• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.179-184
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• 2000

This study was conducted to improve control system of insect pests, especially western flower thrips, Frankliniella occidentalis, and two-spotted spider mites, Tetreanychus urticae, of rose greenhouses. Density of thrips was relatively higher in yellow flowers than in pink or redflowers, while there was no difference in density of two-spotted spider mites by flower colors. In pest control by an automatic monorail sprayer, 89% labor and 18.2% chemical savings, as compared to the conventional high pressure spray method, were achieved without lowering the pest control effectiveness. By using an adhesive agent in combination with acaricide, adhesion of chemical to crops increased by 25% and control effect on two-spotted spider mites increased by 20.5% as compared acaricide spray alone.

• Animal cells and systems
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• v.2 no.4
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• pp.513-520
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• 1998

Though the wandering spiders do not produce webs for prey-catching, they have silk producing apparatus. Among the four kinds of silk glands in the wolf spider, Pardosa astrigera, the ampullate one is the most predominant gland in both sexes, and is composed of three functional parts; excretory duct, storage ampulla and convoluted tail regions. The duct is basically composed of three superposed types of layers which are inner cuticles, monolayered epithelial cells and peripheral connective cells. The electron lucent subcuticles which have the functions of water removal and orientation of silk fibers during polymerization are well developed at the anterior region near the spinneret. Whereas the endocuticles which contain two types of banding patterns at the cross section are developed at the rest of the duct region. The secretory silks are synthesized within the glandular epithelial cells of the tail as secretory granules, and then released to the inner cavity of the storage ampulla by the mechanism of apocrine secretion. Most of these secretory vesicles are originated from the rough endoplasmic reticula of the glandular epithelial cells, whereas no Golgi complexes are found in any of the cells which have been examined.

• Applied Microscopy
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• v.43 no.2
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• pp.65-74
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• 2013

Although the geometrical difference in body position between web-building and wandering spiders could affect the organization of their central nervous system (CNS), however most of our informations about spider's CNS are dependent on those revealed from the wandering spiders. Therefore, this paper describes microstructural organizations of the CNS in the geometric orb-web spider Araneus ventricosus. Similarly to other wandering spiders, the CNS of A. ventricosus is also consisted of a dorsal supraesophageal ganglion and a ventral subesophageal mass. The supraesophageal ganglia are fused together and made up of a large sized nerve cell clusters, whereas the subesophageal ganglia are made up of the foremost part of the ventral nerve cord. It has been revealed that the only nerve arising from the supraesophageal mass was the optic nerve which connected with four pairs of eyes, whereas a pair of pedipalpal and four pairs of appendage nerves including abdominal nerve pairs were arisen from the subesophageal nerve mass. Fibrous masses are highly organized into longitudinal and transverse tracts, and are only consisted of processes of neurons and the terminal ramnifications of peripheral sensory neurons. In addition, central fibrous mass of both the brain and the subesophageal mass are totally devoid of nerve cell bodies.

• Applied Microscopy
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• v.24 no.2
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• pp.1-11
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• 1994

The book lung in the wolf spider, Pardosa astrigera was consisted of a series of flattened triangular-shaped air sacs, stacked with about 70 sheets, and was located in the ventrolateral region of opisthosoma. Each hemolymph spaces (average $8{\mu}m$ in thickness) surrounded by the air sacs (average $6{\mu}m$ in thickness). The air sacs was supported by cylindrical cuticular spikes of microfibril bundles. Epithelial cell processes surrounded the hemolymph spaces. The nuclei of the epithelial cells were concentrated near the atrium. In the middle portion of air sac, the epithelial cells formed pillars across the hemolymph spaces and spot desmosome and zonula adherens were seen between the plasma membranes. In the hemolymph space of this spider, granular hemocytes (average diameter $8{\mu}m$) were the most dominant type of hemocytes. In the medial sinus, the hemolymph flow between the air sacs of a paired book lungs and then flow out of the lung vein. The air comes in the atrium through the ventral lung slit and makes a tidal wave in and out of the air sacs.

• Animal cells and systems
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• v.7 no.1
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• pp.35-41
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• 2003

The principal fibers used in constructing the cocoon in the garden spider, Argiope aurantia, are large-diameter fibers developed from tubuliform glands and small-diameter fibers presumed to be spun by the aciniform silk glands. Scanning electron micrographs of the large-diameter fibers on both surfaces of the cocoon clearly reveal their fine structural differences. While the silk fibers on the inner surface have smooth and homogeneous appearances, each fiber on the outer surface represents a multicomponent internal structure. Examination of each fibers using transmission electron microscope also provides additional evidence that the multicomponent fibers contain numerous electron lucent fibrils embedded in an amorphous electron dense matrix. It has been also revealed that two types of secretory granules presumed to be the precursors of tubuliform fibers are closely related to the production of distinct coloration in luminal contents - brownish and yellowish components. Moreover, these electron-dense granules, possibly precursor of fibrillar component, and electron-lucent granules, possibly precursor of matrix component, are densely packed and remain close to each other without fusion. It is critical evidence that the individual tubuliform fiber is not only heterogeneous and multicomponent but also takes place in a variety at manners throughout the length of the gland.

• Entomological Research
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• v.48 no.5
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• pp.429-438
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• 2018

Fine structural characteristics of the cardiac muscle and its sarcomere organization in the black widow spider, Latrodectus mactans were examined using transmission electron microscopy. The arrangement of cardiac muscle fibers was quite similar to that of skeletal muscle fibers, but they branched off at the ends and formed multiple connections with adjacent cells. Each cell contained multiple myofibrils and an extensive dyadic sarcotubular system consisting of sarcoplasmic reticulum and T-tubules. Thin and thick myofilaments were highly organized in regular repetitive arrays and formed contractile sarcomeres. Each repeating band unit of the sarcomere had three apparent striations, but the H-zone and M-lines were not prominent. Myofilaments were arranged into distinct sarcomeres defined by adjacent Z-lines with relatively short lengths of $2.0{\mu}m$ to $3.3{\mu}m$. Cross sections of the A-band showed hexagon-like arrangement of thick filaments, but the orbit of thin filaments around each thick filament was different from that seen in other vertebrates. Although each thick filament was surrounded by 12 thin filaments, the filament ratio of thin and thick myofilaments varied from 3:1 to 5:1 because thin filaments were shared by adjacent thick filaments.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.257-262
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• 2003

Spider mites and their predacious mites were surveyed in an apple orchard where pesticides have not been applied for a long time, to understand the undisrupted predacious mite complex and their role in the controling spider mites. Spider mites occurring in the orchard were different to those in conventional orchards. A few Tetranychus urticae and Panonychus ulmi were observed, while T. kanzawai was abundant during growing season. Four species of phytoseiids, Amblyseius eharai, A. kokufuensis, A. womersleyi and Typhlodromus vulgaris, and one stigmaeid species of Agistemus terminalis were observed from leaf samples in the orchard. Among them, T. vulgaris occurred from early cool season with low T. kanzawai densities through to mid-and late-season. A. womersleyi was observed only during mid-season when T. kanzawai densities were high with hot weather. Amblyseius eharai and A. kokufuensis occured only in early season, but A. terminalis density increased from mid-season and lasted to late-season. The predacious mite complex regulated the density of T. kanzawai approximately under 8 mites per leaf. Tentatively concluding, T. vulgaris is an adaptable predator at lower prey density under cool weather condition, and A. womersleyi is effective predator at higher prey density under hot weather condition. Further, the biological control strategies of spider mites in Korean orchards were discussed based on the predacious mite complex.

• Journal of Environmental Science International
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• v.17 no.3
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• pp.287-296
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• 2008

A comprehensive quality survey for heavy metals, organophosphorous and organochlorine residual pesticides, and coplanar PCBs in samples such as water, sediments and soils as well as spiders has been implemented. The samples were undertaken at nine stream sites and their vicinity in August 2006, representing different surrounding environments. The levels of PCBs were expressed as concentrations and WHO-TEFs. Among 12 coplanar PCBs as target compounds in this study, 2,3', 4,4', 5-PentaCB (IUPAC # 118) was the congener with the highest concentration. The total concentrations and TEF values of coplanar PCBs in Siheung stream sediment (heavy industrial complex site located in Ansan city) were 3915.50 pg/g and 0.8366 pg-TEQ/g on a dry weight basis, respectively. Such levels were around 40 times higher compared to sediment from Gapyung stream (green site located in the upper of Myunggi mountain). It is probably due to the direct input of PCBs trom PCBs treatment materials. Organophosphorous (EPN, dementon-s-methyl, diazinon, parathion, and phenthoate) and organochlorine (alpha-BHC, aldrin, 4,4'-DDT, 4,4'-DDE, endosulfan alpha and etc.) pesticides were not detected above 5 ppb of detection limits. The concentrations of Cu and Cd in water and sediment samples from Siheung stream were 44.11 and $0.17ug/m\ell$ and $713.42{\mu}g/g$ and $3.73{\mu}g/g$, respectively, which contained $20\sim40$ times higher concentrations than those from Gapyung stream. In addition to the water and sediment samples, the levels of heavy metals in spider from designated sampling sites were also determined. Heavy metals in spider collected near Siheung stream was appeared to be equivalent and/or a little higher levels with respect to other spiders. Furthermore, the ratio of relative heavy metals (Cu, Cd, and Pb) in spider from each stream site showed a correlation as similar as that of heavy metals in soil samples.

• Korean Journal of Microbiology
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• v.37 no.1
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• pp.1-8
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• 2001

Spiders are carnivores that prey upon insects and other small arthropods through digestion of food outside the body. Although spider poison may contain proteolytic enzymes, these are thought to play an insignificant role in actual digestion. The source of active proteolytic enzymes can be either the digestive tract cells of spider, or natural microbial flora in the digestive tract of spider. In this study, digestive tracts from the spider, Nephila clavata, were screened for bacteria that have protease or lipase activity. A total of $10^3-10^5$ CFU was recovered from a spider and more than 90% of them showed protease and lipase activity respectively. Of the microbial isolates, 63.3% showed protease or lipase activity, and 50% of these showed both protease and lipase activity. Some of the isolates were characterized using a battery of chemical, phenotypic and genotypic methods. Eleven Gram negative bacteriaa (Acinetobacter calcoaceticus, A. haemolyticus, Alcaligenes faecalis, Cedecea davisae, C. neteri, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas fluorescens, Serratia marcescens, Stenotrophomonas maltophilia, Suttonella indologenes) and 11 Gram positive bacteria (Bacillus cereus, B. coagulans, B. pasteurii, B. thuringiensis, Cellulomonas flavigena, Corynebacterium martruchotii, Enterococcus durans, E. faecalis, Micrococcus luteus, Staphylococcus hominis, S. sciuri) were identified.

• Applied Microscopy
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• v.38 no.2
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• pp.89-96
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• 2008

Dolomedes spiders of the family Pisauridae are one of free wandering spiders with semi-aquatic habitation. They do not build web for prey-hunting but build a nursery web for spiderlings. This paper describes the fine structure of the silkspinning spigots of the fishing spider Dolomedes sulfureus revealed by the field emission scanning electron microscope (FESEM). The fishing spider Dolomedes sulfureus possesses only three types of silk glands which connected through the typical spinning tubes on the spinnerets. The silk spigots of this spider were identified as three groups: ampullates, pyriforms and aciniforms. Two pairs of major ampullate glands send secretory ductules to the anterior spinnerets, and another two pairs (or $1{\sim}2$ pairs in males) of minor ampullate glands supply the middle spinnerets. In addition, the pyriform glands feed silk into the anterior spinnerets ($62{\sim}68$ pairs in females and $45{\sim}50$ pairs in males), and the aciniforms send ductules to the middle ($33{\sim}40$ pairs in females and $18{\sim}25$ pairs in males) and the posterior spinnerets ($42{\sim}50$ pairs in females and $24{\sim}28$ pairs in males). Among these, the ampullate one is the most predominate gland in both sexes.