Nitrogen-fixing microorganisms in paddy soils XIV     

Tadashi Katayama  Michiharu Kobayashi  Azuma Okuda 《Soil Science and Plant Nutrition》2013,59(2):32-37

In the preceeding paper (1), it was reported that when R. capsulatus is mixed with B. subtilis, in spite of no nitrogen fixation in separate cultures, by using a glycerol or starch medium, the combination was able to fix molecular nitrogen and it seems that there is a correlation between the production of pyruvic acid and the nitrogen fixation in the mixed culture.  相似文献   

Systems for making NIAS Core Collections, single-seed-derived germplasm, and plant photo images available to the research community     

Masaru Takeya  Fukuhiro Yamasaki  Sachiko Hattori  Akito Kaga  Norihiko Tomooka 《Genetic Resources and Crop Evolution》2013,60(7):1945-1951

The National Institute of Agrobiological Sciences (NIAS) Genebank coordinates the conservation of plant, microorganism, and animal genetic resources related to food and agriculture in Japan. It also coordinates the distribution of genetic resources in the public domain for research, breeding, and educational purposes. To operate the NIAS Genebank efficiently, we have developed a genetic resources database, data management software, and web-based data retrieval systems to make the data available worldwide. This article describes the NIAS Genebank’s Core Collections of global and Japanese soybean (Glycine max (L.) Merr.), Japanese azuki bean (Vigna angularis (Willd.) Ohwi et Ohashi), and Japanese wheat (Triticum aestivum L. s. l.), all of which are available through the Genebank website. This article also describes new features of the NIAS Genebank database, such as the ability to select single-seed-derived germplasm of soybean in the plant search system and to download photographic data on accessions. By using the downloaded plant image PDF files, users can obtain detailed passport and agronomic information by clicking on the image of an accession of interest.  相似文献   

Nitrogen-fixing microorganisms in paddy soils (Part 1) Characteristics of the nitrogen fixation in paddy soils     

Azuma Okuda  Masuro Yamaguchi 《Soil Science and Plant Nutrition》2013,59(1):102-104

In most paddy soils, as is already well-known, the crop yield goes on decreasing just for the first few years and then stabilizes at a comparatively high level with no supply of fertilizer or manure.  相似文献   

Nitrogen-fixing microorganisms in paddy soils (Part 2) distribution of blue-green algae in paddy soils and the relationship between the growth of them and soil properties     

Azuma Okuda  Masuro Yamaguchi 《Soil Science and Plant Nutrition》2013,59(1):4-7

As was shown in the previous report^l), a close connection between the photosynthetic autotrophs and nitrogen fixation in paddy soils was demonstrated.  相似文献   

Nitrogen-fixing microorganisms in paddy soils (Part 3) distribution of non-sulphur purple bacteria in paddy soils     

Azuma Okuda  Masuro Yamaguchi  Shuro Kamata 《Soil Science and Plant Nutrition》2013,59(1):131-133

The possible significance of blue-green algae in the nitrogen economy of paddy soil has been pointed out by many investigators.  相似文献   

Nitrogen-fixing microorganisms in paddy soils: VI     

Azuma Okuda  Masuro Yamaguchi 《Soil Science and Plant Nutrition》2013,59(2):76-85

During the experimental study of the role of blue-green algae in the nitrogen economy of paddy fields which were hitherto carried out in our laboratory, it was observed that small animals in paddy fields such as water fleas, mud snails, small freshwater fish, tadopoles or larvae of small insects had a preference for feeding on blue-green algae.  相似文献   

Stem productivity in relation to nitrogen concentration and carbon isotopic composition (δ13C) in leaves of hinoki cypress (Chamaecyparis obtusa Endlicher) plantations in Shikoku district,Japan     

Yoshiyuki Inagaki  Kazuki Miyamoto  Shiro Okuda  Mahoko Noguchi  Takeharu Itou  Kyotaro Noguchi 《Soil Science and Plant Nutrition》2013,59(5):710-718

The stem productivity of the hinoki cypress (Chamaecyparis obtusa Endlicher) in relation to plant nitrogen status and water-use efficiency was investigated in the Okuono (OKU) and Karakawa (KRK) areas in Shikoku district, Japan, where abundant precipitation occurs. The nitrogen concentration and carbon isotopic composition (δ¹³C) in the leaves were used as indexes of plant nitrogen status and water-use efficiency, respectively. The leaf nitrogen concentration increased with decreasing soil carbon/nitrogen (C/N) ratio and with increasing soil pH. There was a marginally significant negative correlation between leaf δ¹³C and soil water content in the KRK area, but leaf δ¹³C in the OKU area did not correlate with the soil water condition, and increased on the upper slope. The results suggest that hinoki trees in the KRK area have higher water-use efficiency (high leaf δ¹³C) under lower soil water conditions. In the OKU area, meanwhile, leaf δ¹³C in the upper slope was higher due to adaptation to adverse conditions. When 12 plots in two areas were included, the mean height and stem increments increased with increasing leaf nitrogen concentration and with decreasing leaf δ¹³C. These findings suggest that nitrogen acquisition is a primary factor for stem productivity in the areas concerned but the productivity of some forests is restricted by the soil water condition or other conditions, as indicated by the high value of leaf δ¹³C. The measurement of nitrogen concentration and δ¹³C in leaves can provide us with valuable insights into the relative importance of nitrogen, water and other conditions on stem productivity in the two areas.  相似文献   

Comparative studies of the changes in enzymatic activities in hardy and less hardy cultivars of winter wheat in late fall and in winter under snow     

Shonosuke Sagisaka  Yusuke Matsuda  Tohru Okuda  Sachio Ozeki 《Soil Science and Plant Nutrition》2013,59(3):543-550

Abstract

The synthetic activity of protein and changes in the activity profiles of enzymes during cold acclimation were studied in leaves, stems, and crowns of a hardy winter wheat cultivar ( Triticum aestivum L. cv. Horoshirikomugi) and a less hardy winter wheat cultivar (Triticum aestivum L. cv. Norin 61). The results showed that one of the genetic differences between the two cuitivars is found in the activities of protein synthesis under low temperatures. The profiles of the changes in enzymatic activities showed that the adjustment of enzymatic activities was a tissue-specific event to accommodate environmental changes. The synthesis of the enzymes involved in a peroxide scavenging system such as hexokinase, glucose-6-phosphate dehydrogenase, dehydroascorbate reductase, ascorbate peroxidase, and so on started at the acclimation stage, while the phosphoglucose isomerase, which appears to be a maintenance-type enzyme in the wintering wheat, showed a small increase in the activity at later stages of acclimation period in their stems of both cuitivars. When the field was covered with snow, the catalase activity in the leaves started to decrease abruptly, while catalase activities in the stems and crowns did not exhibit appreciable changes during the life under snow. The life-cycle dependent changes in enzymatic activities appear to occur in late March or early April under snow.  相似文献   

New analogs of pochonicine,a potent β-N-acetylglucosaminidase inhibitor from fungus Pochonia suchlasporia var. suchlasporia TAMA 87     

Yuhichi Mushiake  Aya Tsuchida  Asami Yamada  Hiroshi Kanzaki  Toru Okuda  Teruhiko Nitoda 《Journal of Pesticide Science》2021,46(1):115

Three novel analogs of pochonicine (1) were isolated from a solid fermentation culture of the fungal strain Pochonia suchlasporia var. suchlasporia TAMA 87, and their structures were elucidated as 7-deoxypochonicine (2), 6-deoxypochonicine (3), and 6,7-dideoxypochonicine (4). These analogs were found to possess the same stereochemistry as pochonicine. Comparison of β-N-acetylglucosaminidase (GlcNAcase) inhibitory activity between these analogs and pochonicine suggested that the C-6 hydroxy group of pochonicine was essential to its potent GlcNAcase inhibitory activity and that the C-7 hydroxy group also contributed to the activity, but to a lesser extent than the C-6 hydroxy group.  相似文献   

Ecological functions of persistent Japanese cedar litter in structuring stream macroinvertebrate assemblages     

Masaru Sakai  Yosihiro Natuhara  Keitaro Fukushima  Ayumi Imanishi  Kensuke Imai  Makoto Kato 《Journal of Forest Research》2013,18(2):190-199

Stream macroinvertebrate assemblages are expected to be affected by the abundance and constitution of litter from surrounding forests. We compared forest floor cover, overland flow, stream environment, and stream macroinvertebrate assemblages between the catchments of a Japanese cedar plantation (CP) and a primary deciduous forest (DF). Both systems experience excessive deer browsing. Understory vegetation cover was higher in the DF than in the CP in summer, although cover was low (<20 %), possibly because of excessive deer browsing. Litter cover was much higher in the CP than in the DF in summer as a result of the long abscission period, slow breakdown, and low rate of dispersal of Japanese cedar litter compared to deciduous litter. Monthly overland flow was always lower in the CP than in the DF, and substrate size was smaller in the DF stream. In the CP, cedar litter accumulated in the stream, probably because of its low breakdown rate and morphology, and abundant shredder taxa characterized the macroinvertebrate assemblage. In contrast, abundant burrower taxa characterized the macroinvertebrate assemblage in the DF stream. These results imply that Japanese cedar litter functions in structuring the macroinvertebrate assemblage by supplying persistent food resources for detritivores, and by buffering fine sedimentation via overland flow under excessive deer browsing.  相似文献