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151.
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
152.
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
153.
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
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
154.
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
155.
H. Murakami † S. Tsushima T. Akimoto K. Murakami I. Goto Y. Shishido 《Plant pathology》2000,49(5):584-589
Control of some soilborne pathogens may be achieved by use of decoy or catch crops. These stimulate the germination of resting spores, resulting in limited expression of disease symptoms. Results achieved using this approach are reported here using leafy daikon (radish, Raphanus sativus var. longipinnatus ) for control of Plasmodiophora brassicae , the cause of clubroot disease of Brassicaceae. Disease indices of Chinese cabbage plants grown in pots that had previously contained leafy daikon were lower compared with pots where no plants had been grown before (control pots). Numbers of resting spores of P. brassicae in soil in pots after cultivation with leafy daikon were reduced by 71% compared with control pots when resting spores were recovered and counted directly. In a field experiment, numbers of resting spores were reduced by 94% compared with the start of the experiment when leafy daikon was grown in advance of Chinese cabbage, but there was no reduction in disease severity in the Chinese cabbage. Plasmodiophora brassicae infected the root hairs of leafy daikon and those of Chinese cabbage, but no clubs were found on leafy daikon roots. The results from pot trials indicate that leafy daikon may be useful as a decoy crop for the control of clubroot disease in field crops. 相似文献
156.
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
157.
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
158.
Tsukamoto S Kuma A Murakami M Kishi C Yamamoto A Mizushima N 《Science (New York, N.Y.)》2008,321(5885):117-120
After fertilization, maternal proteins in oocytes are degraded and new proteins encoded by the zygotic genome are synthesized. We found that autophagy, a process for the degradation of cytoplasmic constituents in the lysosome, plays a critical role during this period. Autophagy was triggered by fertilization and up-regulated in early mouse embryos. Autophagy-defective oocytes derived from oocyte-specific Atg5 (autophagy-related 5) knockout mice failed to develop beyond the four- and eight-cell stages if they were fertilized by Atg5-null sperm, but could develop if they were fertilized by wild-type sperm. Protein synthesis rates were reduced in the autophagy-null embryos. Thus, autophagic degradation within early embryos is essential for preimplantation development in mammals. 相似文献
159.
Asep Ridwanudin Yutaka Haga Takayuki Katagiri Shuichi Satoh 《Aquaculture Research》2019,50(8):2218-2230
A feeding trial was conducted to evaluate the effect of nucleotides supplementation to low‐fish meal feed on growth and fatty acid composition of rainbow trout. Six isonitrogenous (42% crude protein) and isolipidic (18% crude lipid) diets were formulated containing fish meal and plant ingredients as main protein sources. The control diet was a basal diet without supplementation of nucleotides, and five experimental diets were prepared by supplementing one of the five different nucleotides in the form of 5′‐monophosphate (0.15%), that is inosine (IMP), adenosine (AMP), guanosine (GMP), uridine (UMP) and cytidine (CMP) onto basal diet. Two hundred forty juvenile rainbow trout with an initial average body weight 9.8 g were randomly distributed into twelve aquaria. After 15 weeks of feeding period, growth performance and feed utilization of rainbow trout were not significantly different among dietary treatments. Dietary GMP, UMP and CMP tended to accumulate crude lipid in the muscle and whole fish body. Moreover, dietary GMP, UMP and CMP significantly increased hepatic 18:3n‐3 and long‐chain homologue 18:4n‐3 and 20:4n‐3 contents. Hepatic 18:2n‐6 content showed also increase in fish fed GMP, UMP and CMP diets, but decreased in long‐chain homologue 20:3n‐6 and 20:4n‐6 contents. Decrease in 20:4n‐6, 20:5n‐3 and 22:6n‐3 contents was also found in the muscle of fish fed IMP, GMP and CMP diets. The present study clearly showed that there was no positive effect of dietary nucleotides on growth of fish, but dietary nucleotides particularly GMP, UMP and CMP altered polyunsaturated fatty acid composition of rainbow trout. 相似文献
160.
Ozaki K Nakahara Y Narama I 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(3):289-291
A dog presented with hematuria, and two small polypoid masses were detected in the urinary bladder. Histopathologically, the masses were located in the mucosal or submucosal layer. That tissue consisted of a random proliferation of spindle-shaped, round and pleomorphic cells with single or multiple large atypical nuclei and abundant cytoplasm, and eosinophil infiltration. These large cells were confirmed by immunohistochemical staining as fibroblasts, myofibroblasts and macrophages. Mitotic figure was rarely seen. These masses were diagnosed as eosinophilic polypoid cystitis with pseudosarcomatous proliferative tissue, since they consisted of a wide variety of cells and showed low growth activity. 相似文献