Common buckwheat plants have heteromorphic self-incompatibility. Using two self-fertilizing lines, we revealed that there are two distinct systems of self-compatibility, one using a self-compatible allele, S^h, the other using modifier genes located outside the S locus and suppressing the functions of the S-locus genes. S^h appears to have been produced by recombination in the S supergene (gi^SI^PPA/gi^SI^PPA), in which each gene is functional. The modifier genes control the intensity of self-incompatibility and have three distinctive features: (1) Pollen shows cross-compatibility with styles of all flower types, although the compatibility is influenced by the genetic background of those plants. (2) Flower morphology of F₁ plants is controlled by the genotype of the S locus. (3) F₁ plants show high self-compatibility, although the level of self-compatibility is influenced by genetic background. The use of these genes for buckwheat breeding is discussed.

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We investigated the effects of root-zone environment, humidity around the roots and nutrient solution on the activity and morphology of tomato roots grown in wet-sheet culture (exposed to air) or deep flow technique (submerged in solution). Differences in root external and internal structure between treatment groups could be interpreted as adaptive responses to the root environment. The exposed roots could adapt more readily to extremes of temperature than those in the solution. Those adaptations occurred through short-term physiological responses and long-term additive morphological responses. We also evaluated the facilitating effects of the flow of nutrient solution on root respiration and nutrient uptake rate. Where the root system was split between humid air and nutrient solution, roots in the solution absorbed and supplied nitrogen more efficiently per dry weight than did roots in air. Split root systems between humid air and nutrient solution showed stable growth of tomato plants. Our observations of root plasticity will help the establishment of growing systems that support high yield and stable production.

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Sanitation efficacy of prewashing with acidified sodium chlorite (ASC) for the production of lightly fermented Chinese cabbage was evaluated. The treatment of raw cut Chinese cabbage with ASC for 15 min significantly reduced the level of pathogens without causing apparent changes in color. The population of natural microflora on the leaves was reduced by about 2.0 log CFU/g just after washing with ASC, which is significantly better than what was achieved with a control distilled water wash (P ≤ 0.05). In a control experiment, viable aerobic bacteria increased gradually when incubated at 10°C, however, ASC washed cut Chinese cabbage maintained a lower microbial level. The treatment of cut Chinese cabbage with ASC reduced the population of artificially inoculated Escherichia coli O157:H7, Salmonella Enteritidis, Staphylococcus aureus, and Listeria monocytogenes by 2.4 log CFU/g. The sanitation efficacy of ASC was 1.6 log CFU/g higher than that of distilled water washing. The viable cell counts of all pathogenic bacteria tested remained constant during 8 days of storage at 10°C for both washing treatments with the exception of L. monocytogenes. In the case of L. monocytogenes, the viable cell counts after ASC washing treatment increased gradually with time. No significant difference in color, odor, taste, and texture change in raw leaves or fermented ones was observed with an ASC wash compared to a distilled water wash. These results suggested that prewashing with ASC could control the bacterial growth in lightly fermented Chinese cabbage without changing its quality.

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The authors describe how farmers of Jawar village, which is located on the fringe of a large inundated area (haor) in Bangladesh, engage in agriculture and try to evaluate their traditional agricultural techniques. The farmers of the village cultivate a high yield variety (HYV) aman rice in high-elevation fields, a local variety (LV) in low-elevation fields and both varieties in medium-elevation fields to fit the ordinal water condition of the rainy season. In a flooding year they transplant LV aman rice even in parts of medium- and high-elevation fields where HYV is transplanted under ordinal circumstances in order to be well adapted to the dynamic hydrological condition. Aman rice cultivation in Jawar village is used to cope with flooding and water receding and the dry field crop (rabi) area increases in the following dry season to recover from losses in rice production of the former rainy season. Total rabi cultivated area of a flooding year is two times larger than that of the year before flooding, especially mustard cultivated area is three times larger. It can be said the farmers implement two countermeasures to increase crop production security; selecting a local rice variety in the rainy season and increasing rabi cropping area in the dry season have been adapted to meet the dynamic hydrological condition.

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The IRRI-Japan Collaborative Research Project has been developing new sets of differential varieties for resistance to blast disease (Pyricularia grisea Sacc.) in rice (Oryza sativa L.). The first international standard differential variety set composed of monogenic lines for 24 kinds of resistance genes (Pia, Pib, Pii, Pik, Pik-h, Pik-m, Pik-p, Pik-s, Pish, Pit, Pita, Pita-2, Piz, Piz-5 (= Pi2), Piz-t, Pi1, Pi3, Pi5(t), Pi7, Pi9, Pi11(t), Pi12(t), Pi19(t), and Pi20) was released and has been widely used in various countries. Furthermore, the project has been developing near-isogenic lines (NILs) for blast resistance with three kinds of genetic backgrounds, a Japonica-type variety Lijiangxintuanheigu (LTH), an Indica-type variety CO39, and a newly developed ‘universal susceptible’ line US-2 which was derived from a cross between Indica and Japonica-type susceptible varieties. A total of 23 lines for 14 kinds of resistance genes, Pia, Pib, Pik, Pik-h, Pik-s, Pita, Pita-2, Piz-5 (= Pi2), Piz-t, Pi1, Pi3, Pi5(t), Pi7, and Pi9, have been developed by the recurrent backcross method using the monogenic lines with the LTH genetic background. Twenty lines for 14 kinds of resistance genes, Pib, Pik, Pik-h, Pik-m, Pik-p, Pik-s, Pish, Pita, Pita-2, Piz-5 (= Pi2), Piz-t, Pi1, Pi5(t), and Pi7 have been developed with the CO39 genetic background. Moreover, a universal susceptible rice line, US-2, which has not been known to have any blast resistance genes in the genetic background, and can be cultivated easily under both tropical and temperate conditions, is also being used for the development of NILs as the next generation of differential varieties. These lines are offered as gene sources for breeding of blast resistance and as sets of international standard differential varieties used for the study of blast disease.

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Solar radiation in a rice canopy plays an important role in the energy balance on both the plant leaves and soil/water surface. A simple model was derived from the two-stream model to estimate two important factors characterizing radiation in a plant canopy, namely, transmissivity of the canopy (τ_c ) and the albedo of the canopy (ref), from the absorption coefficient of leaves (α) and leaf inclination factor (F). To clarify the seasonal variation in α and F with growth, season-long observations were conducted in paddy fields during three different cropping seasons. Values of α were almost constant throughout the growing period; however, values of F tended to increase with growth. Values of F were larger than 0.5 (the theoretical value for random leaf distribution) in the late growth stage mainly due to the alterations in leaf geometry with the change in leaf inclination angle along a more horizontal axis after flowering, while in contrast, values of F were less than 0.5 in the early growth stage mainly due to the distribution bias of leaves after transplanting. Seasonal variation in F during different cropping seasons could commonly be expressed as a function of developmental stage (DVS). Using this function, τ_c and ref could be estimated with more accuracy. The proposed radiation model and function is expected to be applicable in more accurate evaluation of solar radiation, dry matter production and soil/water temperature in paddy fields.

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An experiment was conducted with the objective to investigate the influence of available water deficit in typical soil types on the yield and crop water requirement of soybeans in Indonesia. This research was conducted in a plastic greenhouse of the University of Lampung from June to August 2005. A factorial experiment was arranged in randomized block design with three replications. The soil type (S) was the first factor with two different soil types, Ultisol (S1), and Latosol (S2). Water deficit (D) was the second factor with five levels including D1 (0-20%), D2 (20-40%), D3 (40-60%), D4 (60-80%), and D5 (80-100%) of water deficit from the total available water (TAW). For example, D1 (0-20%) meant that water was given to maintain the available water depletion between 0% and 20% of TAW in the root zone. Yield under full irrigation in Ultisol (21.3 g/pot) was 2.3 times as much as in Latosol (9.3 g/pot). Yield efficiency (the ratio of yield to crop water requirement) in Ultisol was the greatest under deficit irrigation of 30% of available water deficit (0.0083 g/g), which was 1.26 times as much as under full irrigation (0.0066 g/g). However, yield efficiency of Latosol was the greatest under full irrigation (0.0049 g/g). Therefore, yield efficiency of soybean in Ultisol was 1.8 times as much as in Latosol.

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Using the CFD model, a new ventilation system design will be found later taking into consideration the ventilation efficiency such as uniformity, stability, and suitability of environmental factors in a naturally ventilated broiler house. Because conducting a field experiment for the ventilation study presented so many difficulties, a reliable 3-dimentional computational fluid dynamics (CFD) model had to be developed to investigate the natural ventilation. Before investigating its accuracy, a wind tunnel and particle image velocimetry (PIV) test was initially conducted to find their best experimental conditions and improve the PIV accuracy^13,15. A 1/20 scale model of a naturally ventilated broiler house was used to get qualitative and quantitative airflow distribution in the broiler house using the PIV and CFD. To improve the CFD accuracy, the PIV and CFD computed airflows in the broiler house were compared, particularly on the distribution, local air velocity, and turbulent intensity in the house. The quality of the mesh density and the design of the boundary condition, especially the wind velocity and turbulence profiles, were found to be very important for getting accurate results. Assuming the PIV results were accurate, the most accurate CFD results were obtained when using a RNG k-ε turbulence numerical model. The average error of the CFD computed air velocity when using the RNG k-ε models was -6.2%.

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Cucumber plants contain a bitter substance, cucurbitacin C. The compound was isolated from cucumber leaves using preparatory HPLC (high performance liquid chromatography) to investigate the relationship between its content and bitterness of the plant parts. An analytical method for cucurbitacin C using HPLC was also established. A Japanese popular cultivar, ‘Sharp 1’ contained the compound in the leaves but not in the fruits, while a unique cultivar with white skin ‘Shinsyo Hakuhi’ contained it both in leaves and fruits. The stem end of ‘Shinsyo Hakuhi’ fruit contained higher amounts of it than other fruit parts. Cucurbitacin C is a strongly bitter component and its threshold level was less than 0.1 mg/L. The bitter sensation felt when biting the plant parts could be interpreted as corresponding to the content of cucurbitacin C.

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An outbreak of Nipah virus infection occurred in 1998 in Malaysia in which a total of more than 1 million pigs were culled and 109 people died from this disease. Samples were collected from frugivorous bats living in Malaysia that were considered to be a natural reservoir of Nipah virus. There were two kinds of fruit bats, the so-called flying fox and the small fruit bat. Samples were collected from small fruit bats and flying foxes caught by mist net traps. No antibody and no Nipah virus were detected from the samples of small fruit bat. However, an average 18% and 63% positive for antibody were detected from the samples of flying foxes living in the islands (Island flying fox) and peninsula of Malaysia (Malayan flying fox), respectively. Nipah virus was not isolated from either of the flying foxes. However, Nipah virus gene was detected from Malayan flying fox by real-time PCR. Reovirus like virus and other unknown viruses were isolated from Malayan flying foxes. From these results, flying fox was an important natural reservoir of Nipah virus and especially Malayan flying fox was considered to be more important as a natural reservoir.

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Lymphoma with large granular lymphocyte (LGL) morphology in a heifer is described. The most noticeable macroscopic finding was neoplastic involvement of the skin, mucosae of the alimentary tract, urinary bladder, and uterus. Histologically, lymphoma cells with large numbers of fine eosinophilic granules predominated in the neoplastic tissue, and the granules were positive for perforin. Surface CD3, CD5 or WC1 was expressed by some neoplastic cells. In addition to the epitheliotropism that is a feature of ordinary γδ T-cell lymphoma, the neoplastic cells showed angiodestruction and erythrophagocytosis. These phenomena were thought to result from marked activation of neoplastic γδ T-cells. The present lymphoma was distinct from the previously reported bovine NK-like T-cell lymphoma in its tissue distribution, cytomorphology, cytochemistry, and immunophenotype. Since this lymphoma was regarded as a cytologic variant of γδ T-cell lymphoma, the term hypergranular γδ T-cell lymphoma seemed to be more appropriate than γδ T-cell LGL lymphoma.

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This paper analyzes the development of China′s wood processing industry since the start of the economic reform in 1979. The paper examines self-sufficiency rates and trade specialization coefficients of wood products and undertakes a correlation analysis for the period from 1979 to 2004, and specifies production functions of wood products from 1990 to 2004. The paper finds that self-sufficiency rates for wood products have a similar course of development as they decreased first and then increased later with increases in production, imports and exports. Within the wood processing industry, plywood holds the highest self-sufficiency rate, but sawnwood holds the lowest. The industry has a low international competitiveness, except for plywood which has a comparative advantage in international trade, as shown by trade specialization coefficients. The correlation analysis shows that there is a high correlation between the production of plywood, fibreboard, and particle board panels. The production functions show that in decreasing order, sawnwood, plywood, fibreboard, and particle board have proportional increases in production with each unit of roundwood supply at the shares of the domestic supply of roundwood, 34, 33, 19, and 14%, respectively. Furthermore, in this analysis imported roundwood helps the production of wood panels grow faster than the domestic roundwood supply does.

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Susceptibility of orange-spotted grouper Epinephelus coioides, Asian sea bass Lates calcarifer, mangrove red snapper Lutjanus argentimaculatus, milkfish Chanos chanos, and rabbitfish Siganus guttatus to piscine nodavirus from orange-spotted grouper was studied by experimental infection. The fish were intraperitoneally injected with 0.05 mL of the filtrate homogenate of infected organs from diseased grouper at 10^6.8, 10^5.8 or 10^4.8 TCID₅₀ /fish, while the control group received 0.05 mL of Hanks′ balanced salt solution. Clinical signs such as lethargy, anorexia and darkened pigmentation were observed in the orange-spotted grouper, Asian sea bass, mangrove red snapper, and milkfish injected with high and medium doses of the homogenate. Although no or little mortality occurred in the experimentallyinfected fish 10 days post-inoculation, viral nervous necrosis specific lesions such as severe necrosis and vacuolation in the brain and retina were produced in these four fish species. The virus was reisolated in SSN-1 cells inoculated with the filtrated tissue homogenate of survivors in all doses for all four fish species. However, in the experimentally infected rabbitfish no histological lesion was observed, and no virus was reisolated. These results indicate that grouper, sea bass, mangrove red snapper, and milkfish are susceptible to the piscine nodavirus isolated from diseased grouper.

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