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61.
Masanori Mitsuchi 《Soil Science and Plant Nutrition》2013,59(4):141-146
On the high terrace to the north of Akashi City, Sanyo District. th ere is a heavy text ured soil which is charac te rized by the presence of altern ate red and gray bands in lower hor izons (photo.) . This soil is called "Tora-han" Soil as a local name by reason of its morph ological resemblance to “tora” (tiger*). Heavy textured soils which have tiger-like (or zebra-like) mot tlings in lower hor izons are also found in other parts of Japan alm ost excl usively on high ter races , and hav e long attracted th e attent ion of Japanese pedologists. 相似文献
62.
Masanori Miyazaki 《Scientia Horticulturae》1975,3(2):109-128
This study was carried out to investigate the factors concerning the accumulation of nitrate in tomato fruit and to find the preventive measures against heavy tin-dissolving in canned tomato juice caused by nitrate.The factors determining the accumulation of nitrate in the plant were as follows: the levels of nitrate, potassium, and calcium in the soil, the application of plant growth regulators, the tomato cultivar, and the light intensity. For obtaining fruits containing less than 3 ppm of nitrate-nitrogen, low nitrate cultivars should be grown in a sunny place on weak acid soil with split application of slow-acting nitrogen fertilizer, and a high calcium level. By proper treatment with plant growth regulators, nitrate-nitrogen content in the fruit can be decreased still more. It is also important that any particular growing-conditions in every tomato-growing district should be taken in consideration in the cultivation management for preventing the accumulation of nitrate-nitrogen. 相似文献
63.
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65.
Maeda K Kawabata K Mazzali PA Tanaka M Valenti S Nomoto K Hattori T Deng J Pian E Taubenberger S Iye M Matheson T Filippenko AV Aoki K Kosugi G Ohyama Y Sasaki T Takata T 《Science (New York, N.Y.)》2008,319(5867):1220-1223
Core-collapse supernovae (CC-SNe) are the explosions that announce the death of massive stars. Some CC-SNe are linked to long-duration gamma-ray bursts (GRBs) and are highly aspherical. One important question is to what extent asphericity is common to all CC-SNe. Here we present late-time spectra for a number of CC-SNe from stripped-envelope stars and use them to explore any asphericity generated in the inner part of the exploding star, near the site of collapse. A range of oxygen emission-line profiles is observed, including a high incidence of double-peaked profiles, a distinct signature of an aspherical explosion. Our results suggest that all CC-SNe from stripped-envelope stars are aspherical explosions and that SNe accompanied by GRBs exhibit the highest degree of asphericity. 相似文献
66.
Acid deposition has been monitored in the natural vegetation of the western part of Tokyo, especially in the Okutama Mountains and surrounding areas. However, it is difficult to grasp the condition of acid deposition and the possible impacts on the vegetation in the whole area. Therefore, we attempted to make gridded acidic deposition maps and critical load maps. The grid size was 30 seconds latitude and 45 seconds longitude. Monthly wet deposition in the fiscal year of 1997 was calculated by multiplying concentration of wet deposition and precipitation. Concentration of wet deposition was estimated by averaging the data monitored at the nearest three stations with the inverse of distance as the weight. Precipitation was estimated by step-wise multiple regression with geographical factors as explanatory variables. Critical loads were estimated using the steady-state mass balance model with some modifications. As result, it was found that sulfur deposition had exceeded in most of the western part of Tokyo. 相似文献
67.
Production of triploid plants of Japanese pear (Pyrus pyrifolia Nakai) by anther culture 总被引:2,自引:0,他引:2
Triploid plants were grown from the diploid pear scion cultivar (Pyrus pyrifolia Nakai) by anther culture. Androgenic callogenesis occurred at about 10 days after anther excision, and most calli formed within four weeks and stopped growing at less than 1–3 mm in diameter. Androgenic embryogenesis occurred within 8–12 weeks after anther culture. The formed embryos were generally white, globular or heart-shaped. To increase callogenesis and embryogenesis, the effects of cold pre-treatment, light and activated charcoal (AC) on anthers collected from buds were investigated. Cold pre-treatment, dark and lack of AC increased callogenesis more than no cold pre-treatment, light and adding AC. A decisive condition was not found for embryogenesis. The embryogenesis frequency was extremely low and only six embryos were grown. Two embryos expanded greenish cotyledons and developed foliage, and they proliferated when transferred monthly to fresh proliferation medium. The proliferated shoots were rooted and acclimated. Flow cytometric analysis and investigation of the number of chromosomes of regenerants showed that all cells were triploid. 相似文献
68.
Akira P Takagi Satoshi Ishikawa Thuok Nao Sitha Hort Masanori Nakatani Mutsumi Nishida Hisashi Kurokura 《Fisheries Science》2006,72(4):750-754
ABSTRACT: Although the bronze featherback Notopterus notopterus is an important fish in South-East Asia, the population structure has not been investigated. In this study, genetic diversity and population structure of the bronze featherback were examined using nucleotide sequence analysis of the mitochondrial DNA control region for 332 fish collected from Tonle Sap Lake and the Mekong River in Cambodia. The average nucleotide diversity (π) of all samples was 0.033, and the Mekong River samples had higher nucleotide diversity (0.034) than Tonle Sap Lake samples (0.028). The nucleotide diversity between the lake and river samples varied from 0.029 to 0.037. The genetic differentiation between the river and lake populations was also supported by the pairwise F -statistic values and hierarchical analysis of molecular variance, indicating that the Tonle Sap Lake population is genetically isolated from the population in main stream of the Mekong River. 相似文献
69.
Yuichiro Hiraoka Noritsugu Kuramoto Mineko Ohira Masanori Okamura Toru Taniguchi Yoshitake Fujisawa 《Journal of Forest Research》2011,16(6):509-517
Rhus succedanea L. is cultivated in Japan for the wax that can be extracted from its fruits. We determined genetic data for specific traits
associated with wax production (fruit number per cluster, FN, fruit weight, FW, number of clusters per area, CN, and wax content,
WC) in five traditional cultivars and 13 newer clones. Data were collected over 4 years and alternate bearing was observed:
2001 and 2003 were years with high yields; in 2002 and 2004 yields were poor. The restricted maximum likelihood method was
used to calculate (co)variance components for analysis. Broad sense heritability was estimated and ranged from low (FN and
CN) to high (FW and WC) for the traits examined. There were positive genetic correlations between FW and WC and negative ones
between FN and FW throughout the 4 years. Genetic correlations between CN and the other traits were positive in good crop
years and negative in bad crop years. For each assessed clone, the four traits in the 4 years were evaluated using best linear
unbiased predictors (BLUP) of the clonal breeding values. The BLUP scores for both FW and WC exhibited positive correlations
between pairs of years, whereas there were positive BLUP correlations for CN when the high yield and low yield years were
examined separately. The traditional cultivars and the newer clones were also characterized. Some of the clones were better
than the traditional cultivars with regard to wax yield and reliability of production. The trait characteristics and the future
breeding are discussed. 相似文献
70.
Scalbert A Andres-Lacueva C Arita M Kroon P Manach C Urpi-Sarda M Wishart D 《Journal of agricultural and food chemistry》2011,59(9):4331-4348
Considerable information on the chemistry and biological properties of dietary phytochemicals has accumulated over the past three decades. The scattering of the data in tens of thousands publications and the diversity of experimental approaches and reporting formats all make the exploitation of this information very difficult. Some of the data have been collected and stored in electronic databases so that they can be automatically updated and retrieved. These databases will be particularly important in the evaluation of the effects on health of phytochemicals and in facilitating the exploitation of nutrigenomic data. The content of over 50 databases on chemical structures, spectra, metabolic pathways in plants, occurrence and concentrations in foods, metabolism in humans and animals, biological properties, and effects on health or surrogate markers of health is reviewed. Limits of these databases are emphasized, and needs and recommendations for future developments are underscored. More investments in the construction of databases on phytochemicals and their effects on health are clearly needed. They should greatly contribute to the success of future research in this field. 相似文献