Improvement of diagnostic markers for resistance to Globodera pallida and application for selection of resistant germplasms in potato breeding     

Kenji Asano  Etsuo Shimosaka  Yoko Yamashita  Takashi Narabu  Satoshi Aiba  Itaru Sakata  Kotaro Akai  Satoshi Okamoto  Seiji Tamiya 《Breeding Science》2021,71(3):354

Occurrence of pale potato cyst nematode, Globodera pallida (Stone) Behrens, was first recorded in Japan in 2015. Among several control measures, cultivation of resistant potato (Solanum tuberosum L.) varieties is the most effective in cost and environmental impact. As no G. pallida-resistant varieties have yet been developed in Japan, great emphasis is being placed on screening of germplasm possessing the resistance and development of the resistant varieties. In this study, we first improved previously reported DNA markers linked to the G. pallida resistance loci (GpaIV^s_adg and Gpa5) and then used these to screen more than 1,000 germplasms to select several candidate germplasms with resistance. We performed inoculation testing on the selected candidates and identified several resistant germplasms to the Japanese G. pallida population. Furthermore, we developed a simultaneous detection method combining three DNA markers linked to G. pallida and Globodera rostochiensis (Wollenweber) Behrens resistance loci. We validated the ability of C237-I marker to select resistant allele of GpaIV^s_adg and predict the presence of resistance in a Japanese breeding population. Resistant germplasms identified in this study could potentially be used to develop G. pallida-resistant varieties. The marker evaluation methods developed in this study will contribute to the efficient development of resistant varieties.  相似文献   

Cryptic occurrence of <Emphasis Type="Italic">Chattonella marina</Emphasis> var. <Emphasis Type="Italic">marina</Emphasis> in mangrove sediments in Probolinggo,East Java Province,Indonesia     

Ayu-Lana-Nafisyah  Endang-Dewi-Masithah  Kazumi Matsuoka  Mirni-Lamid  Mochammad-Amin-Alamsjah  Shizuka O-hara  Kazuhiko Koike 《Fisheries Science》2018,84(5):877-887

Mangrove forests and adjacent creeks are known to be highly productive estuaries, which are partly supported by benthic microalgae that grow on the sediments. During surveys investigating the microalgal floras of mangrove swamps in the eastern part of Java Island, a mud sample unexpectedly included large numbers of a notorious fish killer, Chattonella-like motile cells, and its resting cysts. These motile cells were established as clonal cultures for further identification and physiological tests. The cysts were examined through palynological and molecular biological means. Identification based on light microscopy and ribosomal RNA gene sequences confirmed that these cells and cysts were Chattonella marina var. marina. While the strains were genetically identical to the temperate strains isolated from Japan and China, temperature experiments showed that the Indonesian strains possessed a high maximum quantum yield of photosystem II even after exposure to 34 °C, a temperature at which the Japanese strain could not survive. Salinity experiments showed adaptation of the strains to a salinity of 15. These findings, together with the discovery of populations of cysts in the mangrove sediment, highlight the tough and unique nature of the Indonesian strains, which are likely adapted to wide fluctuations of temperature and salinity in mangrove swamps, and pose a potential risk to fisheries in Indonesia.  相似文献   

Association of BoLA-DRB3 alleles identified by a sequence-based typing method with mastitis pathogens in Japanese Holstein cows     

Tatsuyuki YOSHIDA  Harutaka MUKOYAMA  Hiroki FURUTA  Yasuko KONDO  Shin-nosuke TAKESHIMA  Yoko AIDA  Motoaki KOSUGIYAMA  Hiroshi TOMOGANE 《Animal Science Journal》2009,80(5):498-509

The association of the polymorphism of bovine leukocyte antigen ( BoLA-DRB3 ) genes identified by the polymerase chain reaction sequence-based typing (PCR-SBT) method with resistance and susceptibility to mastitis caused by pathogenic bacteria was investigated. Blood samples for DNA extraction were collected from 194 Holstein cows (41 healthy cows and 153 mastitis cows including 24 mixed-infection cows infected with 2 or 3 species of pathogens) from 5 districts of Chiba prefecture, Japan. Sixteen BoLA-DRB3 alleles were detected. The 4 main alleles of DRB3*0101 , *1501 , *1201 , and *1101 constituted 56.8% of the total number of alleles detected. Mastitis cows were divided into 2 groups: group 1 with single-infection cows and group 2 with all mastitis cows including 24 mixed-infection cows. The differences in the frequencies of BoLA-DRB3 alleles and the number of cows homozygous or heterozygous for each BoLA-DRB3 allele between healthy cows and the 2 groups of mastitis cows were evaluated. Furthermore, similar comparisons were performed between healthy cows and the 2 groups of mastitis cows for each mastitis pathogen. It was considered that the 4 alleles, namely, DRB3*0101 , *1501 , *1201 , and *1101 had specific resistance and susceptibility to 4 different mastitis pathogens. Thus, DRB3*0101 might be associated with susceptibility to coagulase-negative Staphylococci and Escherichia coli , and DRB3*1501 might be associated with susceptibility to Escherichia coli . However, DRB3*1101 might be associated with resistance to Streptococci and coagulase-negative Staphylococci , and DRB3*1201 , with resistance to Streptococci , Escherichia coli , and Staphylococcus aureus .  相似文献   

Arteriovenous shunts resembling patent ductus arteriosus in dogs: 3 cases     

Yoko Fujii  Takuma Aoki  Hiroshi Takano  Ryokichi Ishikawa  Yoshito Wakao 《Journal of Veterinary Cardiology》2009,11(2):147-151

Three dogs presented for the evaluation of cardiac murmurs were diagnosed with aberrant arteriovenous shunts. All cases demonstrated the following findings: 1) relatively soft continuous murmur loudest at the left heart base resembling patent ductus arteriosus (PDA); 2) shunt flow signals in the pulmonary artery on echocardiography; and 3) no PDA on selective angiography, but evidence of anomalous shunting vessels from thoracic aorta to pulmonary vasculature. An aberrant arteriovenous shunt should be considered when a continuous murmur of relatively small intensity is heard.  相似文献   

High-resolution mapping revealed a 1.3-Mbp genomic inversion in Ssi1, a dominant semidwarf gene in rice (Oryza sativa)     

K. Miura    J. Wu    H. Sunohara    X. Wu    T. Matsumoto    M. Matsuoka    M. Ashikari    H. Kitano 《Plant Breeding》2009,128(1):63-69

Dwarf or semidwarf characters are an important trait for crop breeding as they provide lodging resistance. The rice mutant line DMF-1 has a dm-type semidwarf phenotype and high-lodging resistance controlled by the dominant gene, Short second internode 1 ( Ssi1 ). To elucidate the mechanism of reducing culm length in DMF-1, we sought to identify the Ssi1 gene by positional cloning using the chromosome segment substitution line as a crossing parent. As a result of high-resolution mapping, we found a 1.3-Mbp genomic inversion and a newly arranged gene in the Ssi1 locus. In this study, we report the high-resolution mapping and physical mapping of Ssi1 . We also discuss the possible function of a novel rearranged Ssi1 gene for the dominant dm-type semidwarf phenotype.  相似文献   

Habitat differentiation between sei (Balaenoptera borealis) and Bryde's whales (B. brydei) in the western North Pacific     

Hiroko Sasaki  Hiroto Murase  Hiroshi Kiwada  Koji Matsuoka  Yoko Mitani  Sei‐ichi Saitoh 《Fisheries Oceanography》2013,22(6):496-508

Two closely related baleen whale species, sei and Bryde's whales, in the western North Pacific were studied to identify differences in habitat use. Data were obtained from May to August 2004 and 2005. This study examined the relationship between oceanographic features derived from satellite data and the distribution of sei and Bryde's whales using basic statistics. We investigated oceanographic features including sea surface temperature (SST), sea surface chlorophyll a (Chl‐a), sea surface height anomalies (SSHAs), and depth of the habitat. These two whale species used habitats with different SST, Chl‐a, and SSHA ranges. The 0.25 mg m^?3 Chl‐a contour (similar to the definition of the Transition Zone Chlorophyll Front) was a good indicator that separated the habitats of sei and Bryde's whales. Then generalized linear models were used to model the probabilities that the whale species would be present in a habitat and to estimate their habitat distribution throughout the study area as a function of environmental variables. The potential habitats of the two species were clearly divided, and the boundary moved north with seasonal progression. The habitat partitioning results indicated that SST contributed to the patterns of habitat‐use and might reflect differences in prey species between the two whales. This study showed that the habitats of the sei and Bryde's whales were clearly divided and their potential habitat‐use changed seasonally.  相似文献   

Spatial distribution of Antarctic minke whales (Balaenoptera bonaerensis) in relation to spatial distributions of krill in the Ross Sea,Antarctica     

Hiroto Murase  Toshihide Kitakado  Takashi Hakamada  Koji Matsuoka  Shigetoshi Nishiwaki  Mikio Naganobu 《Fisheries Oceanography》2013,22(3):154-173

The spatial distribution of Antarctic minke whales in the Ross Sea with relation to spatial distributions of their prey – krill – was investigated in this study using generalized additive models (GAMs). Spatial distributions of two species of krill (ice and Antarctic krill) were estimated by GAMs. Three abiotic factors – distance from the continental shelf break (800 m isobaths), the mean temperature and salinity from the surface to 200 m (MTEM‐200 and MSAL‐200), and latitude and longitude – were used as covariates for models of krill. Estimated spatial distributions of krill were then used with other covariates to model the spatial distribution of Antarctic minke whales. In the selected model of Antarctic minke whales, Antarctic krill were more influential than ice krill. The number of Antarctic minke whales increased as the density of Antarctic krill increased to around 1.5 g m^?2. Beyond that, the number of Antarctic minke whales decreased as the density of Antarctic krill increased. High densities of the Antarctic minke whales were estimated along the sea ice edge in the eastern part of the Ross Sea. Specifically, the densities were high in the north of the continental shelf break where low MTEM‐200 and MSAL‐200 and intermediate densities of Antarctic krill were observed. Further data collection is needed to investigate interannual variations and trends in their relationship. The results show that the spatial distribution of Antarctic minke whales is a function of longitude, distance from the shelf break, oceanographic condition (temperature and salinity), and densities of ice and Antarctic krill.  相似文献   

Comparison of the amount of thiotrophic symbionts in the deep-sea mussel <Emphasis Type="Italic">Bathymodiolus septemdierum</Emphasis> under different sulfide levels using fluorescent in situ hybridization     

Masaru Fujinoki  Tomoko Koito  Suguru Nemoto  Mitsugu Kitada  Yoko Yamaguchi  Susumu Hyodo  Hideki Numanami  Nobuyuki Miyazaki  Koji Inoue 《Fisheries Science》2012,78(1):139-146

Various invertebrates inhabiting hydrothermal vents harbor thiotrophic endosymbionts that provide the host with nutrients and are possibly involved in the detoxification of harmful sulfides. In this study, we first determined the partial 16S rRNA gene sequence of the thiotrophic symbiont of the deep-sea mussel Bathymodiolus septemdierum, a dominant species at hydrothermal vents in the Izu–Ogasawara (Bonin) area. We then designed a new probe, Bsob692, for fluorescent in situ hybridization (FISH) using regions completely conserved among thiotrophic symbionts of all bathymodiolin mussels and established the protocol for FISH to compare the distribution and amount of the symbiont using an image analysis program that is commercially available. We compared fluorescent intensity in the gill of the mussels collected at different sites and found a higher intensity in specimens collected from a site with higher sulfide concentration. We also compared mussels reared in the presence and absence of sulfide and found that the former had a higher fluorescent intensity.  相似文献   

Growth and age composition of northern shrimp Pandalus eous estimated by multiple length frequency analysis     

Hiroshi Yamaguchi  Yoko Goto  Noboru Hoshino  Kazushi Miyashita 《Fisheries Science》2014,80(4):665-678

We examined growth of northern shrimp Pandalus eous in the Sea of Japan, off western Hokkaido, to improve estimations of catch-at-age for stock assessment. Multiple length frequency analysis based on length frequency data collected by a scientific research vessel was conducted to examine length-at-age in the shrimp population. Multi-normal distributions estimated using maximum likelihood indicated a good fit to length distributions. AIC values and regression analyses revealed annual growth variation and a decreasing trend in the length at several age classes in the shrimp population. We revised the method for estimating catch-at-age from the age-conversion table (ACT), which is a simple method for age determination, to age–length keys (ALK) calculated from the results of multiple length frequency analysis. Abundant year classes caught successively year after year could be more easily identified from the catch-at-age data computed using ALK than by using ACT. Our results suggested not only that the mean size of commercial landings fluctuated based on changes in age composition but also that a decrease in the length-at-age in the population influenced the consistent size decrease of commercial landings.  相似文献   

Development of a new selective medium for isolation of methicillin-resistant Staphylococcus aureus     

Saito E  Kakita Y  Shimoda H  Shimabukuro S  Saeki K  Shimizu A  Kawano J 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(9):1195-1197

A new selective medium containing cephem antibiotics was developed for isolation of methicillin-resistant Staphylococcus aureus (MRSA). MRSA colonies on a medium containing ceftazidime (CAZ) were most easily identifiable and a medium containing cefoperazone (CPZ) was superior in suppressing the growth of other bacteria. With the medium containing a couple of CAZ and CPZ, MRSA and methicillin-resistant coagulase-negative staphylococci (MRCNS) were detected from 2 and 1 of 15 chicken meat samples respectively. The MRSA and MRCNS recovery test showed that the medium was effective for MRSA isolation, suppressing the growth of other bacteria efficiently. These results suggested that the medium containing a couple of CAZ and CPZ was useful for MRSA detection from foods and animals.  相似文献