Submerged direct-seeded rice is more susceptible to lodging during the ripening period than is transplanted rice. Comparing different seeding methods of direct seeding cultivation, lodging resistance is considered to be highest in hill-seeded rice. However, practical hill-seeders did not exist, and previously direct-seeding had been conducted by broadcast- or row-seeding. This paper discusses the development of a hill seeder and improvements in the lodging resistance of hill-seeded rice, both of which have contributed to the recent widespread cultivation of submerged, direct-seeded rice in Japan. The newly developed hill-seeder effectively drives seeds intermittently into the puddled soil and enabled establishment of a hill which is composed of several plants as is a transplanted hill. Hill-seeded rice showed remarkable higher pushing resistance than broadcast-seeded rice across a range of seedling density and seeding depth after heading, while the plant length was longer in hill-seeded rice. It is suggested that the high lodging resistance of the hill-seeded rice is derived from the larger number of panicles per hill, because the lodging resistance varied depending on the number of panicles in a hill. The area cultivated by hill-seeding has been increasing since 1998, in 2004, it occupied 25% of the total submerged direct-seeded area.

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The glossy leaf is an important character related with disease and pest resistance as well as varietal differences in Brassica oleracea and Zea mays. The author aimed to clarify the characteristic of glossiness that was newly found in sorghum cultivars. The visual difference between glossy and non-glossy plants could be identified by whether or not sprayed water adheres to leaf blades. The phenotype of non-glossy plants whose leaves shed water was due to the high density of star-shaped waxes that were detected in the ultrastructural observations. Moreover, true-glossy plants which water adheres to the surfaces of all leaves from 1st to flag leaf stages were found among Indian indigenous cultivars. The visual character of true-glossy plants was due to a reduction in the number of star-shaped waxes on leaves from 1st to 5th leaf stages in the observation by scanning electron microscope (SEM).

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Recent progress in an understanding of the role of thyroid hormone (TH) on fish development was reviewed with particular reference to fish farming. TH is a small liposoluble hormone produced in thyroid follicles and has two bioactive forms, tetraiodothyronine (thyroxine, T₄) and triiodothyronine (T₃). Mother fish deposits a considerable amount of TH in developing oocytes. The amount of TH and ratio of T₃ to T₄ in eggs vary among species and stocks of the same species. The role of TH in eggs is not yet clear, though enhanced survival and growth of embryos and larvae by the enrichment of the eggs with TH have been reported in some cases. On the other hand, the role of TH that promotes larva-juvenile transition or metamorphosis has been established in teleost fish. The level of TH elevates at the onset of metamorphosis, and the treatment with TH can induce precocious metamorphosis. Considering the TH role in fish development, the disorder of its proper function could lead to deformity in juveniles, which is frequently observed in hatchery. In addition, many environmental chemicals have potential disrupting TH function in developing embryos and juveniles of fish.

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There are two growth types of plants for the number of developed leaves, heading time, and culm and panicle lengths within a population of a homozygous rice cultivar. However, this phenomenon has not been deeply investigated, because of lack of concrete data. Rice breeders and physiologists have paid little attention to it, regarding it as a genetically uncontrollable environmental variation. To study more details of the phenomenon, we grew two near-isogenic lines of rice with each one of the alleles for the Se1 locus conferring photoperiod sensitivity on chromosome 6 under natural long and short day-length conditions. In the line ER homozygous for the earliness allele Se1-e, and the line LR with the lateness allele Se1-u, N-leaf plants headed several days earlier than N+1-leaf plants. The N-leaf plants had shorter culms and longer panicles and were the upper-internode elongation type, whereas the N+1-leaf plants had opposite values of these characters. The proportion of these two kinds of plants changed in lines, plots and experiments. We discuss the meanings of this phenomenon from the viewpoints of rice cultivation to attain the uniform growth of plants, breeding to select individual plants with environmental variation, and fixation test to evaluate the uniformity needed as a cultivar.

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CCRF-CEM and Jurkat E6-1, human T cell leukemia, produced interleukin (IL)-2 stimulated with phorbol myristate acetate (PMA) and pokeweed mitogen (PWM). IL-2 cytokine production and mRNA expression of CCRF-CEM were increased by treatment with kaempferol, a tea (Camellia sinensis L.) flavonol, while those of Jurkat E6-1 were decreased by kaempferol treatment. We therefore investigated the nuclear factor expression of activated T cell (NFAT), a critical regulator of IL-2 gene transcription during T cell activation. In CCRF-CEM, NFAT induction of cytoplasmic extract and NFAT translocation to the nucleus were increased by kaempferol, demonstrating that kaempferol might affect the upstream cascade of T cell signaling. However, in Jurkat E6-1, NFAT induction of cytoplasmic extract was normal, but NFAT translocation to the nucleus was decreased by kaempferol treatment. In this report, it is demonstrated that kaempferol has different effects in the T cell signaling cascade.

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This paper focuses upon the incompatibility between poverty alleviation and environmental conservation and the solution to the incompatibility in an agro-pastoral area of China. The effects on income and grazing pressure of restricting herd size, prohibiting rangeland reclamation, introduction of sedentary beef production, and credit provision were examined using linear programming in a cropping system and a pastoral system in Inner Mongolia, China. Eight scenarios on land use regulations were compared: unrestricted grazing with or without prohibition of rangeland reclamation, four grazing restrictions (1 or 2 sheep equivalent/ha; 5 or 10 sheep equivalent/person), and two grazing prohibitions (half-year or all year). Complete prohibition of rangeland reclamation and grazing reduced income,but with different effects in the two systems. Rangeland reclamation prohibition reduced income more in the cropping system (-26%) than in the pastoral system (-9%), while grazing prohibition reduced income more in the pastoral system (-55%) than in the cropping system (-14%). Grazing restrictions had little effect on income (0 to -9%) in the cropping system, but more severe restrictions (1 sheep equivalent/ha or 5 sheep equivalent/person) had major negative impact on income (-31% and -30% respectively) in the pastoral system. Introduction of sedentary beef production increased income under all three grazing restriction scenarios in both systems, by 30-42% in the cropping system and 3-18% in the pastoral system, relative to unrestricted grazing without land reclamation. Compared with no credit service, providing credit for poor households of the cropping system to introduce sedentary beef production increased their income by 51%, and increased income for poor households in the pastoral system under the grazing restriction of 1 sheep equivalent/ha by 416%.

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The cultivation and application of Pseuderanthemum palatiferum, a plant found in the latter half of the 1990′s in northern Vietnam, was studied at a total of 12,829 households located in the city center and suburb of Cantho city. The frequency of the households cultivating the plant, the plant′s population and age, recipients, purposes and amount of the dosages were surveyed in interviews with households. Second, growth of the plant at an experimental farm of Cantho University was observed. Only 1.1% of the total households cultivated the plant. However, more (p<0.01) households in the city center cultivated the plant than those in the suburb. More households in the city center cultivated greater populations of the plant. The city center households dosed the plant not only for treatment of human diseases, but also for the prevention and treatment of animal diseases. The frequencies of the dosage and the amount of each dose were more for treatment than for prevention, and more for human diseases than animal diseases. The dosages were more in the city center households. The results of the field study would suggest that cultivation of the plant had been spread from the city center to the suburb, and its dosage had widened from the purpose of treatment to prevention of diseases, and the recipients from human to animal diseases. The plant observed could grow very fast and bloom, in the same way as the growth in northern Vietnam. The easiness of its planting and the earliness of growth would have helped the spread of its cultivation and application in the Mekong Delta region.

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An outbreak of papular stomatitis occurred in a sheep herd in Hokkaido, Japan. Histological examination, immunohistochemistry, electron microscopic observation, and polymerase chain reaction (PCR) were carried out. Lesions were characterized by epithelial hyperplasia, acanthosis, ballooning degeneration of the spiny layer and stratum granulosum. A parapoxvirus was isolated from the skin lesion of affected sheep and characterized genetically and antigenically. Restriction endonuclease analysis of the PCR product showed an orf virus (ORFV)-specific pattern and the isolate reacted with monoclonal antibodies against ORFV. The partially deduced amino acid sequence of the viral envelope gene was identical to those of the major Japanese ORFVs. These results indicated that the outbreak was due to infection by parapoxvirus. The isolated virus could be classified into ORFV, and was closely related to the major Japanese ORFVs, but not foreign ORFVs or other parapoxviruses.

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Two small mountainous sub-watersheds, located at Serikawa river basin on Shikoku Island of Japan were studied for streamwater chemistry. The objective of this study was to determine the impacts of reforestation subsequent to partial logging on streamwater chemistry of the treated sub-watershed compared to the adjacent undisturbed one after several months of reforestation. Both of the sub-watersheds have similar geological and climatic conditions except they vary in size. We collected bulk precipitation and streamwater samples in the pair of sub-watersheds for a period of three years, and analyzed for 10 chemical components (pH, EC, Cl^-, NO₃^-, SO₄^2-, Na⁺, NH₄⁺, K⁺, Ca²⁺, and Mg²⁺). Non-parametric statistical analyses were applied in this study. The pH, EC, SO₄^2-, and cation concentrations in the streamwater were almost unaffected by the reforestation subsequent to partial logging,whereas NO₃^- and Cl^- were sensitive to the forestry activities since their concentrations largely fluctuated in the streamwater of the treated sub-watershed. Results suggested that the increasing NO₃^- and Cl^- concentrations in streamwater caused by the partial logging may be recovered by subsequent reforestation within more or less two years.

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Knowledge of runoff characteristics plays an important role in managing the function of water conservation in the forests. Hydrological observation was conducted at Bukit Tarek Experimental Watershed (BTEW) of a tropical rain forest in Peninsular Malaysia. Stormflow, groundwater recession and stream regimen characteristics were analyzed based on 3-y (1992-1994) of record. Small storm events (< 30 mm) produced less than 10% of rainfall as stormflow, which may have been determined in the stream channel and riparian areas. The stormflow depended strongly on the antecedent wetness as represented by the antecedent flow rate during large storm events (≥ 30 mm). The depth and physical properties of soils could be important factors to determine production of stormflow. The discharge-duration curves were different among 1992, 1993 and 1994 because of the differences of variation in rainfall (e.g. monthly distribution) and annual rainfall. The relationship between ratio of plentiful runoff to scanty runoff and recession coefficient at BTEW was similar to the results from watershed underlain by the same geology in Japan. These results imply that soil, variation in rainfall, as well as annual rainfall and geology are important factors to understand runoff characteristics.

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