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741.
The distribution of aluminum components in cross sections of pulp fibers for alum-treated handsheets was successfully measured by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis. In this case, gas-phase osmium coating of paper samples is necessary for the samples to have improved stability to long-term irradiation by electron beams at high magnification during the SEM-EDX measurements. The EDX line-analysis method was superior to the elemental mapping image method in the quantification of aluminum components. According to the SEM-EDX measurement for handsheets prepared from a pulp suspension by adding 2% (on dry weight of pulp) aluminum sulfate, the aluminum components were distributed almost homogeneously in the cross sections of pulp fibers. Aluminum species with smaller sizes than those of A1(OH)3 flocs could probably penetrate the pulp fibers. Thus, aluminum components present only at the pulp fiber surfaces may contribute to retention of colloidal substances in pulp suspensions. From this aspect, a large amount of aluminum components present in the inside pulp fibers may be wasted.This report was presented at the 49th annual meeting of the Japan Wood Research Society at Tokyo, April 1997 相似文献
742.
Nobuto Fukuda Michael J. Miller Jun Aoyama Akira Shinoda Katsumi Tsukamoto 《Fisheries Science》2013,79(3):425-438
The pigmentation stages of Anguilla japonica were classified from the glass eel to yellow eel stage using 412 wild-caught eels from Hamana Lake and detailed developmental observations of 10 laboratory-reared eels. The sequential appearance of pigment was similar to that in A. anguilla, except for delayed pigment formation on the nerve cord of A. japonica. The general classification of pigmentation stages (VA–VIB) in A. anguilla was applicable to A. japonica, but the VB stage could be separated into two stages (VB1, VB2) in A. japonica. The completion of guanine deposition on the intra-abdominal membrane may be a trait to discriminate the yellow eel stage (VII) from the VIB stage. In natural conditions, wild-caught 0-age eels (n = 3,298) did not increase in size and retained a slender body form until VIA4, and then became thicker during VIB. The transition between body forms and growth may correspond to their ecological change from using passive transport in glass eels with tidal flow into rivers, to their settlement and further movements of elvers upstream. Considering this behavioral transition and pigmentation progression, it is proposed that the terms "glass eel" and "elver" could be defined as stages VA–VIA4 and VIB, respectively. 相似文献
743.
Akira?KawakamiEmail author Naoki?Kato Takahide?Sasaya Keisuke?Tomioka Hiroyoshi?Inoue Atsushi?Miyasaka Kazuyuki?Hirayae 《Journal of General Plant Pathology》2015,81(4):324-327
Ear rot with white or pink mold was found on corn (Zea mays L.). A species of Fusarium, not registered previously as a pathogen causing Gibberella ear rot of corn in Japan, was isolated from the rotted ear. The isolates, identified as F. asiaticum based on morphological characteristics and nucleotide sequences, caused white or pink mold on corn ear after inoculation. Moreover, the 3-acetyl deoxynivalenol chemotype and the nivalenol chemotype were found in the isolates. We propose to include F. asiaticum as one of the pathogens causing Gibberella ear rot of corn in Japan. 相似文献
744.
Garden asparagus (Asparagus officinalis L.) is an economically important plant. This species is dioecious, and male plants are considered to be more desirable than females due to their higher yields. To reduce the time required for asparagus breeding, molecular marker techniques have been employed to identify sex-linked DNA markers. In the present study, we converted the male-specific random amplified polymorphic DNA marker T35R54-1600 into a sequence tagged site marker. We cloned a male-specific DNA fragment amplified with the T35R54 primer and determined the sequence of the fragment. The size of T35R54-1600 is 1,586 bp, and this fragment is not homologous to known sex-linked BAC sequences, indicating that this fragment is a new sex-linked region. Within this fragment, we designed the primer pair ‘MSSTS710’ to amplify a 710 bp region. This marker could be used to identify the sex of eight cultivars of A. officinalis: ‘Mary Washington 500W’, ‘UC157’, ‘Harumachi Green’, ‘Super Welcome’, ‘F4’, ‘Pacific 2000’, ‘F2’ and ‘Backlim’. We also analyzed the applicability of this marker to two dioecious Asparagus species, A. schoberioides and A. kiusianus, which are cross-compatible with A. officinalis. Although male-specific DNA fragments of two dioecious Asparagus species, A. schoberioides and A. kiusianus, were generated using the existing male-specific marker Asp1T7sp, no amplicon was obtained using the MSSTS710 marker. Since MSSTS710 can be employed for sex identification only in A. officinalis and not in closely related Asparagus species, the DNA region around the MSSTS710 marker must be variable among Asparagus species. 相似文献
745.
Akira Kawaguchi Koji Tanina 《European journal of plant pathology / European Foundation for Plant Pathology》2014,140(3):399-406
Clavibacter michiganensis subsp. michiganensis (CMM) strains collected in nine different prefectures in Japan were fingerprinted by inter-simple sequence repeats–polymerase chain reaction (PCR) and repetitive sequence–based PCR. Forty-three CMM strains corresponded to 22 DNA fingerprinting patterns, indicating that the CMM population in Japan has high genetic diversity. Tomato plants were inoculated with CMM by two different methods: defoliation using infected scissors and planting in soil containing infected plant debris. Defoliation resulted in a larger number of diseased plants, disease developed earlier, and plants survived for significantly fewer days. Upon planting in the infected soil, 33.3 % of plants were infected and 6.7 % were diseased, i.e., 20.1 % of infected plants developed disease symptoms. These results indicate that some plants are infected with CMM through plant debris in the soil as the primary inoculum and most infected plants maintain latent infection. Thus, growers may unwittingly carry out disbudding and defoliation of latently infected plants, resulting in secondary inoculum. 相似文献
746.
Akira Kawaguchi 《Journal of General Plant Pathology》2014,80(5):435-442
Bacterial spot, caused by Xanthomonas arboricola pv. pruni, is the most important disease that affects peach production in Okayama Prefecture, Japan. Currently, this disease is managed mainly with copper compounds applied at two stages, before flowering and after harvesting, or with antibiotics applied in May and June. Here we identified the disease risk factors that affect peach at harvest and developed a disease-forecasting model to help growers decide when to apply bactericides. The model was based on parameters for weather data collected for September and October of 2001 through 2012 and for April, May, and June of 2002 through 2013, combined with data on bacterial leaf spot incidence obtained from 28 to 30 fields per year in August from 2001 to 2012 and in May to July from 2002 to 2013. The model, developed using a logistic regression analysis, included the percentage of fields with a bacterial spot incidence (BSI) ≥1 % in mid-August of the previous season and the number of rainy days (≥5 mm/day) during the current June as predictors, and explained 75.0 % of the variability. These results suggest that the previous season’s BSI and weather variables in the present season can be used to predict the risk of bacterial spot. 相似文献
747.
748.
Orchids are commercially important plants with flowers that are unique and very specialized in shape and color. The flowers consist mostly of sepals, lateral petals, lip (labellum) and column, and are zygomorphic and resupinate. Whereas most orchid species have petaloid tepals in the first and second whorls, Habenaria radiata has a flower with greenish sepals and white lateral petals and lip. ‘Hishou’, one of the cultivars of H. radiata, is a floral homeotic mutant and has a petaloid median sepal and lip-like lateral sepals in the first whorl. Additionally, this cultivar often has non-resupinate flowers whereas wild-type H. radiata flowers are resupinate. In the present study, we investigated the genetic inheritance of these characters in the ‘Hishou’ cultivar by crossing it with wild-type plants. Some intraspecific hybrids, which were confirmed by PCR-RFLP analysis, had flowers with a petaloid median sepal and lip-like lateral sepals in the first whorl, indicating that these were dominant characters. Since the remainder of the intraspecific hybrids had wild-type flowers, these characters must be heterozygous in ‘Hishou’ plants. Although ‘Hishou’ plants had non-resupinate flowers, intraspecific hybrid flowers were resupinate, even though they had the petaloid median sepal and lip-like lateral sepals. This result indicates that non-resupination must be a recessive character. Since sepal-petalization and triple lip characters of ‘Hishou’ inherited dominantly, these characters can be utilized for the breeding of Habenaria species by intra- and interspecific crosses. 相似文献
749.
We have established an analysis method for some free amino acids (FAAs), as well as taurine (Tau), anserine (Ans) and carnosine (Car), in a fresh biopsy sample from cattle muscle. A series of model biopsy samples, corresponding to the mixtures of lean meat, fat and connective tissue, was prepared and showed high correlation coefficients between the compound concentration and the 3‐methylhistidine (3‐MeHis) content derived from hydrolysis of the biopsy sample (r = 0.74–0.95, P < 0.01). Interference from blood contamination could not be neglected, because the concentration of some FAAs in blood was comparable to that in muscle. However, it was possible to control the contamination of Tau, Ans, Car, glutamic acid, glutamine, asparatic acid and alanine to less than 5.0% when the blood contamination was controlled to less than 23%.These results suggest the necessity of measuring 3‐MeHis as an index of lean meat and hemoglobin as an index of blood contamination when compounds in muscle biopsy samples are evaluated. We have carried out a series of these analyses using one biopsy sample and reveal differences in Tau, Ans, Car and some FAAs in beef muscle after different feeding regimes. 相似文献
750.
Kohji NAGAHORI Shigehisa IWAMOTO Akira MARUYAMA Shingo SUZUKI Kazuyoshi HOSOMICHI Takashi SHIINA Hiromi HARA Yutaka YOSHIDA Kei HANZAWA 《Animal Science Journal》2010,81(4):513-518
In the current study, we describe four novel members of the 90 kDa heat shock protein (HSP90) family expressed in Japanese quail, Coturnix japonica. The coding regions of the genes, CjHSP90AA1, CjHSP90AB1, CjHSP90B1 and CjTRAP1, exhibited more than 94% similarity to their related genes in chicken. The putative proteins encoded by these quail genes contained motifs considered essential for HSP90 gene function. In addition, the predicted proteins were more similar to HSP90AA1, HSP90AB1, HSP90B1 and TRAP1 proteins expressed in vertebrates than they were to other members of the HSP90 family. Exon numbers of CjHSP90AA1 (11), CjHSP90AB1 (12) or CjTRAP1 (18) are the same as the chicken and mammalian orthologs. Furthermore, gene order in the regions surrounding CjHSP90AB1 and CjTRAP1 has been preserved, providing evidence that the genomic regions were orthologous to HSP90‐containing regions in the chicken genome. The promoter regions of the genes also contained conserved motifs identified in related genes of chicken. However, the nucleotide sequences of the 5′‐flanking region of these genes were highly polymorphic. We also found that CjHSP90AA1 exhibited a robust response to heat shock treatment. Taken together, the data suggest that CjHSP90AA1, CjHSP90AB1, CjHSP90B1 and CjTRAP1 encode orthologs of HSP90AA1, HSP90AB1, HSP90B1 and TRAP1, respectively. 相似文献