Principles and approaches to abate seabird by-catch in longline fisheries   总被引：2，自引：0，他引：2  

Eric Gilman  Nigel Brothers  & Donald R. Kobayashi 《Fish and Fisheries》2005,6(1):35-49

Mortality in longline fisheries is a critical global threat to most albatross and large petrel species. Here we identify key principles and approaches to identify and achieve broad use of effective seabird by‐catch avoidance methods. Despite the availability of highly effective and cost‐saving seabird avoidance methods, few longline fleets employ them. Given the political context and capacity of management authorities of the majority of longline fisheries, it is critical to identify seabird avoidance strategies that are not only highly effective, but are also economically viable and commercially practical. Adoption of an international performance standard for longline baited hook–sink rate, and prescribing minimum gear weighting designs that meet this standard that are achievable by all longline fisheries, would be an important step forward towards resolving low use of seabird avoidance methods by vessels, including those in illegal, unregulated and unreported fisheries. Due to differences between fleets, no single seabird avoidance measure is likely to be effective and practical in all longline fisheries. Therefore, testing of seabird avoidance methods in individual fleets is needed to determine efficacy and economic viability. Longline fishers should directly participate in these trials as they have a large repository of knowledge and skills to effectively develop and improve seabird by‐catch avoidance techniques, and this provides industry with a sense of ownership for uptake of effective by‐catch reduction methods. Establishing protected areas containing seabird colonies and adjacent waters within a nation's EEZ can be an expedient method to address seabird by‐catch. However, establishing high seas marine protected areas to restrict longline fishing in seabird foraging areas, which would require extensive and dynamic boundaries and large buffer zones, may not be a viable short‐term solution because of the extensive time anticipated to resolve legal complications with international treaties, to achieve international consensus and political will, and to acquire requisite extensive resources for surveillance and enforcement. Analysis of results of research on seabird avoidance methods reveals that the most reliable comparisons of the efficacy of alternative strategies are from comparing the effectiveness of methods tested in a single experiment. Benefits from standardizing the reporting of seabird by‐catch rates to account for seabird abundance are described. To provide the most precise inputs for seabird population models, estimates of seabird mortality in longline fisheries should account for seabird falloff from hooks before hauling, delayed mortality of seabirds caught but freed from gear, and mortality caused by hooks discarded in offal.  相似文献   

Narthecium asiaticum Maxim. Poisoning of grazing cattle: observations on spontaneous and experimental cases     

K Suzuki  M Kobayashi  A Ito  M Nakgawa 《The Cornell veterinarian》1985,75(2):348-365

A total of 39 Holstein cattle were grazed in tracts of wild grassland on account of shortage in pasture grass. Twenty-nine cattle were affected and 26 of them died during a 21-day period. The main signs were depression, anorexia, ascites, and oliguria. There was elevated serum urea nitrogen and sugar and protein in the urine. Pathological examination revealed turbid swelling of the kidney, an increase in the amount of fluid in the body cavity, edema in the perirenal adipose tissue and hemorrhage in various visceral organs and tissues. Histologically, acute tubular necrosis in the kidney, hypoplasia of the erythroblast series in the bone marrow, atrophy and degeneration of the lymphatic tissue and focal necrosis of the liver were observed in many of the cattle. Among cows experimentally fed Narthecium asiaticum Maxim., Polygonum sachalinense Fr. Schum., and Vitis coignetiae Pulliat which were presumed to have been ingested in large amounts by grazing cattle in the field, the cows fed N. asiaticum revealed the clinical, biochemical and pathological changes similar to those noticed in naturally affected cattle. Cows fed P. sachalinense and V. coignetiae showed no distinct systemic symptoms except transient anorexia and hypothermia.  相似文献   

Seed productivity test of CMS lines of Japanese bunching onion (Allium fistulosum L.) possessing the cytoplasm of a wild species, A. galanthum Kar. et Kir.     

Ken-ichiro Yamashita  Yosuke Tashiro 《Euphytica》2004,136(3):327-331

In a previous study, we developed male sterile lines of Japanese bunching onion (Allium fistulosum L.) possessing the cytoplasm of a wild species, A. galanthum Kar. et Kir., by backcrossing. To evaluate seed productivity of the male sterile lines in practise, they were crossed with the male fertile line, cultivar 'Kujyo', using honeybees as pollinators under field conditions. The number of florets and seeds per inflorescence, seed set and seed germination of the material were investigated. Although variation was observed among the male sterile lines, there were several lines having seed productivity equal to cultivar 'Kujyo'. Our data demonstrate that the male sterile lines of A. fistulosum possessing the cytoplasm of A. galanthum are useful as seed parents for the commercial F seed production of A. fistulosum.  相似文献   

Characterization of segregation distortion on chromosome 3 induced in wide hybridization between indica and japonica type rice varieties   总被引：6，自引：0，他引：6  

S. Matsushita  T. Iseki  Y. Fukuta  E. Araki  S. Kobayashi  M. Osaki  M. Yamagishi 《Euphytica》2003,134(1):27-32

We previously surveyed chromosomal regions showing segregation distortion of RFLP markers in the F₂ population from the cross between a japonica type variety ‘Nipponbare’ and an indica type variety ‘Milyang23’, and showed that the most skewed segregation appeared on the short arm of chromosome 3. By comparison with the marker loci where distortion factors were previously identified, this region was assumed to be a gametophytic selection-2 (ga2) gene region. To evaluate this region, two near isogenic lines (NILs) were developed. One NIL had the ‘Nipponbare’ segment of this region on the genetic background of ‘Milyang23’ (NIL9-23), and the other NIL had the ‘Milyang23’ segment on the genetic background of ‘Nipponbare’ (NIL33-18). NIL9-23 and ‘Milyang23’, NIL33-18 and ‘Nipponbare’, and ‘Nipponbare’ and ‘Milyang23’ were respectively crossed to produce F₁ and F₂ populations. The F₁ plants of NIL9-23 × ‘Milyang23’ and NIL33-18 × ‘Nipponbare’ showed high seed fertility and the same pollen fertility as their parental cultivars, indicating that ga2 does not reduce seed and pollen fertility. Segregation ratio of a molecular marker on the ga2 region in the three F₂ populations was investigated to clarify whether segregation distortion occurred on the different genetic backgrounds. Segregation distortion of the ga2 region appeared in the both F₂ populations from the NIL9-23 and ‘Milyang23’ cross (background was ‘Milyang23’ homozygote) and the ‘Nipponbare’ and ‘Milyang23’ cross (background was heterozygote), but did notin the F₂ population from the NIL33-18 and ‘Nipponbare’ cross (background was ‘Nipponbare’ homozygote). This result indicates that ga2 interacts with a ‘Milyang23’ allele(s) on the different chromosomal region(s) to cause skewed segregation of the ga2 region. In addition, segregation ratio was the same between the F₂ populations from NIL9-23 × ‘Milyang23’ and ‘Nipponbare’ × ‘Milyang23’ crosses, suggesting that the both genotypes, ‘Milyang23’ homozygote and heterozygote, of gene(s) located on the different chromosomal region(s) have the same effect on the segregation distortion. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Two male sterility-inducing cytoplasms of beet (Beta vulgaris) are genetically distinct but have closely related mitochondrial genomes: implication of a substoichiometric mitochondrial DNA molecule in their evolution     

Yasuyuki Onodera  Takumi Arakawa  Rika Yui-Kurino  Masayuki P. Yamamoto  Kazuyoshi Kitazaki  Shigehiko Ebe  Muneyuki Matsunaga  Kazunori Taguchi  Yosuke Kuroda  Shiko Yamashita  Tomoyuki Sakai  Toshiro Kinoshita  Tetsuo Mikami  Tomohiko Kubo 《Euphytica》2015,206(2):365-379

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Antitumor activity of compounds isolated from leaves of Eriobotrya japonica   总被引：3，自引：0，他引：3  

Ito H  Kobayashi E  Li SH  Hatano T  Sugita D  Kubo N  Shimura S  Itoh Y  Tokuda H  Nishino H  Yoshida T 《Journal of agricultural and food chemistry》2002,50(8):2400-2403

In a search for possible antitumor agents from natural sources, megastigmane glycosides and polyphenolic constituents isolated from the leaves of Eriobotrya japonica (Rosaceae) were found to inhibit the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced activation of Epstein-Barr virus early antigen in Raji cells. Roseoside and procyanidin B-2 were among the active compounds found in an in vitro assay; these compounds were further assessed for antitumor activity in vivo in a two-stage carcinogenesis assay on mouse skin. Roseoside significantly delayed carcinogenesis induced by peroxynitrite (initiator) and TPA (promoter), and its potency was comparable to that of a green tea polyphenol, (-)-epigallocatechin 3-O-gallate, in the same assay.  相似文献   

Response of denitrifying communities to successive soil freeze–thaw cycles     

Yosuke Yanai  Koki Toyota  Masanori Okazaki 《Biology and Fertility of Soils》2007,44(1):113-119

The effect of soil freeze–thaw cycles on the denitrification potential was examined based on the C₂H₂ inhibition method. The gross N₂O production curve of the soil sample (incubation with C₂H₂) showed minor changes between the freeze–thaw treatment and the unfrozen control. However, kinetics analysis revealed that the initial production rate, an indicator of the population density of denitrifying communities, decreased (P = 0.043) and the specific growth rate constant, an indicator of the activity of denitrifying communities, increased (P = 0.039) as a result of the freeze–thaw cycles in five of six soil samples examined. The increase in the specific growth rate constant suggested the stimulation of the activity of denitrifying communities that survived after the freeze–thaw cycles and may explain the minor suppression on the gross N₂O production in spite of decreasing the population density of denitrifying communities that was suggested by the initial production rate. The net N₂O production curve of the soil sample (incubation without C₂H₂) showed a remarkable change in one out of six soil samples, and in that one soil sample, N₂O release to the atmosphere was largely stimulated (7.6 times) by the freeze–thaw cycles. However, the stimulation of the N₂O release by the freeze–thaw cycles was even observed in two other selected soil samples (4.6 and 1.8 times), suggesting that an imbalance in the N₂O-producing and N₂O-reducing activities of denitrifying communities might complementally explain the N₂O release stimulated by the freeze–thaw cycles.  相似文献   

Radiocesium transfer from Andosols to brown rice in the northern and northwest areas of Tochigi Prefecture,in the first 3 years following the 2011 Fukushima Daiichi nuclear power plant accident     

Satoshi Suzuki  Tsutomu Imura  Yasuo Kobayashi  Masao Usui  Naruo Miyazaki  Toshio Sano 《Soil Science and Plant Nutrition》2020,66(3):515-526

ABSTRACT

Following the Fukushima Daiichi Nuclear Power Plant accident of 2011, the potential for radiocesium transfer from contaminated soils, such as Andosols, to agricultural crops became a significant concern. Andosols account for up to 70％ of paddy soils in the northern and northwest areas of Tochigi Prefecture, where the radiocesium concentration is 1000 Bq kg^?1 or greater in the soil of some fields. The present study was carried out in order to determine the phytoavailability of radiocesium in Andosols by comparing it with that of gray lowland soils in the first 3 years following the accident. The transfer factor (TF) tended to be higher in Andosols than in gray lowland soils, leading to higher radiocesium concentrations in brown rice grown in Andosols. The exchangeable potassium (Ex-K₂O) in Andosols was highly and negatively correlated with TF, followed by clay. The Ex-K₂O value was positively correlated with the clay/total carbon (T-C) value, suggesting that a high T–C ratio could weaken K₂O adsorption on clay mineral sites; hence, the low clay/T-C values can partially explain the relatively large TF values of Andosols. Samples with Ex-K₂O contents less than 200 mg kg^?1 and with low clay/T-C values showed striking decreases in TF values from 2011 to 2012. However, the decrease from 2012 to 2013 was quite small; radiocesium in these samples was potentially available for rice uptake for a long time, likely due to the reversible adsorption and fixation characteristics of allophane. Most gray lowland soil samples showed very low TF values over the 3 years of the study, except for those with TF values greater than 0.1 due to low Ex-K₂O and clay contents; the geometric mean (GM) value of TF was below 0.01 in 2012. The extraction of exchangeable radiocesium (Ex-Cs) with a 1 mol L^?1 ammonium acetate solution may not be an appropriate method for explaining the variability in radiocesium TF in Andosols. This is because the Ex-Cs value was significantly correlated with Ex-K₂O in Andosols, but not in gray lowland soils, indicating that Ex-K₂O explained this variability in relation to Ex-Cs.  相似文献   

Cycloamylose (cyclodextrin) glucanotransferase degrades intact granules of potato raw starch     

Yamamoto K  Zhang ZZ  Kobayashi S 《Journal of agricultural and food chemistry》2000,48(3):962-966

Cycloamylose (cyclodextrin) glucanotransferase (EC 2.4.1.19, CGTase) originated from Bacillus macerans degraded intact granules of potato raw starch and converted them into cyclodextrins (CDs). The degradation required sufficient stirring of starch-CGTase suspension. The morphology of the degraded starch granules was unique; that is, the inner part of the granules was observed by scanning electron microscope to be more susceptible to CGTase than the outer part. Effects of pH, temperature, starch concentration, and enzyme amount on CD production were studied.  相似文献   

Biological dinitrogen fixation and soil microbial biomass carbon as influenced by free-air carbon dioxide enrichment (FACE) at three levels of nitrogen fertilization in a paddy field   总被引：3，自引：0，他引：3  

Mozammel M. Hoque  Kazuyuki Inubushi  Shu Miura  Kazuhiko Kobayashi  Han-Yong Kim  Masumi Okada  Shingo Yabashi 《Biology and Fertility of Soils》2001,34(6):453-459

An experiment was conducted in an Andosol paddy field in Shizukuishi (Iwate Prefecture, Japan) to determine the effects of free-air CO₂ enrichment (FACE) on biological N₂-fixation activity and soil microbial biomass C at three levels of N application. Rice (Oryza sativa L. cv. Akitakomachi) plants were grown under ambient CO₂ or FACE (ambient +200 µmol mol^-1 CO₂) conditions throughout the growing season with each treatment having four replicated plots. Three levels of N fertilizer (high, standard and low; 15, 9 and 4 g N m^-2, respectively) were applied to examine the effect of different N availability under both CO₂ conditions. Soil samples were collected at four different times from upper and lower soil layers (0-1-cm and 1-10-cm soil depths, respectively) and analysed for biological N₂-fixation (BNF) activity and microbial biomass C (MBC) by the acetylene reduction and chloroform fumigation-extraction methods, respectively. The amounts of chlorophyll-type compounds (Chls), an index of algal growth, and soil available C were also determined. Compared to the ambient CO₂ treatment, the FACE treatment had significantly higher BNF activity in both the upper and lower soil layers at ripening only in low-N soil and at harvest at all three levels of N fertilization rates. MBC was significantly increased by FACE in both the upper and lower soil layers from the middle to later period of the growing season compared to the ambient CO₂ treatment. The FACE treatment increased the Chls in the upper soil layers at ripening only in low-N soil and at harvest at all three levels of N fertilization rates. The amount of soil available C was not significantly different between FACE and ambient CO₂ treatments in both the upper and lower soil layers throughout the cropping season. From these results it can be concluded that the FACE treatment had a significantly positive influence on BNF activity, MBC and Chls at different levels of N fertilization rates in paddy field during the cropping season.  相似文献