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81.
印尼岛的柚木心材在年轮周围显示了不规则的黑色条纹变化。本研究调查柚木黑色条纹心材的颜色和化学特性。利用色坐标(CIELAB)测定颜色特性(pH值、无机物含量、抽出物含量和特性)。结果表明:黑色条纹的颜色较对照少12-15个亮度单位。因此,黑色条纹的颜色与对照比较,有较多的红色,较少的黄色、色彩和色度。黑色条纹心材部分的pH值灰度含量和钙含量都比对照的高。黑色条纹的心材抽出物含量较对照的高。推测当生物活性物质(杀虫剂)明显增加时,心材显示发黑的过程可能是一种防御机制。 相似文献
82.
Narihito Ogawa Ryoya Imaizumi Tatsuya Hirano Jun Suzuki 《Journal of Pesticide Science》2021,46(3):278
We investigated the synthesis and herbicidal activity of 23 toxoflavin analogs, 1a–w, in which aromatic rings (R) were introduced into the C-3 position. In paddy field conditions, 1k (R=2-CF3–C6H4) and 1w (R=2-thienyl) showed excellent herbicidal activity. Under upland field conditions, we found that toxoflavin analogs 1a (R=C6H5), 1n (R=2-CH3O–C6H4), and 1p (R=4-CH3O–C6H4) exhibited wide herbicidal spectrum against Echinochloa crus-galli (L) var. crus-galli (ECHCG), Chenopodium album, and Amaranthus viridis (AMAVI). The analog with the 2-fluoro group on benzene ring 1b also showed high herbicidal activity against both ECHCG and AMAVI. 相似文献
83.
The chemical compositions of the dichloromethane extracts of inner and outer barks from six Pinus species(P.elliotii,P.oocarpa,P.caribeae,P.merkusii,P.montezumae,and P.insularis) grown in Indonesia were investigated by GC and GC–MS.Generally,the amounts of extractive contents were higher in the inner bark than in the outer bark except for P.merksuii.Fatty acids,monoterpenes,sesquiterpenes,resin acids,triterpenoids,and steroids were detected and quantified.Inner and outer barks differed not only in content of these compounds but also in their composition.Fatty acids and alcohols were the major classes of lipophilic compounds in the outer bark of P.caribeae, P.insularis,and P.montezumae.Steroids and triterpenoids were the dominant compounds identified in the inner bark of P.elliotii,P.insularis,and P.merkusii.Resin acids were the most abundant group in the inner bark of P.oocarpa whereas monoterpenes and sesquiterpenes were recorded in minor quantities in both bark layers of all species. 相似文献
84.
Tatsuya Nagata Luisa S. Dutra Priscila A. Oliveira Antonio C. de Ávila Alice K. Inoue-Nagata 《Journal of General Plant Pathology》2010,76(4):268-272
A novel viral disease of melon, caused by Melon yellowing-associated virus (MYaV), has become one of the most serious problems
for melon production in Brazil. Despite its importance, little is known about the genome sequence of the virus. In this study,
the triple gene block genomic region including the 3′-end region of an isolate of MYaV was elucidated (ca. 3.1 kb). Sweet
potato chlorotic fleck virus, a newly suggested carlavirus species, was the most closely related virus with 62% nucleotide
identity. The presence of two heptanucleotide-motifs for subgenomic RNA synthesis was confirmed in this sequence. 相似文献
85.
Masashi Yamamoto Asad Asadi Abkenar Ryoji Matsumoto Tatsuya Kubo Shigeto Tominaga 《Genetic Resources and Crop Evolution》2008,55(8):1167-1173
Fluorochrome staining with chromomycin A3 (CMA) was used to characterize and compare the CMA banding patterns of chromosomes of 17 species from 13 genera of Aurantioideae,
which is one of the seven subfamilies of Rutaceae. All species used in this study had 2n = 18 chromosomes. These chromosomes
were classified into five types based on the number and position of CMA-positive bands; B: one telomeric and one proximal
band, C: two telomeric bands, D: one telomeric band, E: without bands and Dst: type D with a satellite chromosome. Each species
possessed two or four types of chromosomes and unique CMA banding patterns. The CMA banding patterns were 6D + 12E in Clausena anisata (Willd.) Hook. f.,1C + 3D + 14E in Murraya koenigii (L.) Spreng., 1C + 11D + 6E in Murraya paniculata (L.) Jack, 1B + 1C + 10D + 6E in Merrillia caloxylon (Ridl.) Swing., 1C + 9D + 7E + 1Dst in Paramignya lobata Burkill, 2C + 5D + 11E in Severinia buxifolia (Poir.) Tenore, 5D + 13E in Hesperethusa crenulata (Roxb.) Roem., 16D + 2E in Citropsis gabunensis (Engl.) Swing. et M. Kell, 14D + 4E in Citropsis schweinfurthii (Engl.) Swing. et M. Kell, 8D + 10E in Atalantia monophylla DC., 1C + 3D + 14E in Atalantia ceylanica (Arn.) Oliv., 2D + 16E in Atalantia roxburghiana Hook. f., 18E in Swinglea glutinosa (Blanco) Merr., 2D + 16E in Aegle marmelos (L.) Corr., 4D + 14E in Afraegle paniculata (Schum.) Engl., 2B + 2D + 13E + 2Dst in Feronia limonia (L.) Swing. and 3B + 9D + 6E in Feroniella oblata Swing. The advanced genera in each tribe and subtribe such as Merrillia and Feroniella showed heterochromatin (CMA-positive bands) rich chromosome configuration in general. Swinglea glutinosa without heterochromatin rich chromosome, which is considered to be the most primitive chromosome configuration, seems to
be the key genus for clarifying the evolution of the tribe Citreae. 相似文献
86.
The identification of homogeneous management zones (MZs) within a field is a basis for site-specific management (SSM). We
assessed the method of defining MZs based on the spatio-temporal homogeneity of six soil properties and above-ground biomass
data from paddy rice, winter wheat and soybean over 3 years on a farm with 124 contiguous small paddy fields. The soil data
were recorded at 372 soil sampling sites on a rectangular grid over the farm. A non-hierarchical cluster analysis was applied
to the soil data and the algorithm grouped the sites into three clusters with similar soil properties. These clusters represent
soil fertility and soil drainage. The three clusters were not randomly distributed across the fields, but formed contiguous
areas associated with landscape position. This was due to the spatial variation of the soil in the study area. We delineated
five MZs based on the spatial structure of the soil heterogeneity of the study area. The validity of the MZs was evaluated
using the biomass data from paddy rice, winter wheat and soybean in each MZ; this depended mainly on soil fertility when conditions
were dry. When the growing season precipitation was greater than the 10-year average, the biomass of winter wheat and soybean
depended on soil drainage. This suggested that the delineation of MZs for site-specific management in fields under a paddy-upland
crop rotation system should be based on several soil properties. The biomass data from the three crops over 3 years was not
effective for delimiting MZs. 相似文献
87.
Mayuko OKI Mitsutaka IKEZAWA Tatsuya NISHI Katsuhiko FUKAI Manabu YAMADA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(1):48
We detected the classical swine fever virus (CSFV) antigen in three boar-pig hybrids (hybrids) and three pigs. All animals were experimentally infected with CSFV strain JPN/27/2019 to optimize diagnostic sampling and risk assessment of virus dissemination. Two hybrids died 17- and 19-days post-inoculation (dpi). The other animals were euthanized at 28 dpi. The detection of CSFV antigen at 28 dpi in epithelial cells of the apocrine sweat and sebaceous glands in the skin, salivary glands, mucosal epithelial cells in the rectum, and epithelial cells in the kidney and urinary bladder, suggests that CSFV persists in these tissues and spreads via sweat, saliva, feces, and urine for at least 4 weeks. These findings reveal that hybrids and pigs represent a high risk of virus dissemination four weeks after infection with CSFV strain JPN/27/2019. Prominent CSFV antigens were also detected in hair follicles of the skin. These results suggest that postmortem sampling of animal skin may be effective for CSF diagnosis and can be used to develop a rapid and easy diagnostic method using hair follicles. 相似文献
88.
Fisheries Science - We investigated the compositions of free amino acids (FAAs), organic acids (OAs), and nucleotides and their related compounds (NAs) in the gonads of edible sea urchins in Japan.... 相似文献
89.
Cen Tao Tatsuya Sugawara Sayaka Maeda Xichang Wang Takashi Hirata 《Fisheries Science》2008,74(5):1166-1172
Antioxidative activities of porphyra-334, a mycosporine-like amino acid extracted from laver were evaluated. Oxidation of
linoleic acid induced by an alkyl-radical 2,2′-azobis (2-amidinopropane) dihydrochloride (AAPH) was successfully suppressed
by porphyra-334 (0–200 μM). The simultaneous application of 0.02 μM α-tocopherol and 50 μM porphyra-334 effectively suppressed
the AAPH induced oxidation level to approximately 40% of a single application of porphyra-334 after 10 min reaction. Porphyra-334
(0–200 μM) efficiently suppressed the lipid peroxidation induced by singlet oxygen although the antioxidative effect observed
was relatively moderate at the initial stage of oxidation. These results suggested that porphyra-334 may function as an antioxidant
which influences the storage stability of laver. 相似文献
90.
Tadahide Kurokawa Takuma Okamoto Koichiro Gen Susumu Uji Koji Murashita Tatsuya Unuma Kazuharu Nomura Hajime Matsubara Shin‐Kwon Kim Hiromi Ohta Hideki Tanaka 《Journal of the World Aquaculture Society》2008,39(6):726-735
The occurrence of morphological deformities under different rearing water temperatures (18, 20, 22, 24, 26, 28, and 30 C) was examined in Japanese eel larvae. The rates of hatching and survival until yolk resorption at 22–26 C were higher than those at other water temperatures. Fertilized eggs never hatched at 18 and 30 C. The rates of occurrence of abnormal larvae reared at the water temperatures 24–28 C were lower than those at 20 or 22 C. Pericardial edema and lower jaw deformities occurred most frequently at lower temperatures (20 and 22 C). In contrast, the incubation temperature did not significantly affect the relative frequency of some neurocranial deformities and of spinal curvature. These results imply that the optimal temperatures for rearing Japanese eel eggs and embryos are 24–26 C from the viewpoints of survival and deformity. 相似文献