Eastern little tuna,Euthynnus affinis (Cantor, 1849) mature and reproduce within 1 year of rearing in land‐based tanks          下载免费PDF全文

Ryosuke Yazawa  Yutaka Takeuchi  Kenta Satoh  Yuri Machida  Kotaro Amezawa  Naoki Kabeya  Yukinori Shimada  Goro Yoshizaki 《Aquaculture Research》2016,47(12):3800-3810

Eastern little tuna (ELT, Euthynnus affinis) is expected to see use as a novel aquaculture species due to its rapid growth and high economic value. In this study, closing of the complete life cycle of ELT in land‐based tanks was successfully carried out. Seed production of a first generation (F1) derived from wild‐caught ELT broodstock was conducted in 2010, 2011 and 2012. Survival percentages of F1 ELT at 365 days post hatching for the 2010, 2011 and 2012 year classes were 0.9%, 0.4% and 6.3% respectively. On average, F1 ELT were approximately 40 cm in total length and weighed 1500 g by the time they reached 1 year of age. Successful artificial induction of spawning was achieved in 1‐year‐old F1 ELT using a gonadotropin‐releasing hormone analogue (GnRHa). Induction of spawning was successful at the first administration of GnRHa in the 2010, 2011 and 2012 year classes. First spawning was observed at 4 or 5 days post implantation, which indicated that oogenesis and spermatogenesis progressed within 1 year of rearing in land‐based tanks. During spawning periods, the average number of fertilized eggs and the average number of hatched larvae per spawning event in the 2010, 2011 and 2012 year classes were 20,480 eggs day^?1 and 177 larvae day^?1, 39,423 eggs day^?1 and 9347 larvae day^?1, and 819,555 eggs day^?1 and 674,445 larvae day^?1 respectively. Therefore, it was concluded that both male and female ELT reared in land‐based tanks were capable of reproduction at 1 year of age.  相似文献   

Transcriptome-based approaches for clarification of nutritional responses and improvement of crop production     

Hinako Takehisa  Yutaka Sato 《Breeding Science》2021,71(1):76

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Effect of pineapple stem starch feeding on rumen microbial fermentation,blood lipid profile,and growth performance of fattening cattle     

Anchalee Khongpradit  Phoompong Boonsaen  Nitipong Homwong  Yutaka Suzuki  Satoshi Koike  Suriya Sawanon  Yasuo Kobayashi 《Animal Science Journal》2020,91(1)

Pineapple stem starch (PS) was evaluated for its suitability as a new starch source in concentrate for fattening cattle, based on the growth performance, blood profile, and rumen parameters of 36 steers in a 206‐day feeding study. PS was formulated as a 40% concentrate and fed with forage in comparison with ground corn (GC) and ground cassava (CA) formulated at the same level. PS feeding improved weight gain and feed conversion ratio without affecting feed intake. PS did not obviously influence blood lipid profiles throughout the experiment. Ruminal concentration of total short‐chain fatty acids (SCFA) increased with PS without affecting SCFA composition throughout the feeding study. Rumen amylolytic group, especially Ruminococcus bromii, was dominant in the rumen microbial community, and showed increased abundance by PS feeding throughout the experiment. These results clearly indicate the potential of PS as a useful starch source for fattening cattle in terms of rumen fermentation and growth performance.  相似文献   

The effect of slag on paddy rice     

Michio Ota  Hitoshi Kobayashi  Yutaka Kawaguchi 《Soil Science and Plant Nutrition》2013,59(1):45-46

To raise more rice in Japan we have placed much fertilizers in the fields, thus the soils often have been degraded by the leaching of essential elements including Fe to such a extent as rice roots are injured by the H₂S produced by the reduction of sulphates. It has been encouraged by law to place non-sulphate fertilizers and iron compounds in these fields.  相似文献   

On the soil colour,determined by spectrophotometer     

Yutaka Kamoshita  Yutaka Yamada 《Soil Science and Plant Nutrition》2013,59(3):107-109

Results, here published, are from the determination of the colour, by the use of spectrophotometer (Shimazu, QR-50) with the soils from pedogenic horizons of principal soil types In Japan.  相似文献   

Genesis and characteristics of brown forest soils derived from Serpentine in Kyushu,Japan     

Ichiro Kanno  Yutaka Onikura  Shizuoki Arimura  Shoichi Tokudome 《Soil Science and Plant Nutrition》2013,59(3):6-15

One of the main objects of the present study is to determine what genetic soil types have been formed from ultra-basic rocks such as serpentine under humid, subtropical conditions. Red-Yellow soils, which are important zonal soils in Kyushu, have not been formed from serpentine, but Brown Forest soils have been formed, as will be described in the part 2 of this paper. This fact for the most part has been governed by the mineralogical and chemical peculiarities of serpentine. Therefore the part 1 of this paper deals with the mineralogical and chemical characteristics of serpentine as a parent rock from which Brown Forest soils have developed.  相似文献   

Quantitative evaluation of the degree of sprout leaf bending of rice cultivars using P-type Fourier descriptors and principal component analysis   总被引：1，自引：0，他引：1  

Zeyu Zheng  Hiroyoshi Iwata  Yutaka Hirata  Yoshiyasu Tamura 《Euphytica》2008,163(2):259-266

For decades, seedling peaches have been used as the standard rootstock in California almond orchards. Vigorous, deep rooted trees are needed in almond orchards for maximum yields and to withstand the annual tree-shaking at harvest. Currently, researchers are actively evaluating rootstocks for almonds in field trials and in various screening protocols. In this study, seedling rootstocks, obtained from male-sterile advanced generation peach-almond (PEAL) hybrid mother trees, were compared with ‘Nemaguard’ peach seedlings for emergence in the nursery row, trunk caliper at propagation time, and end of season dormant above ground tree weight. Seedling emergence was affected significantly (P ≤ 0.05) by seed source, as was trunk caliper and end of season dormant above ground tree weight. Trunk caliper and dormant above ground tree weight were also affected significantly (P ≤ 0.05) by planting year. Results obtained in this study demonstrate the enhanced first year growth from seedlings of advanced generation PEAL hybrids, as compared to ‘Nemaguard’ seedlings. Seedling emergence in the rootstock bed was not affected significantly by planting year. Advanced generation PEAL hybrid seedlings were ready for June-budding at an earlier date compared to ‘Nemaguard’ seedlings, providing the potential for larger-sized finished nursery stock by the end of the growing season. Due to the male-sterile status of the advanced generation PEAL mother trees, bloom periods of several root-knot nematode resistant rootstock cultivars were examined for their degree of synchronicity with the mother trees. The examined rootstocks and mother trees varied in both chill hour and post-chill heat requirements necessary to effect bloom. ‘Flordaguard’ peach rootstock began bloom in advance of the male-sterile mother trees, whereas the bloom period of ‘Tsukuba No. 4’ occurred well after, suggesting they would not be effective synchronous pollenizers for consistent hybrid seed production. Based on more limited flowering period data, better bloom synchronicity was achieved with a Tsukuba No. 4 X Flordaguard hybrid.  相似文献   

A dual-spectral camera system for paddy rice seedling row detection   总被引：2，自引：0，他引：2  

Yutaka Kaizu  Kenji Imou 《Computers and Electronics in Agriculture》2008,63(1):49-robotics

A new method is presented for detecting rows of rice seedlings to facilitate the navigation of rice transplanters. Generally, an independent NIR or RGB camera is used as a vision sensor for agricultural vehicles; however, strong reflections on the water surface make row detection more difficult in flooded paddy fields compared to dry fields. To solve this problem, we developed a dual-spectral camera system that consists of a pair of low-cost monochrome cameras with optical filters. Different wavelength images of the same location can be taken simultaneously in real-time. An experiment conducted under cloudy conditions showed that this system could reduce water surface noise and clearly detect seedling rows.  相似文献   

Karyotype analysis of interspecific fusants of basidiomycetes by pulsed-field gel electrophoresis     

Takeshi Yokono  Yutaka Tamai  Tomonori Azuma  Yoh Sakuma  Kiyoshi Miura  Yasuo Kojima  Masahide Sunagawa  Masatake Ohmasa 《Journal of Wood Science》2000,46(6):480-484

The purpose of this research was to analyze the karyotype of the interspecific fusants of twoPleurotus species. Auxotrophic mutants derived from the cultivated strain ofP. ostreatus andP. cornucopiae were used. Protoplasts were fused electrically, and the fusants were selected under auxotrophic complementation. Esterase isozyme analysis showed that several fusants had isozyme bands originating from both parental strains, and others had unilateral isozyme bands. The fusant that had expressed isozyme bands of both parental strains showed chromosomal DNA bands of both of the parental strains in pulsedfield gel electrophoresis analysis. Despite the above results, the chromosomal composition of the fusants obtained by the pulsed-field gel electrophoresis did not exhibit all of the bands of both fusion parents.  相似文献   

Analysis of the electrophoretic karyotype ofFlammulina velutipes     

Doolyi Kim  Yutaka Tamai  Tomonori Azuma  Akira Harada  Akira Ando  Yoh Sakuma  Kiyoshi Miura 《Journal of Wood Science》2000,46(6):466-469

The karyotype ofFlammulina velutipes (Curt.: Fr.) Sing. was analyzed electrophoretically using contourclamped homogeneous electric field gel electrophoresis and hybridization with DNA probes. The chromosomal DNA from the monokaryon (Fv-4K) and the dikaryon (Fv-4) were resolved into six and eight bands, respectively. The sizes of the chromosomes ranged from 1.9 to 6.0 megabase (Mb) pairs. Each of the separated bands of chromosomal DNA was identified by use of five cloned probes. The number of these chromosomes was estimated to be 6 and 12, respectively; and the size of the entire genome was estimated to be about 20.1 and 38.6Mb, respectively. From a comparison of the hybridization patterns, the existence of allelic chromosomes of different sizes was deduced in the Fv-4 strain.  相似文献