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71.
SUH Eun Young Kwang Hee SON Dong Ha SHIN Ki Duk KIM Cheol JANG Yong Man YU Ho-Yong PARK 《Entomological Research》2002,32(3):133-139
ABSTRACT A new insect pathogenic fungi, Paecilomyces licacinus HY-4 that was isolated from soil sample, showed biological activity to Chestnut Brown Chafer, pest of golf course. The culture condition for the fungi P. lilacinus HY-4 was optimized through statistical approach for the mass production. According th the bioassay on the pest, the insecticidal activity reached up to 30%, and positive factor for the production of the fungi was zeolite with 97.5% of significance. 相似文献
72.
Can labels suggestively influence sensory perceptions and taste? Using a “ Phantom Ingredient” taste test, we show that the presence or absence of a labeled ingredient (soy) and the presence or absence of a health claim negatively bias taste perceptions toward a food erroneously thought to contain soy. We found a label highlighting soy content made health claims believable but negatively influenced perceptions of taste for certain segments of consumers. Our results and discussion provide better direction for researchers who work with ingredient labeling as well as for those who work with soybean products. 相似文献
73.
Cultivated Agave mapisaga and A. salmiana can have an extremelyhigh above-ground dry-weight productivity of 40 Mg ha1yr1. To help understand the below-ground capabilitiesthat support the high above-ground productivity of these Crassulaceanacid metabolism plants, roots were studied in the laboratoryand in plantations near Mexico City. For approximately 15-year-oldplants, the lateral spread of roots from the plant base averaged1.3 m and the maximal root depth was 0.8 m, both considerablygreater than for desert succulents of the same age. Root andshoot growth occurred all year, although the increase in shootgrowth at the beginning of the wet season preceded the increasein growth of main roots. New lateral roots branching from themain roots were more common at the beginning of the wet season,which favoured water uptake with a minimal biomass investment,whereas growth of new main roots occurred later in the growingseason. The root: shoot dry weight ratio was extremely low,less than 0.07 for 6-year-old plants of both species, and decreasedwith plant age. The elongation rates of main roots and lateralroots were 10 to 17 mm d1, higher than for various desertsucculents but similar to elongation rates for roots of highlyproductive C3 and C4 agronomic species. The respiration rateof attached main roots was 32 µmol CO2 evolved kg1dry weight s1 at 4 weeks of age, that of lateral rootswas about 70% higher, and both rates decreased with root age.Such respiration rates are 4- to 5-fold higher than for Agavedeserti, but similar to rates for C3 and C4 agronomic species.The root hydraulic conductivity had a maximal value of 3 x 107ms1 MPa1 at 4 weeks of age, similar to A. deserti.The radial hydraulic conductivity from the root surface to thexylem decreased and the axial conductivity along the xylem increasedwith root age, again similar to A. deserti. Thus, although rootsof A. mapisaga and A. salmiana had hydraulic properties perunit length similar to those of a desert agave, their highergrowth rates, their higher respiration rates, and the greatersoil volume explored by their roots than for various desertsucculents apparently helped support their high above-groundbiomass productivity Key words: Crassulacean acid metabolism, productivity, root elongation rate, root system, water uptake 相似文献
74.
Eun-Kee PARK 《Entomological Science》2007,10(2):135-140
The collembolan Proisotoma minuta (Tullberg) was successfully maintained in a laboratory culture that could be used to produce large numbers of P. minuta of standard size and physiological condition. The general life history of P. minuta was studied using a substrate comprising a mixture of plaster of Paris and charcoal with baker's yeast as food. The mean time taken for eggs to hatch following oviposition was 10.6 ± 1.3 days at 17.5°C and 6 ± 0.5 days at 23°C. Conditions in the culture were very important for the production of large insect populations. Growth of the cultures was limited by the increasing population size and was probably affected by contamination of the habitat by the deposition of excretory materials. Proisotoma minuta from a population that had ceased egg production started oviposition after individuals were transferred to a fresh plaster of Paris and charcoal habitat. 相似文献
75.
ABSTRACT Larval features of the carabid beetle, Damaster (Coptolabrus) jankowskii jankowskii (Oberthür) were investigated for the first time. For accomplishing the purpose, the adult beetles were collected by pitfall traps in the deciduous forest of Mt. Palgongsan, southern Korea. They have been reared under the laboratory condition of 16L: 8D at 20°C. The first instar larvae were obtained by isolating eggs after oviposition and were kept at the same condition. In the present study, external morphology of the first instar larva of this subspecies are described and its important character states and comparisons with the kin species are also discussed. 相似文献
76.
77.
Kyu‐Tek PARK 《Entomological Science》2011,14(1):82-86
Two new species of the genus Telephata Meyrick which has been known to be monotypic, T. melanista, sp. nov. and T. ferruginula, sp. nov., are described from Papua New Guinea. A known species from the island, Lecithocera nitens Daikonoff, is transferred to this genus; Telephata nitens (Diakonoff), comb. nov. Keys to the species of Telephata, based on external and genital characters are given, along with illustrations of adults, wing venations, and male genitalia. 相似文献
78.
Adipose tissue-derived stem cells (ADSCs) are one population of adult stem cells that can self renew and differentiate into
multiple lineages. Because of advantages in method and quantity of acquisition, ADSCs are gaining attention as an alternative
source of bone marrow mesenchymal stem cells. In this study, we performed microRNA profiling of undifferentiated and of neurally-differentiated
ADSCs to identify the responsible microRNAs in neurogenesis using this type of stem cell. MicroRNAs from four different donors
were analysed by microarray. Compared to the undifferentiation control, we identified 39–101 microRNAs with more than two-fold
higher expression and 3–9 microRNAs with two-fold lower expression. The identified microRNAs were further analysed in terms
of gene ontology (GO) in relation with neurogenesis, based on their target mRNAs predicted by computational analysis. This
study revealed the specific microRNAs involved in neurogenesis via microRNA microarray, and may provide the basic information
for genetic induction of adult stem cell differentiation using microRNAs. 相似文献
79.
Last instar larvae of Pyrrhalta annulicornis, P. fuscipennis, P. humeralis, P. lineola and P. maculicollis are described and illustrated for the first time in Korea. Their taxonomic remarks, tubercle patterns and a key are also given. 相似文献
80.