Prevalence of arthropod antibodies in Korean patients with allergic rhinitis.

Arthropod antigens are main causative agents which induce allergic responses in humans. However, little information is known about the prevalence of specific arthropod allergens in Koreans with allergic diseases. The current study was designed to determine the positive rates of arthropod antibodies by the Korean inhalant panel of MAST-CLA. One hundred sixty patients, who were diagnosed with allergic rhinitis from an out-patient center at the Soonchunhyang University Chunan Hospital, were studied between August 1998 to July 2000. The overall positive rate, at least more than one specific antibody of arthropods such as Dermatophagoides farinae (Df), Dermatophagoides pteronyssinus (Dp), and cockroach mix (Cm), was 46.9%. Each positive rate of Df, Dp, and Cm was 45.0%, 43.1%, and 8.8%, respectively. A significant agreement among arthropod allergens was observed (Df and Dp: 95.6%, Kappa = 0.911, P < 0.001). Our data supported the fact that arthropods were the most common allergens in Korean patients with allergic rhinitis; however, the MAST-CLA should be modified to increase specificity of arthropod allergens.     

Biodiversity and distribution of water mites (Acari, Hydrachnidia) in spring habitats

1. The distribution, species richness and ecology of spring‐dwelling water mites in Italy were investigated with the aim to better elucidate the role of spring habitats to sustain high levels of biodiversity and their contribution to freshwater biodiversity at a local and regional scale. 2. More than 300 springs in different geographic areas (Alps, Central and Southern Apennines, Sicily and Sardinia), were examined with a total of 163 water mite species recorded. 3. Species richness in each area ranged from 33 species on Sardinia to 77 on Sicily. The highest diversity was found in the Gran Sasso (Central Apennines). The proportion of crenobionts (species strictly bound to this type of habitat) exceeded 50% in almost all the areas investigated. 4. A diverse (up to 20 species per spring) and highly specialised mite fauna was observed in undisturbed rheocrenes and in natural springs of intermediate typology (rheohelocrenes and rheopsammocrenes). In springs subjected to human impacts (pasture, deforestation, alteration and transformation of spring sources) species richness declined and crenobionts were replaced by unspecialised crenoxenes. 5. The zoogeographic importance of spring habitats is confirmed by the presence of 18 endemic species and by members of genera with an interesting disjunct and relict distribution. 6. A comparison with other geographic areas suggests that springs contain a significant fraction of the total number of species found in freshwater habitats and may contribute almost one third of regional freshwater biodiversity. The presence of endemic crenobionts and rare taxa highlights the importance of these habitats in maintaining high levels of biodiversity as well as their contribution to a better understanding of biodiversity patterns in freshwaters.     

Diversity and biogeography of southern African intertidal Acari

Abstract Aim The aims were (1) to describe the diversity and geographical distribution of the intertidal mite fauna of southern Africa, and (2) to show how species richness, endemism and geographical patterns of this fauna (comprising taxa of variable terrestrial ancestry) compare with typically marine faunas. Location and methods To assess intertidal mite diversity and endemism, records (published and unpublished) were compiled for a variety of habitats (mainly rocky shores and mangroves), between Swakopmund (Namibia) and Inhambane (Mozambique). The geographical study was based on a dedicated sampling programme from rocky shores, at nine localities between Elandsbaai (on the west coast) and St Lucia (on the east coast). Results Eighty‐two species of marine mite, from thirty‐three genera, are currently known from southern Africa. The majority belong to the earlier marine ancestral Halacaridae (forty‐eight species), with the Ameronothroidea and Hyadesiidae collectively comprising seventeen species. In constituting three faunistic provinces, corresponding with the west (Atlantic), south and east coast (Indian) regions, the mite fauna conforms with trends for the southern African marine fauna in general. Species richness was greatest in the southern province, which deviates from the general pattern of increase from west to east, but is similar to that of some invertebrate taxonomic groups. Conclusions Despite their relatively recent marine connections, marine mites show typical geographical distributions, comparable with those of other rocky‐shore biota in southern Africa. The marine faunistic provinces are ‘insular’ and apparently remain largely intact, across taxonomic groups and with increased taxonomic resolution.     

Immune expression in a damselfly is related to time of season, not to fluctuating asymmetry or host size

1. Variation in immune responsiveness within and among species is the subject of the emerging field of ecological immunology. The work reported here showed that individuals of Lestes forcipatus Rambur differ in their likelihood of mounting immune responses, and in the magnitude of those responses, against a generalist ectoparasite, the water mite Arrenurus planus Marshall. 2. Immune responses took the form of melanotic encapsulation of mite feeding tubes, occurred in the few days after host emergence, and resulted in mites dying without engorging. Such immune responses were more probable and stronger for hosts sampled later rather than earlier in the season. Such responses may act as selection affecting seasonal patterns of egg hatching and larval abundance of mites. 3. Contrary to expectation, metrics of host size (wing length) and wing cell fluctuating asymmetry were not related to the likelihood of immune responses. 4. The importance of season on immune expression of insects has not been explored in detail. These results suggest possible trade‐offs in allocation of melanin (or its precursors) to maturation versus immunity, and indicate the need for studies on the synergistic effects of weather and parasitism on host species that use melanotic encapsulation to combat parasites and pathogens.     

Combined versus Single Species Release of Predaceous Mites: Predator–Predator Interactions and Pest Suppression

Interactions such as competition, intraguild predation (IGP), and cannibalism affect the development and coexistence of predator populations and can have significance for biological control of commonly exploited pest organisms. We studied the consequences of combined versus single release of two predaceous mite species (Phytoseiidae), with differing degrees of diet specialization, on their population dynamics and the suppression of the carmine spider mite, Tetranychus cinnabarinus Boisduval (Tetranychidae), on greenhouse-grown gerbera. Population growth of the specialist predator Phytoseiulus persimilis Athias-Henriot was greater and population decline steeper when released in combination with the generalist Neoseiulus californicus McGregor than when released alone. In contrast, the N. californicus population grew and declined more gradually when released in combination with P. persimilis, compared to the single species release. The differential impact on each other's population dynamics can be primarily attributed to contrasting properties in competition, IGP, and cannibalism. At the same overall predator density and as long as prey was abundant, the specialist P. persimilis was more strongly affected by intraspecific competition than by interspecific competition with the generalist N. californicus. In contrast, interspecific competition with P. persimilis had a greater impact on N. californicus than intraspecific competition. After prey depletion, the generalist predator N. californicus was more likely to engage in IGP than was the specialist predator P. persimilis. Overall, the study demonstrates that prey specificity has significance for the quality and intensity of predator–predator interactions and indicates potential implications for biological control of spider mites. All predator releases (i.e., either species alone and both species in combination) resulted in reduction of the spider mite population to zero density. Individual release of the specialist P. persimilis led to the most rapid spider mite suppression. Nonetheless, in perennial greenhouse-grown crops P. persimilis and N. californicus could have complementary effects and a combination of the two predators could enhance long-term biological control of spider mites. The potential risks and benefits associated with the release of both species are discussed.     

强度石漠化区不同植被修复模式下土壤螨类群落差异

石漠化治理区不同植被修复模式下的土壤螨类群落差异反映了生态系统的恢复状况,可籍以反映石漠化治理的生态效果。2014年1月、4月、8月和10月,对贵州花江喀斯特峡谷区顶坛小流域强度石漠化区域的"花椒"、"金银花"、"花椒+金银花"3种植被修复生境的土壤螨类进行了调查,共捕获土壤螨类1372头,隶属3目55科89属。采用类群(属)数、个体数量、个体密度、多样性指数(H')、丰富度指数(SR)、均匀性指数(J)、相似性指数(CN)、捕食性螨类成熟度指数(MI)和甲螨MGP类群等参数对土壤螨类群落差异进行了表征。结果显示,花椒林拥有较丰富的螨类属,金银花林拥有较高的的个体数量和个体密度。不同模式下的科、属类群组成呈现差异;属数、个体数量存在一定的季节差异,花椒林的螨类属数、金银花林的螨类个体数量和个体密度呈现一定的表聚性;群落多样性大多存在季节差异;捕食性革螨以r选择型为主,甲螨主要为O型和M型。研究表明,强度石漠化在不同植被修复模式下,土壤螨类生物生态类群存在差异,土壤生态系统仍处于修复之中,其中螨类优势属、具有典型生物学与生态学特性差异的螨类类群对石漠化治理的生态效果具有重要的指示作用。     

Conflict between antipredator and antiparasite behaviour in larval damselflies

 Larval damselflies resist infestation by parasitic larval mites by exhibiting behaviours such as grooming, crawling, swimming, and striking at host-seeking mites. Larval damselflies are known to increase time spent in these behaviours in the presence of mites but reduce time spent in these behaviours in the presence of fish predators. The presence of both fish and larval mites presents an obvious conflict: a larval damselfly may actively avoid parasitism by mites, thus increasing its risk of predation, or it may reduce its activity when fish are present, thus increasing its risk of parasitism. We analysed the behaviour of larval Ischnura verticalis in an experiment where we crossed presence and absence of fish with presence and absence of larval mites. Presence of mites induced a large increase in activity of larval I. verticalis but fish had no effect and there were no interpretable interactions between effects of mites and fish. Subsequent experiments indicated that larval I. verticalis in the presence of both mites and fish were more likely to be attacked and killed by fish than those exposed only to fish. The high activity level of I. verticalis larvae in the presence of both fish and mites may suggest that costs of parasitism are high, or that under field conditions it is rare for larvae to be in the immediate presence of both fish predators and potentially parasitic mites. Received: 28 March 1996 / Accepted: 6 September 1996     

Factors affecting the presence of Typhlodromusspp. (Acarina: Phytoseiidae) in the calyx cavities of apple fruits and implications for integrated pest management

Predatory mites of the family Phytoseiidae include several species of importance as biological control agents of phytophagous mites in various crops including apples. We report on the post-harvest presence of the motiles of two species, Typhlodromus occidentalis and Typhlodromus pyri, in the calyx cavities of apple fruits of three cultivars. The mean numbers of motiles per fruit were as high as 6.10. The phytoseiid densities were lowest in cv. Bonza and tended to be greater in samples taken in late autumn, particularly in cv. Red Delicious. No significant effect (p > 0.05) was observed for different insecticide treatments. Phytoseiids remained present within fruits of cv. Granny Smith left on the orchard floor in winter. Together with an observed reduction in the numbers of T. occidentalis in the early spring, this suggests that fruits constitute an overwintering refuge. The findings are discussed in relation to the implications for biological control, in particular the minimization of the removal of natural enemies from orchards. This revised version was published online in November 2006 with corrections to the Cover Date.     

ISOLATION OF RICKETTSIA TSUTSUGAMUSHI FROM TROMBICULID MITES (ACARI:TROMBICULIDAE) IN FEIXIAN COUNTY, SHANDONG PROVINCE, CHINA

Abstract  Investigations on trombiculid mites and isolation of Rickettsia tsutsugamushi therefrom were carried out in Feixian County, Shandong Province. A total of 11 762 trombiculid mites, consisting of 5 species from two genera, were collected from 352 rodents (including 247 Apodemus agrarius , 80 Cricetulus triton , 23 Rattus noruegicus , 2 Crocidura suaveolens ), and Walchia pacifica was the most predominant (36.73%), followed by Leptotrombididium linhuaikonense (24.04%), L. scutellare (21.65%), L. palpale (13. 57%), and L. taishanium (3. 96%). L. scutellare was found from September to December with a remarkable peak in November, whereas L. palpale occurred from October to April (the second year) with peak in December. L. linhuaikonense was found from May to November, with peak in August. W. pacifica appeared from April to December with peak in July. R. tsutsugamushi was isolated from L. scutellare, L. palpale, L. linhuaikonense and W. pacifica . The main serotypes of R. tsutsugamushi isolated from the chigger mites were of the Gilliam type, but Karp type also existed in L. linhuaikonense . These results indicate that the surveyed area has a high probability of occurrence of tsutsugamushi disease, and L. scutellare, L. palpale, L. linhuaikonense and W. pacifica may serve as the vectors in this area. It is suggested that L. scutellare is the most important vector which has caused the endemic of this disease in Feixian County.