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61.
Driscoll CA Menotti-Raymond M Roca AL Hupe K Johnson WE Geffen E Harley EH Delibes M Pontier D Kitchener AC Yamaguchi N O'brien SJ Macdonald DW 《Science (New York, N.Y.)》2007,317(5837):519-523
The world's domestic cats carry patterns of sequence variation in their genome that reflect a history of domestication and breed development. A genetic assessment of 979 domestic cats and their wild progenitors-Felis silvestris silvestris (European wildcat), F. s. lybica (Near Eastern wildcat), F. s. ornata (central Asian wildcat), F. s. cafra (southern African wildcat), and F. s. bieti (Chinese desert cat)-indicated that each wild group represents a distinctive subspecies of Felis silvestris. Further analysis revealed that cats were domesticated in the Near East, probably coincident with agricultural village development in the Fertile Crescent. Domestic cats derive from at least five founders from across this region, whose descendants were transported across the world by human assistance. 相似文献
62.
Methane uptake and nitrous oxide emission in Japanese forest soils and their relationship to soil and vegetation types 总被引:1,自引:1,他引:1
Tomoaki MORISHITA Tadashi SAKATA Masamichi TAKAHASHI Shigehiro ISHIZUKA Takeo MIZOGUCHI Yoshiyuki INAGAKI Kazuhiko TERAZAWA Satoshi SAWATA Masanori IGARASHI Hiroshi YASUDA Yasuhiro KOYAMA Yoshihito SUZUKI Nobuyuki TOYOTA Masamichi MURO Masaru KINJO Hirokazu YAMAMOTO Daitaro ASHIYA Yoichi KANAZAWA Tetsu HASHIMOTO Hidetaka UMATA 《Soil Science and Plant Nutrition》2007,53(5):678-691
63.
Tomato plants (Lycopersicon esculentum) synthesize the glycoalkaloids dehydrotomatine and alpha-tomatine, possibly as a defense against bacteria, fungi, viruses, and insects. We used a high-performance liquid chromatography method with UV detection at 208 nm for the analysis of these compounds in various tissues. An Inertsil ODS-2 column with a mobile phase of acetonitrile/20 mM KH2PO4 (24/76, v/v) afforded good separation of the two glycoalkaloids in mini-tomato extracts, fruit harvested at different stages of maturity, and calyxes, flowers, leaves, roots, and stems. The two peaks appeared at approximately 17 and approximately 21 min. Recoveries from tomato fruit extracts spiked with dehydrotomatine and alpha-tomatine were 87.7 +/- 6.8 and 89.8 +/- 3.4% (n = 5), respectively. The detection limit is estimated to be 0.39 microg for dehydrotomatine and 0.94 microg for alpha-tomatine. The dehydrotomatine and alpha-tomatine content of tomatoes varied from 42 to 1498 and 521 to 16 285 microg/g of fresh weight, respectively. The ratio of alpha-tomatine to dehydrotomatine ranged from 10.9 to 12.5 in tomatoes and from 2.3 to 7.8 in the other plant tissues. These results suggest that the biosynthesis of the glycoalkaloids is under separate genetic control in each plant part. Degradation of both glycoalkaloids occurred at approximately the same rate during maturation of the tomatoes on the vine. An Inertsil NH2 column, with acetonitrile/1 mM KH2PO4 (96/4, v/v) as the eluent, enabled the fractionation of commercial tomatidine into tomatidenol and tomatidine, the aglycons of dehydrotomatine and alpha-tomatine, respectively. The information should be useful for evaluating tomatoes and vegetative tissues for dehydrotomatine/alpha-tomatine content during fruit development and their respective roles in host-plant resistance and the diet. 相似文献
64.
Mekuriaw Shigdaf Tsunekawa Atsushi Ichinohe Toshiyoshi Tegegne Firew Haregeweyn Nigussie Nobuyuki Kobayashi Tassew Asaminew Mekuriaw Yeshambel Walie Misganaw Tsubo Mitsuru Okuro Toshiya 《Tropical animal health and production》2020,52(3):1287-1298
Tropical Animal Health and Production - Browse species are important sources of forage for livestock in Ethiopia, especially during the dry season, when the quality and quantity of green herbage is... 相似文献
65.
Ikutaro Tsuyama Katsuhiro Nakao Tetsuya Matsui Motoki Higa Masahiro Horikawa Yuji Kominami Nobuyuki Tanaka 《Annals of Forest Science》2011,68(4):689-699
Introduction
The aims of this study were to identify the climatic conditions controlling the distribution of Sasamorpha borealis and to assess the impact of climate change on the species in Japan. 相似文献66.
Citrus psorosis virus (CPsV) was detected from citrus trees for the first time in Japan. The diagnosis was confirmed by molecular, serological,
and biological indexing. RT-PCR detected CPsV from two citrus trees among ca. 200 tested. Both trees were variety Shiranui
of [Citrus unshiu Marc. × C. sinensis (L.) Osb.] × C. reticulata Blanco, and neither had the bark scaling symptom typical of CPsV. The CPsV isolate could be genetically related to those
from Spain, Italy, Florida, and California. 相似文献
67.
Hayashi N Ujihara T Tanaka E Kishi Y Ogawa H Matsuo H 《Journal of agricultural and food chemistry》2011,59(18):10317-10321
To obtain basic knowledge about the relationship between the application of organic fertilizers and the δ15N values of leaves of organically grown tea plants, annual variations in the δ15N values of the tea leaves were investigated. Although variations did not immediately arise after the application of organic fertilizers, differences in the δ15N values between organic and conventional cultivations appeared basically after three years from the beginning of the organic cultivation except when an organic fertilizer with a low δ15N value was applied, and the variation depended on the δ15N values of the fertilizers. In addition, the effectiveness of the δ15N values as a practical indicator of organic teas was examined. The tea leaves collected from organic farms did not always have higher δ15N values than the commercially available nonorganic teas. This result demonstrates that it is not easy to discriminate organic teas from nonorganic teas simply by their δ15N values. 相似文献
68.
69.
Emi Morita Kyoko Aoyama Takashi Tamura Rieko Okada Sayo Kawai Yoshinori Ito Mariko Naito Kenji Wakai Nobuyuki Hamajima 《Journal of Forest Research》2013,18(6):454-461
The frequency of forest walking among the general population is a major topic of study in forest science. The objectives of this study were threefold: to assess the frequency of forest walking among Japanese residents of Nagoya, a large city; to evaluate differences among frequency of forest walking by participants from a large city, an urban area (Shizuoka; 4,666 participants), and a rural area (Yakumo Town, Hokkaido; 397 participants) in previous studies; and to examine factors related to frequency of forest walking. The survey, by self-administered questionnaire, in the major city of Nagoya was conducted between June 2008 and May 2010. In all, 5,158 participants (M/F, 1,466/3,692; mean age ± SD [range], 52.5 ± 10.3 [35–69] years) were included in the analysis. The proportions of frequency of forest walking ≥ once/month and ≥ once/year were 10.9 % (M/F, 15.1/9.3 %) and 46.1 % (51.0/44.1 %), respectively. In multiple logistic regression analysis, significant differences were noted among study sites for the adjusted odds ratio for frequency of forest walking. Overall, the order of highest to lowest frequency of forest walking was Shizuoka > Nagoya > Yakumo. Factors related to frequency of forest walking were common among the three study sites. Higher frequency of forest walking was associated with male sex and older age; the most relevant factor related to frequency of forest walking was its enjoyment level. Further studies will be required to clarify why these factors are related to frequency of forest walking. 相似文献
70.