Photoperiodic reaction of sexual and asexual reproduction in Fragaria chiloensis L. CHI-24-1 plants grown at various temperatures     

Tomohiro Yanagi  Takanori YachiNcbuyuki Okuda 《Scientia Horticulturae》2006

Floral initiation of a wild strawberry strain, Fragaria chiloensis CHI-24-1, is strongly induced by a 24 h day-length (DL) treatment for 40 days consisting of natural daylight and continuous lighting at night by an incandescent lamp. To use the characteristics of floral initiation in CHI-24-1 as a genetic resource for breeding of cultivated strawberries, the photoperiodic reactions of sexual and asexual reproductive growth under various temperature conditions should be clarified. For that purpose, we examined: (1) floral initiation, inflorescence emergence and runner production seasons of CHI-24-1 plants grown under natural climatic conditions in an open field at the Faculty of Agriculture, Kagawa University and (2) the effects of various DLs and temperatures on floral initiation and runner production of CHI-24-1 plants. When the CHI-24-1 plants were grown under natural conditions, the floral initiation, inflorescence emergence and runner production were observed, respectively, in late autumn, spring, and from spring to autumn. Floral initiation of CHI-24-1 plants was induced strongly by 24 h DL at mean temperatures greater than 20 °C. The maximum floral initiation rates were 90% in the parent plant and 94% in the daughter plants, which were linked by runners to the parent plant. The floral initiation of the daughter plants occurred under 20, 22, and 23 h DL at mean temperatures greater than 20 °C, but not for the parent plants. Floral initiation was induced in 100% of the parent plants by the 8 h DL and the lowest mean-temperature conditions. Results of those experiments indicated that CHI-24-1 was an absolute long day plant having critical DL of about 20 h at mean temperatures greater than 20 °C, even though it was a June-bearing strawberry plant. In addition, CHI-24-1 was a facultative short-day plant at mean temperatures of less than 15 °C.  相似文献   

Primary taste center in the goatfish of genus Parupeneus     

Masato Kirino  Takanori Ikenaga  Junzo Tsukahara  Charles Flamb  Sadao Kiyohara 《Fisheries Science》2006,72(3):461-468

ABSTRACT:   This study was carried out to obtain fundamental information on the morphology of the primary taste center in the goatfish of genus Parupeneus. The primary taste center includes a dorsal facial lobe (dFL), ventral facial lobe (vFL) and vagal lobe (VL). The dFL is extraordinarily developed rostrocaudally to occupy the dorsal surface of the medulla. The vFL extends as a longitudinal column between the dFL and VL, and its rostral end connects to the proximal portion of the dFL at the level of most anterior medulla. The VL appears slightly caudal to the rostral end of vFL as a longitudinal column and reaches more caudally than the facial lobe (FL). The dFL includes tubercular and laminated structures. Each tubercle consists of four layers: a marginal layer, a superficial molecular layer, a cell-cluster layer and a deep layer. Sublaminar organization was also found in the cell-cluster layer. No laminar organization was found in either the vFL or VL but distinct clusters of small cells were frequently seen throughout both the lobes. Tracing experiments with the carbocyanine dye diI show that the facial fibers end in the entire dFL and vFL and the anterior portion of the intermediate nucleus of the facial lobe (NIF), while glossopharyngeal fibers terminate in the dorsolateral portion of the anterior VL and the intermediate portion of NIF. Trigeminal fibers project only to the most lateral aspects of the anterior vFL in addition to normal targets such as spinal trigeminal and medial funicular nuclei.  相似文献   

Bacterial Communities Responsible for the Decomposition of Rice Straw Compost in a Japanese Rice Paddy Field Estimated by DGGE Analysis of Amplified 16S rDNA and 16S rRNA Fragments   总被引：4，自引：0，他引：4  

Takanori Tanahashi  Jun Murase  Kazuo Matsuya  Motoki Hayashi  Makoto Kimura  Susumu Asakawa 《Soil Science and Plant Nutrition》2005,51(3):351-360

To estimate the succession and phylogenetic composition of the bacterial communities responsible for the decomposition of rice straw compost under flooded conditions during the cultivation period of paddy rice, denaturing gradient gel electrophoresis (DGGE) analyses targeting 16S rDNA and 16S rRNA, followed by sequencing were conducted in a Japanese paddy field. The DGGE bands of the bacterial communities in the rice straw compost were significantly more numerous in the DNA samples than in the RNA samples. Although the band number of the DNA samples was almost constant throughout the period, RNA samples showed fewer DGGE bands after mid-season drainage than before it. Thus, about 81% of the bacteria present in rice straw compost were considered to be metabolically "active" before mid-season drainage and about 62% after it. The changes in the DGGE patterns of bacterial DNA and RNA before and after mid-season drainage, respectively, were also revealed by cluster analysis and principal component analysis of the DGGE patterns. These results indicated that the bacterial communities of rice straw compost incorporated into flooded paddy fields changed gradually along with the decomposition, except for the period of mid-season drainage, but that they were influenced by mid-season drainage. Members of β-, γ- and δ-Proteobacteria, Cytophaga-Flavobacterium-Bacteroides (CFB) group, Chlorobia, Verrucomicrobia, Chloroflexi, Spirochaetes, Firmicutes (clostridia) and Actinobacteria were present during the decomposition of rice straw compost. Characteristic "active" bacteria among them were as follows: Clostridium, Acinetobacter (γ-Proteobacteria) and β-Proteobacteria before mid-season drainage, Flavobacterium, Chondromyces , Chlorflexi and δ-Proteobacteria after mid-season drainage, and Spirochaeta and myxobacteria throughout the period.  相似文献   

The pollutant loads from a paddy field watershed due to agricultural activity     

Hyungjun Lee  Takanori Masuda  Hiroshi Yasuda  Yoshihiko Hosoi 《Paddy and Water Environment》2014,12(4):439-448

Observations were performed in a small agricultural watershed for four consecutive irrigation periods in order to characterize fluctuations in the characteristics of pollutant runoff from paddy fields. During the puddling and rice-planting period and at the beginning of the mid-summer drainage period, both the pollutant concentrations and pollutant loadings of suspended solids, total nitrogen, and total phosphorus increased. In contrast, the pollutant net loading of total nitrogen was negative during the intermittent irrigation period. These results indicate that changes in the specific agricultural activities in the paddy fields cause temporal fluctuations of the pollutant runoff. Previous studies which focused on paddy fields have dealt with unit loading for entire irrigation period only. However, the unit loading for the entire irrigation period cannot take into account pollutant loading fluctuations due to differences in agricultural activity. Thus the unit loading of pollutant should be evaluated for each agricultural activity during the irrigation period.  相似文献   

Microsatellite variability within and among local landrace populations of tea, Camellia sinensis (L.) O. Kuntze, in Kyoto, Japan     

Takanori Ohsako  Takafumi Ohgushi  Hino Motosugi  Kouzou Oka 《Genetic Resources and Crop Evolution》2008,55(7):1047-1053

Genetic variability within and among eight landrace populations of tea (Camellia sinensis (L.) O. Kuntze) located in southern Kyoto, Japan, was surveyed with six microsatellite markers. The average number of alleles per locus was 3.83 to 4.67 for landrace populations, whereas the corresponding value among modern cultivars and breeding lines was 6.63. Expected heterozygosity values averaged over loci within landrace populations ranged from 0.498 to 0.723. A similar level of variation, 0.682, was observed for cultivars and breeding lines. High fixation index values (0.177–0.417) for each population are consistent with biparental inbreeding within the population. Genetic differentiation among local populations was extremely low with F _ST = 0.062, although AMOVA revealed significant differentiation among landrace populations. We propose that these populations share a common ancestral gene pool and that some degree of artificial selection within each population has been performed by local farmers. Neighbor-joining analysis revealed that genetic relationships among populations reflect geographical location of populations. This might result from more frequent genetic exchange by nearby farmers.  相似文献   

Antioxidant and antiulcerative properties of phenolics from Chinese quince, quince, and apple fruits     

Hamauzu Y  Inno T  Kume C  Irie M  Hiramatsu K 《Journal of agricultural and food chemistry》2006,54(3):765-772

To evaluate the health benefits of Chinese quince and quince phenolics, their antioxidant properties and antiulcerative activity were investigated in comparison with apple phenolics as a reference. The strength of antioxidant activity and DPPH radical scavenging activity of these fruit phenolics varied according to different in vitro evaluation systems, whereas the antioxidative property of rat blood increased in all rats orally administered phenolics. Ferulic acid and isoferulic acid were detected as major metabolites in rats given apple phenolics, quince phenolics, and 5-caffeoylquinic acid standard. (-)-Epicatechin and its 3'-O-methyl ether could be detected in rats administered apple phenolics and (-)-epicatechin standard. In the ethanol-induced gastric ulcer, pre-administration of Chinese quince and quince phenolics suppressed the occurrence of gastric lesions in rats, whereas apple phenolics seemed to promote ulceration. The trend of myeloperoxidase activity was similar to that of the ulcer index. The results showed that Chinese quince and quince phenolics might have health benefits by acting both in blood vessels and on the gastrointestinal tract.  相似文献   

Physiological and transcriptomic analysis of responses to different levels of iron excess stress in various rice tissues     

May Sann Aung  Hiroshi Masuda  Takanori Kobayashi 《Soil Science and Plant Nutrition》2018,64(3):370-385

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Loss of p16/Ink4a drives high frequency of rhabdomyosarcoma in a rat model of Duchenne muscular dystrophy     

Naomi TERAMOTO  Masanari IKEDA  Hidetoshi SUGIHARA  Takanori SHIGA  Takashi MATSUWAKI  Masugi NISHIHARA  Kazuyuki UCHIDA  Keitaro YAMANOUCHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(9):1416

Rhabdomyosarcoma (RMS) is an aggressive type of soft tissue sarcoma, and pleomorphic RMS is a rare subtype of RMS found in adult. p16 is a tumor suppressor which inhibits cell cycle. In human RMS, p16 gene is frequently deleted, but p16-null mice do not develop RMS. We reported that genetic ablation of p16 by the crossbreeding of p16 knock-out rats (p16-KO rats) improved the dystrophic phenotype of a rat model of Duchenne muscular dystrophy (Dmd-KO rats). However, p16/Dmd double knock-out rats (dKO rats) unexpectedly developed sarcoma. In the present study, we raised p16-KO, Dmd-KO, and dKO rats until 11 months of age. Twelve out of 22 dKO rats developed pleomorphic RMS after 9 months of age, while none of p16-KO rats and Dmd-KO rats developed tumor. The neoplasms were connected to skeletal muscle tissue with indistinct borders and characterized by diffuse proliferation of pleomorphic cells which had eosinophilic cytoplasm and atypical nuclei with anisokaryosis. For almost all cases, the tumor cells immunohistochemically expressed myogenic markers including desmin, MyoD, and myogenin. The single cell cloning from tumor primary cells gained 20 individual Pax7-negative MyoD-positive RMS cell clones. Our results demonstrated that double knock-out of p16 and dystrophin in rats leads to the development of pleomorphic RMS, providing an animal model that may be useful to study the developmental mechanism of pleomorphic RMS.  相似文献