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121.
Youngho CHO Youngjin KIM Yong-Gu HAN Young Kook KANG Minjoo CHOI Heonmyoung LIM Youngjun PARK Sang-Ho NAM 《Entomological Research》2010,40(5):270-276
Six species of insect endoparasitoids were identified from Elcysma westwoodii, which is the most damaging lepidopteran pest of Prunus yedoensis. From Hymenoptera, two species were identified: a species in Braconidae and Charops striatus in Ichneumonidae. From Diptera, there were four species in Tachinidae: Compsilura concinnata, Exorista sp., Pales sp. and Tachinidae spp. The parasitic ratio was 4.86% (45 of 926 larvae). The hymenopterans were parasitic on 31 individuals of E. westwoodii (68.9%) and the dipterans were parasitic on 14 individuals (31.1%). It was found that parasitoids from the larvae of E. westwoodii were all either endoparasitoids or larval parasitoids. However, Exorista sp. of Tachinidae was found to be either a larval parasitoid or larval-pupal parasitoid. Additionally, all the identified parasitoids were solitary parasitoids, as only one parasite occurred in a larva of E. westwoodii. Because the larva of E. westwoodii eats and molts after it is parasitized, all the parasitoids were identified as koinobionts. There were no big differences in morphological characteristics and life histories between C. striatus and C. concinnata. However, for Exorista sp. and Pales sp., males took 3–5 days longer to emerge from their pupae and had remarkably longer body lengths than females. 相似文献
122.
Internal Leaf Area and Cellular CO2 Resistance: Photosynthetic Implications of Variations with Growth Conditions and Plant Species 总被引:5,自引:0,他引:5
PARK S. NOBEL 《Physiologia plantarum》1977,40(2):137-144
The influences of illumination, temperature, and soil water potential during development on leaf thickness, mesophyll cell wall area per unit leaf area (Ames/A), and the cellular CO2, resistance expressed on a mesophyll cell wall area basis (rCO2cell,) were examined for Plectranthus parviflorus Henckel. Although the ranges of all three growth conditions caused at least 9-fold variations in the leaf biomass produced in 4 weeks, only the illumination had a major effect on internal leaf morphology, e.g. the thickness went from 279 to 831 μm and Ames/A from 10.5 to 34.8 as the photosynthetically active radiation was raised from 3 to 53 nEinsteins cm?2 s?1, while rCO2cell remained close to 154 s cm?1. Variations in the growth temperature, soil water potential, and the nutritional status of the plant, affected photosynthesis mainly by changes in rCO2cell. To compare the influence of internal leaf area on photosynthesis for other plants, especially those with low Ames/A values, the maximum rates of CO2 uptake at light saturation and photosynthetically optimal temperatures were also determined for a moss, Mnium ciliare (C. Muell.) Schimp., and two ferns, Adiantum decorum Moore and Alsophila australe R. Br. As Ames/A went from 2.00 for the moss to 3.8, 7.5, 11.7, and 20.8 for the fens, the illumination at light saturation and the maximum rate of photosynthesis both progressively increased. The cellular CO2 resistance, which theoretically might have a lower limit of 20 s cm?1, ranged from 85 to 190 s cm?1. 相似文献
123.
The genus Thubana Walker (Lepidoptera: Lecithoceridae: Torodorinae) in Indonesia is reviewed, with three known species from Java and four additional new species: Th. raphidodea sp. nov. from Sulawesi, Indonesia and Malaysia; and Th. erycinae sp. nov., Th. apiculalis sp. nov. and Th. sellarius sp. nov. from Sumatra, Indonesia. The previously known species from Java, Th. costimaculella (Snellen), is redescribed for the wing venation and genitalia of both sexes; however, the syntype of Th. heylaertsi (Snellen) is observed only by its photograph. No specimens of Th. heylaertsi and Th. xylogramma Meyrick were found during this study. Photos of all known species, except Th. xylogramma Meyrick, and a key to species are provided. A catalog for the genus with all 46 known species in the world is given. 相似文献
124.
JONG SOO PARK MARTIN KOLISKO AARON A. HEISS ALASTAIR G.B. SIMPSON 《The Journal of eukaryotic microbiology》2009,56(4):373-384
ABSTRACT. We describe Hicanonectes teleskopos n. g., n. sp., a heterotrophic flagellate isolated from low-oxygen marine sediment. Hicanonectes teleskopos has a ventral groove and two unequal flagella, and rapidly rotates during swimming. At the ultrastructural level H. teleskopos is a "typical excavate": it displays flagellar vanes, a split right microtubular root, "I,""B," and "C" fibres, a singlet microtubular root, and a possible composite fibre. Small subunit rRNA (SSU rRNA) gene phylogenies and an "arched" B fibre demonstrate that H. teleskopos belongs to Fornicata (i.e. diplomonads, retortamonads, and relatives). It forms a clade with the deep-branching fornicate Carpediemonas , with moderate-to-strong bootstrap support, although their SSU rRNA gene sequences are quite dissimilar. Hicanonectes differs from Carpediemonas in cell shape, swimming behaviour, number of basal bodies (i.e. 4 vs. 3), number of flagellar vanes (i.e. 2 vs. 3), anterior root organization, and by having a cytopharynx. Like Carpediemonas and Dysnectes, Hicanonectes has conspicuous mitochondrion-like organelles that lack cristae and superficially resemble the hydrogenosomes of parabasalids, rather than the mitosomes of their closer relatives the diplomonads (e.g. Giardia ). 相似文献
125.
126.
TAE-YOON PARK DUCK K. CHOI 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2010,43(1):73-87
Park, T.-Y. & Choi, D.K. 2010: Two middle Cambrian diceratocephalid trilobites, Cyclolorenzella convexa and Diceratocephalus cornutus , from Korea: development and functional morphology. Lethaia , Vol. 43, pp. 73–87.
Silicified sclerites of the latest middle Cambrian trilobites, Cyclolorenzella convexa and Diceratocephalus cornutus , have been recovered from the Sesong Formation, Korea. Their morphological similarity and stratigraphic occurrences suggest that D. cornutus is a descendant of C. convexa . The ontogenies of both trilobites demonstrate that a pair of long frontal horns in the cephalon of D. cornutus is an evolutionarily novel structure. It is inferred that redeployment of some pre-existing regulatory gene played a significant role in constructing the frontal horns of D. cornutus . The frontal horns may have been a defensive structure to deter predators. The facial suture of D. cornutus , which extends onto the frontal horns and splits them into the dorsal and ventral halves, was a solution to enable easier forward egression during ecdysis. □ Functional morphology, Korea, Middle Cambrian, ontogeny, trilobites . 相似文献
Silicified sclerites of the latest middle Cambrian trilobites, Cyclolorenzella convexa and Diceratocephalus cornutus , have been recovered from the Sesong Formation, Korea. Their morphological similarity and stratigraphic occurrences suggest that D. cornutus is a descendant of C. convexa . The ontogenies of both trilobites demonstrate that a pair of long frontal horns in the cephalon of D. cornutus is an evolutionarily novel structure. It is inferred that redeployment of some pre-existing regulatory gene played a significant role in constructing the frontal horns of D. cornutus . The frontal horns may have been a defensive structure to deter predators. The facial suture of D. cornutus , which extends onto the frontal horns and splits them into the dorsal and ventral halves, was a solution to enable easier forward egression during ecdysis. □ Functional morphology, Korea, Middle Cambrian, ontogeny, trilobites . 相似文献
127.
JUNG YOUN PARK SANG‐JUN LEE HAE WON LEE YONG GUG LEE SO JUNG JUNG YONG JOO KANG 《Molecular ecology resources》2006,6(3):674-676
We developed 12 polymorphic microsatellite markers from Arctoscopus japonicus by screening an enriched genomic library using polymerase chain reaction (PCR) techniques. The average of alleles size was 16.2, and the average observed and expected heterozygosities were 0.59 and 0.78, respectively. The observed genotypic frequencies in five loci were significantly deviated from Hardy–Weinberg expectations. The high variability revealed in this study suggested that these microsatellite loci should provide useful markers for population genetics of A. japonicus. 相似文献
128.
小前胡中香豆素类成分研究 总被引:4,自引:0,他引:4
本文对韩国植物新种小前胡(Angelica czernaeviaKita forma dentate Yook)的根部进行了化学成分研究,从中得到了7个香豆素类化合物,利用波谱方法分别鉴定为异欧前胡素(1),川白芷内酯(2),紫花前胡素(3),7-羟基香豆素(4),紫花前胡醇(5),紫花前胡苷元(6)和紫花前胡苷(7);同时采用高效液相色谱法对该植物的根、茎、叶和果实进行了主成分川白芷内酯(2)和紫花前胡素(3)定量分析。 相似文献
129.
We tested the hypothesis that increased telencephalon size has evolved in threespine stickleback fish (Gasterosteus aculeatus) from structurally complex habitats using field‐caught samples from one sea‐run (ancestral) and 18 ecologically diverse freshwater (descendant) populations. Freshwater habitats ranged from shallow, structurally complex lakes with benthic‐foraging stickleback (benthics), to deeper, structurally simple lakes in which stickleback depend more heavily on plankton for prey (generalists). Contrary to our expectations, benthics had smaller telencephala than generalists, but the shape of the telencephalon of the sea‐run and benthic populations were more convex laterally. Convex telencephalon shape may indicate enlargement of the dorsolateral region, which is homologous with the tetrapod hippocampus. Telencephalon morphology is also sexually dimorphic, with larger, less convex telencephala in males. Freshwater stickleback from structurally complex habitats have retained the ancestral telencephalon morphology, but populations that feed more in open habitats on plankton have evolved larger, laterally concave telencephala. 相似文献
130.
The species Tanysphyrus (Tanysphyroides) major Roelofs is recorded for the first time from Korea. This paper reports the diagnostic characters, and some remarks on its systematics and notes on its biology are also provided. 相似文献