite demonstrated the maximum value of mean fertile eggs per day with the amount of 1.66?±?0.19 eggs/female when fed on Sultan, and Ananasi demonstrated the minimum value (0.09?±?0.005). The life expectancy of one-day-old adults of T. urticae was estimated to be 16?days on Garmak Isfahan and 26.62 days on Mir sultan which is the maximum and minimum values, respectively. Furthermore, the highest mortality percentage of immature stages of T. urticae was recorded on Ananasi and the lowest was recorded on Super sultan. Comparison of the data collected in this study revealed that the mites had considerably better performance on cucumber genotypes than melon genotypes, so we can assume that cucumber is the preferable host species for T. urticae. The use of preferable and resistant host plants is helpful in crop rotation and it will be one of the beneficial strategies to integrated pest management programmes. 相似文献