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51.
Indian dwarf wheat (Triticum aestivum L. ssp. sphaerococcum (Perc.) Mac Key, synonym: T. sphaerococcum Perc.) is endemic to southern Pakistan and northwestern India. It was one of the main winter crops grown by ancient Indian cultures. However, it disappeared from the record during the early twentieth century, especially after the Green Revolution brought modern wheat varieties into India and Pakistan. Whether or not Indian dwarf wheat is presently cultivated has been unclear. Here we report on the rediscovery of the cultivation of this wheat in northern Karnataka and southern Maharashtra in India. Molecular genetic analysis of the chloroplast DNA of the two specimens collected at location 3 revealed that both samples have a unique haplotype that is specific to Indian dwarf wheat. We found this wheat at three locations in 2010, but at only one of the three locations in 2011. Therefore, the future survival of this subspecies is uncertain. Further ethnobotanical research is urgently needed to conserve this unique genetic resource for the future.  相似文献   
52.
The presence of aluminum oxyhydroxide and its micromorphological characteristics in sclerotium grains were examined by SEM, TEM, and EDX analyses. A spherical fraction with a diameter of 100 nm, which contained C and Al as the predominant elements, was recognized as the unit particle of the matrix of sclerotium grains. The Al polymorphs and the Si spherical structures found in the ignited grains were assumed to correspond to boehmite and opaline silica particles, respectively. SEMI analysis revealed the presence of a needle ball structure inside the hollow part of sclerotium grains. The relationship between the inner structure of sclerotium and biochemical processes of the host fungi was discussed.  相似文献   
53.
Samples described in the previous paper were analyzed for humus composition by the method of Kumada el al,, elementary composition of humic acids, nitrogen distribution among humic acid, fulvic acid, and humin, and organic matter composition by the modified Waksman method. The samples obtained by physical fractionation from each horizon of Higashiyama soil were as follows: f1 and f2 from the L layer, f1, f2 and f3 from the F layer, f1 f2, sand, silt, and clay fractions from the H-A and A horizons.

With the progress of decomposition, the following tendencies were rather clearly observed.

The extraction ratio of soluble humus, amounts of humic acid and fulvic acid, and PQ, value tended to increase with some exceptions. The degree of humification of humic acid proceeded. Most humic acids belonged to the Rp type, but those of the clay fractions belonged to the B type.

As for the elementary composition of humic acid, transitional changes from the Lf1 to the clay fraction of the A horizon were observed. But differences in elementary composition among humic acids were far less, compared with those among whole fractions.

Nitrogen contents in humic, fulvic, and humin fractions increased with the progress of decomposition and humiliation, and the largest relative increase was found in fulvic acid nitrogen.

According to the modified Waksman's method, the amounts of residues and protein increased, while the total amounts of each extract, except for the HCl extract, and the amounts of sugars and starch, phenolic substances, hemicelluloses and pectin, and cellulose decreased. Sugars and starch comprised only a small portion of the hot water extract, and polyphenols substances comparable to sugars and starch were also found in the extract. Hemicelluloses and pectin accounted for only about one-half of the HCl extract. Several characteristic differences in the elementary composition of extracts and residues were found.

Pheopigments existed in benzene-ethanol extracts and their amounts seemed to decrease from Lf1 to Ff2.  相似文献   
54.
The results of elementary analysis of each fraction separated physically from each horizon of five forest soils were described.

The biggest fraction was Lf2 (fresh litter) in L layers, Ff2 (>2 mm) or Ff2 (2-1 mm) is F layers and Hf4 in H layers.

Of all the changes in various parameters which accompanied decomposition and humification, the change in C/N ratio was the most obvious; the C/N ratio for plant remains easily decreased to 25 or 30 during decomposition, but any further decrease in this value occurred with difficulty. It was specifically pointed out that Hf7 and Hf2 were fairly different materials from the other fractions.

As for A horizons, both carbon and nitrogen contents increased, and CIN ratios decreased in the order of sand, silt and clay fractions.  相似文献   
55.
It is well known that when inorganic elements such as boron (B), calcium, cobalt, and manganese are added to media in combination or alone, they stimulate the germination and/or tube growth of various kinds of pollen (Schmücker 1933; Loo and Hwang 1944; Yamada 1958; Brewbaker and Kwack 1963). Among these elements, the stimulatory effect ofB is the most effective and generally recognized. Aluminum (Al) belongs along with B to Group IIIa in the periodic table, and Fähnrich and Ultlich (1964) reported that Al inhibited the germination and growth of the pollen tube of Petunia hybrida and Antirrhinum majus. However, stimulatory effects of Al on pollen germination or pollen tube growth had not been previously reported.  相似文献   
56.
In an etiological study to identify the causal agent of red stripe of rice, white bacterial colonies were consistently isolated from all diseased leaf samples collected in Indonesia. All the bacterial isolates were pathogenic to rice and caused symptoms similar to red stripe. The bacterial infection in rice leaves was confirmed histologically. Bacterial masses were observed in the lumina of xylem vessels in the lesion area, especially in those of connecting strands. Analysis of the 16S rDNA of the causal bacterium gave best matches to the 16S rDNA sequence of Microbacterium spp. of Microbacteriaceae which includes Clavibacter. Received 9 September 1999/ Accepted in revised form 16 November 1999  相似文献   
57.
On Shimokamagari, an island of the Seto Island Sea, patterns of vegetation in the landscape were studied using vegetation maps. Relationships between social and economic changes, site conditions and the vegetation were examined from a historical perspective. In the process of economic development, mandarin orange production became important on this island. However, over-production, a reduction in the price of mandarin oranges and low-temperature damage to orange trees caused large citrus orchards to be abandoned. A plant community dominated by kudzu appeared in the abandoned orchards and the pine forests, as well. These changes in orchards were connected with the natural site conditions, such as soil, geology, inclination, elevation, direction of slope, and also with artificial conditions, such as density of working paths. Another factor causing change was the replacement of the organic fertilizer of litter from forests by chemical fertilizer since the 1960's. As a result, medium and small forests of pine became tall forests and tall forests of pine changed into tall oak forests. In the human-dominated areas, the major factors affecting the process of vegetation were economic activities, and after the abandonment of the farm-lands, forest succession were controlled by natural site conditions. This paper was presented at the World-Congress of Landscape Ecology in Ottawa, 1991 Titles are tentative translations for original titles in Japanese by the authors.  相似文献   
58.
A serological survey was conducted on 4,080 swine sera collected for the years 1985-90. The swine sera positive to A/New Jersey/8/76 (swine type H1N1) strain were observed in annual (10-20%) and monthly (20-40%) incidences during the observation period except for occasional months. Antibodies to recent human H1N1 viruses in swine were recognized in relation to the human H1N1 influenza epidemics. Antibody responses of swine to human H3N2 strains appeared irrespective of human epidemics with the virus in the years 1985-87. However, in 1988 almost no antibodies to three human H3N2 isolates of 1983-88 were observed for this year except a few months though the human epidemic occurred in the area. Although in 1989-90 many swine had antibodies to the three strains in the percentage of 3 to 35, no antibody to the latest isolate, A/Hokkaido/20/89 (H3N2), was found for almost all the months of both years. These findings differed markedly from the possible relationship between the prevalence of H3N2 virus-antibodies in swine and the human influenza epidemics, which were described previously in many reports including our studies.  相似文献   
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