To investigate practical scale storage behavior and alkaline digestibility of rice straw for bioethanol resources, the long-term storage test of 98 rice straw bales of which total dry mass was approximately 20 tons at averaged test site in Kanto region in postharvest season, Japan, was carried out. Twenty bales set at bottom position of the test site were decomposed during storage and regarded as low handling materials, which should introduce total cost increase. The pulp yield after digestion of stored rice straw using sodium hydroxide with variable concentrations was 43〜59%, which was smaller than using sodium carbonate 58〜63%. The pulp yield was also related with degree of rice straw crushing. The kappa number of cooked pulp with optimized alkaline chemicals was influenced in storage period.

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This paper estimates the linear approximate almost ideal demand system for meats in Japan using nonstationary time series data. The results of unit root and cointegration tests support the use of the first-difference form. The major estimation results are as follows: The demand for imported meats is more responsive to meat expenditure than that for domestic meats. The discovery of a mad cow in Japan decreased the demand for domestic beef and increased the demand for imported pork. All 6 items are own-price inelastic. Imported beef and domestic pork are Morishima substitutes for domestic beef. Imported chicken is a Morishima substitute for domestic chicken. The paper estimates no significant effects of the elimination of tariffs on meats by the Trans-Pacific Partnership Agreement.

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A novel hydroponic tomato cultivation system was developed on the bases of heat unit-based growth analysis by elaborately integrating two different production systems: triple trusses (3 inflorescences) with high planting density of 6,450 plants/10 a from summer to fall and multiple trusses (8-13 inflorescences) with standard density of 2,150 plants/10 a from winter to spring. Field cultivation trial applying a designed optimum integration pattern from 2008 to 2010 resulted in yearly yield of 42.2 t/10 a, which was 98.1% of the expected yield. These results demonstrate that this is an efficient, highly productive hydroponic tomato cultivation system suitable for Japanese climate, hot and humid summer, that can afford high level of economic return.

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The technology of direct seeding of rice using iron-coated seeds on flooded soil was recently developed and is spreading rapidly in Japan. This study was conducted to clarify the germination characteristics of iron-coated seeds using various rice cultivars. First, germination and seedling emergence characteristics of intact seeds with and without iron coating were examined. The germination coefficient (germination percent / number of days to germination) was reduced by iron-coating and low temperatures in varying degrees depending on the rice cultivar. The germination coefficient of iron-coated seeds significantly correlated with the germination coefficient of non-coated seeds, and with the percentage of seedling establishment in the paddy field. Although the germination coefficient was reduced with the increase in the iron-coating ratio (iron powder weight / seed dry weight), the attack by birds was prevented at the high iron-coating ratio. Secondly, the effects of presoaking of the seed before iron-coating on the germination coefficient were examined. In Koshihikari and Hinohikari, leading cultivars in the mainland of Japan, the presoaking at 20℃ for 3 days or at 13℃ for 6 days increased the germination coefficient of the iron-coated seeds even at low temperatures. However, in three cultivars from Hokkaido, and forage rice cultivar Mihohikari from Shimane prefecture, the presoaking did not always increase the germination coefficient. The effect of presoaking on the germination coefficient was found to vary with the cultivar and with the seed source. Further studies are needed to clarify the adequate presoaking conditions to increase the germination coefficient of iron-coated seeds.

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