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排序方式: 共有312条查询结果,搜索用时 15 毫秒
41.
Hideaki Saeki Masao Okamoto Junzo Azuma Hirofumi Inoue Masahiro Takiuchi Hiroshi Tarumi 《Soil Science and Plant Nutrition》2013,59(1):16-22
Basic information on the nature of soils, their potentialities, and their limitations is necessary to evaluate Cambodian agriculture properly, and to develop a program for increasing food and other crops. Suitable information has, however, been limited, especially as there is not to be found in any report much data relating to soils of different origins over the whole country. There is, needless to say, some information on confined areas of Cambodia. 相似文献
42.
In 1949, GEST and KAMEN (1,2) reported that Photosynthetic bacteria can fix molecular nitrogen. LINDSTROM et al. (3,4) tested the nitrogen fixing ability of five species of photosynthetic bacteria under the following four conditions; 1) anaerobic light, 2) aerobic light, 3) aerobic dark, 4) anaerobic dark. As the result of the experiment, they certified that it Was only under the anaerobic light condition that the bacteria can fix molecular nitrogen. 相似文献
43.
In the last report1) the purity of radioactive potassium. which had been produced by 41K (d, p) 42K nuclear reaction and separated from, radioactive anions by the use of ion exchange resin, was tested by means of its decay curve. By this test, it is difficult to distinguish 42K from 24Na contamination, because the half life of radioactive sodium (24Na) is 15.06 hours2) and it is very similar to that of radioactive potassium (42K) which is 12.4 hours. When the nuclear reaction 23Na (d, p) 24Na occurs, the cross section of this reaction for deuterons is about 100 times that of potassium nuclear reaction. In this case the purity of radioactive potassium (42K) could be confirmed by its Gamma-ray spectrum. According to the result, radioactive potassium of high purity was obtained. Potassium phosphate which was double-labeled by this radioactive potassium and imported radioactive phosphorus (32P) was applied to leaves or roots of bean plants. 相似文献
44.
Active surface agents are often added to spray solutions to facilitate the uniform wetting and coveringg of the leaf surfaces1),2). Some have reported that the addition of active surface agents increased the absorption of nutrients, but others have reported different results. 相似文献
45.
In the preceding paper (1), it was reported that even under aerobic shaking conditions, if R. capsulatus were mixed with Bacillus megaterium, the bacterial growth of both and nitrogen fixation were accelerated remarkably. 相似文献
46.
1. It was proved that under aerobic shaking conditions of the system of R. capsulatus mixed with Az. agilis or R. capsulatus mixed with B. megaterium, the bacterial growth of both and the nitrogen fixation were promoted markedly, comp:ired with the non-shaking culture. However, in the system of R. capsulatus mixed with B. subtilis under aerobic shaking conditions. such remarkable stimulative effects were not recognized altough some slow effects were recognized in the nonshaking culture. 2. It was also proved that under aerobic shaking conditions of the system of R. capsulatus mixed with Az. agilis or R. capsulatus mixed with B. megaterium the assimilative activity of carbon dioxide increased over 10 times more than in the separate pure culture. From these results, it is conceivable that a very good environment was created for the internal metabolism of R. capsulatus in such mixing systems (R-Az and R-Bm). 相似文献
47.
Changes in the metabolic pattern of proline-14C were examined in barley seedlings germinated at the low temperature of 2°C (LT) and compared with those germinated at 25°C (HT). In the LT shoots. proline-14C incorporation was higher in the cationic fraction and lower in the acid-neutral fraction than that of HT, respectively. More proline-14C of LT was converted to other amino acids, especially to acidic amino acids in free amino acid state, than was the HT proline-14C which had a comparatively wide distribution. In the LT protein fractions. more proline-14C was incorporated into the cytoplasmic protein than into the cell wall protein. On the contrary, the radioactivity of the lIT cell wall increased more distinctively. proline-14C in the two proteins of LT was a little less converted to other amino acids than in those of HT. A little higher radioactivity was found in the aspartate and glutamate of the LT protein hydrolysates. The hydroxyproline which is closely related with proline had a little lower level of radioactivity in the LT cell wall. 相似文献
48.
Matsuda Y Ikeda H Moriura N Tanaka N Shimizu K Oichi W Nonomura T Kakutani K Kusakari S Higashi K Toyoda H 《Phytopathology》2006,96(9):967-974
ABSTRACT In an attempt to physically protect greenhouse tomato plants from the powdery mildew fungus Oidium neolycopersici, we developed a new electrostatic spore precipitator in which a copper wire conductor is linked to an electrostatic generator and covered with a transparent acrylic cylinder (insulator). The conductor was negatively charged by the generator, and the electrostatic field created by the conductor was used to dielectrically polarize the insulator cylinder. The dielectrically polarized cylinder also produced an electrostatic force without a spark discharge. This force was directly proportional to the potential applied to the conductor and was used to attract conidia of the pathogen. The efficacy of this spore precipitator in protecting hydroponically cultured tomato plants from powdery mildew was evaluated in the greenhouse. The hydroponic culture troughs were covered with a cubic frame installed with the spore precipitator, and the disease progress on precipitator-guarded and unguarded seedlings was traced after the conidia were disseminated mechanically from inoculum on tomato plants. Seedlings in the guarded troughs remained uninfected during the entire experiment, in spite of rapid spread of the disease to all leaves of the unguarded seedlings. 相似文献
49.
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
50.
It is believed that some organic compounds form complexes with iron and aluminum and prevent the fixation of phosphate applied to soils. 相似文献