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101.
Malik Ashiq Rabbani Yoshie Murakami Yasuhisa Kuginuki Kenji Takayanagi 《Genetic Resources and Crop Evolution》1998,45(4):307-316
Genetic diversity of 30 radish (Raphanus sativus L.) accessions was investigated at the phenotypic level with morphological characters and at the DNA level using the random amplified polymorphic DNA (RAPD) technique. Thirty-six morpho-physiological traits were recorded from seedling stage to harvest. The 31 primers used generated 202 RAPD bands, of which 158 (78.2%) were polymorphic. Multivariate procedures were used to classify the germplasm on the basis of phenotypic traits and RAPD fragments. Dendrograms were generated for the Euclidean distance from the morphological data and the Nei's genetic distance from the RAPD markers. Phenotypically, all the accessions were classified into four major groups corresponding to the different forms of cultivated radish. The morphological diversity existing within each of these groups suggested that they should be discriminated into the three botanical convarieties, sativusT (large-rooted), caudatus (pod-type) and oleifer (oilseed-type). Clustering of the accessions did not show any pattern of association between the morphological characters and the collection sites. Instead, landrace groups were associated with their morphological similarities and horticultural uses. On the other hand, the intra-specific genetic relationships of several accessions based on RAPD analysis were related primarily to their collection sites rather than to their phenotypic affinities. The level of polymorphism exhibited by the various convarieties could be exploited in genetic mapping populations to tag economically important traits. These genotypes also could serve as a useful germplasm source for root, leaf, pod and seed. This preliminary study of traditional radish landraces from Pakistan provides useful information regarding their horticultural potential. 相似文献
102.
Amal Biswas Biswajit K. Biswas Junichi Ito Osamu Takaoka Norishige Yagi Syunsuke Itoh Kenji Takii 《Fisheries Science》2011,77(4):615-621
This study was carried out to investigate whether expensive enzyme-treated fish meal (EFM) can be partially replaced by soybean
meal (SM) or enzyme-treated SM (ESM) without compromising the growth of captive-raised Pacific bluefin tuna (PBT) juveniles.
Five fish diets were tested: EFM (control) and EFM in which 10 or 20% of the EFM was replaced with either ESM or SM (ESM10, ESM20, SM10 and SM20, respectively). The respective diets were provided to 28-day-old PBT juveniles (mean body weight approx. 0.38 g) stocked
randomly in 15-m3 tanks (276 juveniles per tank; two tanks per treatment) for 12 days. The final mean body weight of PBT juveniles on diets
EFM, SM10, and SM20 was significantly higher than that of juveniles on diet ESM20. Although daily feeding rate was significantly higher in the ESM and SM groups, feed efficiency (FE) was significantly higher
in the EFM group; there was no significant difference between juveniles fed diets EFM and SM10. Protein and phosphorus retention efficiency were significantly lower in the ESM20, and ESM20 and EFM groups, respectively. Phosphorus discharge was significantly lower in the SM groups. The results demonstrate that
10% SM (11% EFM replacement) can be included in EFM without compromising the growth performance of PBT juveniles. 相似文献
103.
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 (GpaIVsadg 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 GpaIVsadg 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
104.
Kenji Minami Hiroki Yasuma Naoki Tojo Shin-ichi Fukui Yusuke Ito Takahiro Nobetsu Kazushi Miyashita 《Fisheries Science》2010,76(5):729-736
Sustainable management of the kelp forests of the Shiretoko Peninsula, a World Natural Heritage site, is necessary due to
kelp’s ecological and economic importance. The objectives of this study were to estimate the area of kelp forests and to clarify
their spatial characteristics in coastal waters of the Shiretoko Peninsula. Data on the presence/absence and thickness of
kelp forests were collected via acoustic observation on transects over about 80 km using an echosounder at 200 kHz. Acoustic
data were geostatistically interpolated, and the areas covered by kelp forests were estimated. Differences in kelp distribution
between the eastern and western sides of the peninsula were compared. The total area of kelp forest was 3.88 km2 (eastern area: 3.49 km2; western area: 0.39 km2). The range of thickness of the kelp forests was 34–91 cm. Many kelp forests in the eastern area were thick (>78 cm) and
distributed continuously, while kelp forests in the western area were sparsely distributed. 相似文献
105.
Kenji Nohara Hiroyuki Takeuchi Tatsuo Tsuzaki Nobuaki Suzuki Osamu Tominaga Tadahisa Seikai 《Fisheries Science》2010,76(1):75-81
Sequence analysis based on the anterior part of the mitochondrial DNA control region was carried out to reveal the genetic diversity, stock structure, and historical demography of the red tilefish. Nucleotide sequences of 388 bp in length were determined for 280 individuals taken from eight localities. The molecular diversity, haplotype diversity, and nucleotide diversity were relatively high (average h = 0.929 ± 0.011; average π = 0.008 ± 0.005). The mismatch distribution was not significantly different from the expected distribution for a rapidly expanding population (P = 0.453). The minimum spanning network connecting with full-sequence haplotypes contained star-like topologies derived from multiple ancient lineages, supporting the mismatch distribution analysis. No significant genetic differentiation was observed among eight localities (maximum pairwise F ST = 0.023, reduced-sequence data set). Our results suggest a large panmictic population of the red tilefish along the coast of Honshu to the East China Sea. 相似文献
106.
Saitoh Kanae Yoshimura Tomohiro Sun Luchuanyang Yang Min Wang Yao Taniyama Shigeto Hara Kenji Murayama Fumihito Nikawa Takeshi Tachibana Katsuyasu Hirasaka Katsuya 《Fisheries Science》2020,86(1):187-196
Fisheries Science - Fish oil containing omega-3 polyunsaturated fatty acids (PUFA) attenuates chronic inflammation found in obesity, leading to a reduction in insulin resistance. The effect of fish... 相似文献
107.
Seko Takuya Imamura Shintaro Ishihara Kenji Yamashita Yumiko Yamashita Michiaki 《Fisheries Science》2020,86(1):171-179
Fisheries Science - The novel organic selenium compound, selenoneine, is found in the blood of tuna and has metal-binding activity. In this report, selenoneine displays tyrosinase inhibitory... 相似文献
108.
Suzuki Toshiyuki Kamiyama Takashi Okumura Yutaka Ishihara Kenji Matsushima Ryoji Kaneniwa Masaki 《Fisheries Science》2009,75(4):1039-1048
Fatty-acid esters of dinophysistoxin-1 (DTX1) in scallops Patinopecten yessoensis, mussels Mytilus coruscus, and toxic dinoflagellate Dinophysis species, collected from Japanese seawater, were analyzed by liquid-chromatography mass spectrometry (LC–MS). Precursor ion
monitoring, multiple reaction monitoring for 18 fatty-acid esters of DTX1, and full-scan MS/MS spectra obtained with a hybrid
triple–quadrupole linear-ion-trap mass spectrometer showed that 14:0, 16:0, and 16:1 esters were the most abundant 7-O-acyl-DTX1 analogues in bivalves. Fatty-acids esters formed by conjugations at hydroxyl positions other than the 7-position
of DTX1 were not detected in the bivalves. DTX1 and okadaic acid-16:0 fatty-acid esters have been reported as the most abundant
ester in bivalves in several previous studies; however, we found that 7-O-16:1-DTX1 was the most abundant ester in some mussels in which 16:1 was more dominant than 16:0 in the free fatty-acid profile.
Comparison between 7-O-acyl-DTX1 and free fatty-acid profiles in the same bivalve samples suggests that polyunsaturated fatty acids are selectively
excluded in enzymatic acylation of DTX1. No 7-O-acyl-DTX1 was detected in any single-cell isolates of D. fortii, D. acuminata, D. mitra, D. norvegica, D. tripos, D. infundibulus, and D. rotundata. 相似文献
109.
Inwoo Bae Kiyoshi Osatomi Asami Yoshida Atsuko Yamaguchi Katsuyasu Tachibana Tatsuya Oda Kenji Hara 《Fisheries Science》2009,75(3):765-770
A translucent collagen gel was formed from a transparent acidic solution of red stingray collagen by adjusting to physiological
ionic strength and pH in phosphate buffer and then incubating at 25–37°C. During fibril formation from red stingray collagen,
the turbidity increased when the NaCl concentration was increased at constant pH and the rate of fibril formation was accelerated
by higher pH or lower NaCl concentration. The T
m of red stingray collagen fibrillar gel was estimated as 44.3 ± 3.5°C, which was higher than that of the collagen solution,
33.2°C. In addition, red stingray collagen gel maintained its shape without melting and was suitable for culture of mouse
stromal cells at 37°C. 相似文献
110.
Ryo TAKEUCHI Satoshi TAKAGI Kenji HOSOYA Hiroshi OHTA Takaharu ITAMI Masahiro OKUMURA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(11):1740
Canine gastroesophageal intussusception (GEI) is a rare and life-threatening condition that requires prompt diagnosis and treatment. A 19-day-old Siberian Husky with a 4-day history of regurgitation was diagnosed with GEI based on the findings of computed tomography (CT) performed without anesthesia. Endoscopic reduction of intussusception was impossible; thus, surgical reduction by traction of the duodenum was performed. CT revealed improvement of megaesophagus 82 days postoperatively. Eleven months postoperatively, fluoroscopy showed recovery to nearly normal esophageal motility. Two years postoperatively, no clinical signs were reported. CT is useful to diagnose GEI in neonate puppies with poor abdominal fat and to assess the gastric edema and the anatomical association of stomach with other organs. Fluoroscopy is helpful for evaluating postoperative esophageal motility. 相似文献