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83.
云南西部不同生境区域革螨群落的模糊聚类分析 总被引:8,自引:0,他引:8
云南西部10个不同生境区域小兽体表革螨群落经用模糊聚类分析,归并为4种群落类型:华南区室内生境型、华南区室外农耕地生境型、西南区室内生境型及西南区室外农耕地生境型。研究表明,生境的不同或在动物地理上位置的不同导致了革螨群落的差异。 相似文献
84.
Marília Lara Peixoto Leda Gonçalves Fernandes Matheus Araújo Cardoso Carvalho Milena Leite de Oliveira André Rodrigues dos Reis 《Biocontrol Science and Technology》2017,27(3):424-432
Agro-ecological diversification may increase natural biodiversity and decrease environmental impacts caused by the intensification of management practices, especially with respect to pest control. This study aimed to evaluate mite populations from surveys in commercial coffee (Coffea arabica) orchards managed in different ways. Four different cropping systems were compared: a conventional system (CS), non-pesticide system (NPS), organic system (OS) and organic agroforestry system (OAS). Mite samples were taken from 24 coffee plantations (n?=?6 for each management strategy). Six leaves per plant were collected from five sampling sites totalling 30 leaves from each plantation. Mites were removed from individual leaves, counted and identified to family level. Amongst the predatory mites, two families were detected; the Phytoseiidae was the most abundant family while the Stigmaeidae, generalist predatory mites, were only found in two management systems (NPS and AOS). Of the two families of phytophagous mites, the family Tenuipalpidae was the most abundant, but rarely found in AOS. The other phytophagous family, Tetranychidae, was less abundant in coffee crops than Tenuipalpidae, but the most abundant phytophagous family in CS. Understanding the relationship between mite populations and management practices can aid in choice of spraying strategies for different coffee management systems. 相似文献
85.
长期以来,螨类主要依靠其形态特征进行系统学研究。DNA标记是指能反映生物个体或物种间基因组中某种差异特征的DNA片段。近年来,DNA标记技术在螨类系统学研究中得到越来越广泛的应用。本文综述了随机扩增多态性RAPD、限制性内切酶片段长度多态性RFLP、微卫星SSR、核酸序列扩增、扩增片段长度多态性AFLP和直接扩增片段长度多态性DALP等6种DNA标记技术在螨类系统学研究中的应用现状及前景。 相似文献
86.
The spider mites belonging to the genus Stigmaeopsis constructextremely dense oval woven roofs (web-nests) over depressionson the lower surface of host leaves and are known to have akind of sociality. The four species that occur on bamboo plantsin Japan show different nest areas. The nest area of Stigmaeopsislongus is the largest, followed by that of S. celarius, S. takahashii,and S. saharai in decreasing order. Smaller nests effectivelyprevent adults of several predator mite species from intruding.We hypothesized that variation in nest size reflects differentanti-intruder adaptations of this mite group in relation totheir sociality. The larger nest makers may adopt an alternativeanti-intruder strategy, namely, counterattack by a large group,so as to compensate for the disadvantage of large nests. S.longus and S. celarius adults effectively defended their largenests against potential predators, and the effects of nest defenseincreased with the number of individuals in a nest. S. takahashiiand S. saharai revealed no counterattack effect. Counterattackabilities that increase with the adult density, and thus, socialitymay compensate for the vulnerability of larger nests. 相似文献
87.
The aim of the present study was to identify food sources of bark-living oribatid mites to investigate if trophic niche differentiation
contributes to the diversity of bark living Oribatida. We measured the natural variation in stable isotope ratios (15N/14N, 13C/12C) in oribatid mites from the bark of oak (Quercus robur), beech (Fagus sylvatica), spruce (Picea abies) and pine (Pinus sylvestris) trees and their potential food sources, i.e., the covering vegetation of the bark (bryophytes, lichens, algae, fungi). As
a baseline for calibration the stable isotope signatures of the bark of the four tree species were measured and set to zero.
Oribatid mite stable isotope ratios spanned over a range of about 13 δ units for 15N and about 7 δ units for 13C suggesting that they span over about three trophic levels. Different stable isotope signatures indicate that bark living
oribatid mites feed on different food sources, i.e., occupy distinct trophic niches. After calibration stable isotope signatures
of respective oribatid mite species of the four tree species were similar indicating close association of oribatid mites with
the corticolous cover as food source. Overall, the results support the hypothesis that trophic niche differentiation of bark
living oribatid mites contributes to the high diversity of the group. 相似文献
88.
Peter Schausberger 《Experimental & applied acarology》1999,23(5):389-398
The predation preference of singly caged adult females and nymphs of Typhlodromus pyri and Kampimodromus aberrans for con- or heterospecific immature stages as prey was tested in the laboratory. Both polyphagous predatory mite species have been previously shown to interact directly through predation on each other. The present study demonstrated that the adult females of T. pyri and K. aberrans are able to discriminate between con- and heterospecific larvae and protonymphs and that they prefer to prey upon heterospecifics when given the choice. Hunger did not reduce the propensity of the females to prefer heterospecifics over conspecifics. For proto-and deutonymphs the trends followed the results obtained with the adult females, but the preference for heterospecifics was not distinct enough to be significant. In competitive situations reciprocal predation may be a crucial mechanism in the interaction of polyphagous phytoseiid species and may contribute significantly to population persistence. The results are discussed with regard to possible associations between the ability to discriminate con- and heterospecifics and the type of feeding specialization (generalists versus specialists). 相似文献
89.
Histiostoma feroniarum, like other histiostomatid mites, possesses peculiar ring organs that are visible under the light microscope as ventrally located, characteristic rings of sclerotized cuticle. The ring organ is composed of three elements: a disc of modified cuticle, ring organ cells located underneath the disc, and an "empty" chamber frequently visible between the cuticular disc and the cells. The cuticle of the disc is not perforated and differs from the surrounding unmodified cuticle as revealed by special staining developed for light microscopy and by electron microscopy. The ring organ cells show a polarity, with a practically smooth apical surface and an extremely folded basal membrane. The basal invaginations reach the apical cell portion, where they form tubular canaliculi distributed beneath the apical cell membrane. The cytoplasm contains many mitochondria, which are usually in contact with the cell membrane invaginations. Structurally, the ring organ cells closely resemble the transport cells described in osmoregulatory organs both in water-inhabiting and terrestrial arthropods. Thus, our results support earlier suggestions of an osmoregulatory function performed by sclerotized rings (=ring organs), as an adaptation to aqueous environments. A possible homology with similar organs of other mites is discussed. 相似文献
90.
Being minute in size, eriophyoid mites can reach places that are small enough to be inaccessible to their predators. The coconut
mite, Aceria guerreronis, is a typical example; it finds partial refuge under the perianth of the coconut fruit. However, some predators can move
under the perianth of the coconut fruits and attack the coconut mite. In Sri Lanka, the phytoseiid mite Neoseiulus baraki, is the most common predatory mite found in association with the coconut mite. The cross-diameter of this predatory mite
is c. 3 times larger than that of the coconut mite. Nevertheless, taking this predator’s flat body and elongated idiosoma into
account, it is—relative to many other phytoseiid mites—better able to reach the narrow space under the perianth of infested
coconut fruits. On uninfested coconut fruits, however, they are hardly ever observed under the perianth. Prompted by earlier
work on the accessibility of tulip bulbs to another eriophyoid mite and its predators, we hypothesized that the structure
of the coconut fruit perianth is changed in response to damage by eriophyoid mites and as a result predatory mites are better
able to enter under the perianth of infested coconut fruits. This was tested in an experiment where we measured the gap between
the rim of the perianth and the coconut fruit surface in three cultivars (‘Sri Lanka Tall’, ‘Sri Lanka Dwarf Green’ and ‘Sri
Lanka Dwarf Green × Sri Lanka Tall’ hybrid) that are cultivated extensively in Sri Lanka. It was found that the perianth-fruit
gap in uninfested coconut fruits was significantly different between cultivars: the cultivar ‘Sri Lanka Dwarf Green’ with
its smaller and more elongated coconut fruits had a larger perianth-fruit gap. In the uninfested coconut fruits this gap was
large enough for the coconut mite to creep under the perianth, yet too small for its predator N. baraki. However, when the coconut fruits were infested by coconut mites, the perianth-rim-fruit gap was not different among cultivars
and had increased to such an extent that the space under the perianth became accessible to the predatory mites. 相似文献