To achieve a super high brown rice yield exceeding 10 t ha^-1 in the Tohoku region (relatively cold), a two-year field experiment was conducted. The yield components, morphological traits and dry matter production among the Japonica type high-yield variety “Fukuhibiki,” indica type high-yield variety “Takanari,” large grain type high-yield variety “Bekoaoba” and two conventional Japonica type varieties were compared. Although the traits relating to high yield varied greatly, the three high-yield varieties all showed a large sink size, heavy rice yield at 30 days after heading (30 DAH) and a high harvest index. The effects of nitrogen application and planting density on the morphological traits, dry matter production and yield in the large grain type variety Bekoaoba were investigated. Although high nitrogen application (HN) increased the brown rice yield from 8 to 9.5 t ha^-1, regulation of the timing of topdressing and/or planting density under HN could not increase the brown rice yield beyond 10 t ha^-1. Strategies to achieve a super high-yield rice in the Tohoku region were discussed.

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In the Kyushu region, located in southern Japan, the area of paddy rice cultivated for whole- crop silage (WCS) and grain feed is increasing rapidly and has exceeded 8,000ha. At the Kyushu Okinawa Agricultural Research Center (KARC), various paddy rice varieties for WCS and grain feed have been developed in response to cultivation types in this region. “Makimizuho” is a WCS variety featuring early maturity and enabling cultivation in a dual-crop system. “Mogumoguaoba” is a variety with strong culm and high yield, making it usable for both WCS and grain feed. “Tachiaoba” is a high-yield variety for WCS with late maturity. “Ruriaoba” shows superior productivity under twice-harvested cultivation. “Mizuhochikara” is a variety with high grain yield and superior lodging resistance. These varieties are expected to help boost the feed self-sufficiency ratio in Kyushu.

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Recent epidemiological studies have suggested the adverse effects of an excess intake of trans fatty acids on human health. This study investigates the relation between the formation of trans fatty acids and heating. The mechanism of heat-induced cis/trans isomerization was first resolved by using the model lipids (triacylglycerols). Then the formation of trans fatty acids in edible oil during heating and frying were examined to accurately evaluate the content of trans fatty acids found in fried or heated food.
When one kind of unsaturated triacylglycerol—triolein (9-cis, 18:1)—was heated at around 180°C, small amounts of isomerization products dependent on heating temperature and heating period were obtained. Heat-induced isomerization is strongly correlated with the thermal oxidation of double bonds. And several edible antioxidants such as δ-tocopherol, sesamol, and rosemary extract effectively suppressed heat-induced trans isomerization.
In comparison with triacylglycerols, many small formations in trans fatty acids were observed in commercially available several edible oils when heated at around 180°C. The antioxidants coexisting in each edible oil also help suppress the formation of heat-induced trans fatty acids.
A frying model system was then used to estimate increases in trans fatty acids during cooking. Sliced raw potatoes (100 g) were fried in commercially available corn oil at 180°C, and 30 frying cycles were performed. A small change in the content of trans fatty acids in the frying corn oil suggests that an ordinary frying process using unhydrogenated edible oils has little impact on the dietary intake of trans fatty acids.

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A series of studies were performed to determine the effects of increasing environmental temperature and relative humidity on the performance of Holstein heifers. In heifers of 200 kg body weight, the effects on dry matter intake and daily weight gain were small at 28°C and 60% relative humidity, but dry matter intake and daily weight gain were seen to start declining at 28°C and 80% relative humidity. Moreover, in heifers of 400 kg body weight, even at relative humidity of 60%, dry matter intake and daily weight gain started to decline at 28°C. At 60% relative humidity, the rate of decline in daily weight gain in heifers of 200 kg body weight at 33°C was similar to that of those of 400 kg body weight at 28°C. These results indicated that the influence of high temperature on the performance of heifers intensified at a late stage, and under high relative humidity. An assessment of the impact of global warming on heifer growth performance in the Japanese summer was made using ‘Climate change 10 × 10 km mesh data (Japan)’, which is one of the models assuming progressive global warming. In the 2060s, compared to the end of the 20^th century, areas showing a decline in the rate of body weight gain in heifers will expand from Kanto to the western Hokkaido area, and the rate of decline will accelerate over time from the present to the 2020s, 2040s and 2060s, especially in July and August. As high humidity under hot temperatures significantly affect heifer growth, global warming and high humidity in the Japanese summer will have the negative effect.

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Sugarcane production in Japan dropped to a record low of 1,186,000 tons in 2004. Severe drought and tropical storms (typhoons) often reduce sugarcane yields. In order to avoid these environmental stresses, an early harvest system and early maturing cultivars are required. The maturing characteristics of one early maturing clone (“KY96T-547”) were thus investigated in breeding experiments to clarify effective methods of identifying early maturing clones. The results of spring planting crops in a regular breeding program and autumn planting crops intended for early harvest were also analyzed. Among the spring planting crops, the early maturing clone exhibited earlier increases in brix value at the top position of the stem, with higher orders of brix for this clone also being observed at the top. The coefficient of variance for the top brix among approximately 50 clones was higher than that for other stem positions. The coefficient of variance was higher at the beginning of October, when the brix values of early maturing clones increased. This is the best time for screening at the research site . Among the autumn planting crops, the early maturing clone matured October or November at the same level as in the regular harvest season.

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Soybean is a crop known to be susceptible to flooding and enhancing flooding tolerance may be a workable strategy to improve soybean production. To elucidate the effects of flooding on soybean metabolism, metabolite alterations in seedlings during flooding treatment were identified using capillary electrophoresis-mass spectrometry (CE/MS). The principal component analysis (PCA) of soybean seedlings revealed that the first component accounted for 62.2% of total variance, and the alteration of metabolites in control and flooding treatments appears to be separated by this component. Furthermore, comparison of the metabolic loading scores in the first component of PCA show that the significant metabolites for the first component were alanine (Ala), gamma-aminobutyric acid (GABA), citrate, fumarate and malate. Quantitative analysis revealed that the total soluble sugar content of seedlings in both control and flooding treatments had declined and was lower in the latter than the former. Phosphoenolpyruvate, pyruvate and lactate, which belong to glycolytic and fermentation pathways, increased transiently, but decreased 3 to 4 days after treatment. Citrate, 2-oxoglutarate, succinate, fumarate, Ala, and GABA, which are related to the TCA cycle and amino acid metabolism, accumulated during flooding treatment. These results suggest that metabolism associated with the TCA cycle, the Ala synthetic pathway, and the GABA shunt may be strongly influenced by flooding during soybean germination.

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An alternative production system to slash-and-burn cultivation is urgently required to satisfy both increasing subsistence needs and environmental conservation objectives in the rainforest region of Madagascar. This paper investigates the current land-use management practices of smallholder farmers that have faced tight land-use pressures due to rapid population growth and stricter forest protection laws. Spatio-temporal patterns of land use were analyzed for lowland and hillside households by using data obtained from a ground survey of 316 fields. Both household groups retained longer fallowing periods for upland rice cultivation (lasting 5.4 to 6.8 years) than those previously reported (of 3 to 5 years). Recent dynamic changes in the agricultural systems included bottomland saturation with irrigated paddies and a rapid transition of coffee-growing areas into slash-and-burn and terraced paddy areas, in order to meet subsistence needs. A shift in dependence from slash-and-burn cultivation to lowland paddies was particularly significant among lowland households due to the expansion of terraced paddies and adoption of a double-cropping system in the irrigated lowlands. The hillside households intensified cassava cultivation in short-term fallowing periods, as also reflected by their high dependence on cassava for caloric consumption. The difference in countermeasures adopted by both household groups to deal with land-use pressures was partly due to the accessibility to extension services. The results suggest that such intervention to promote intensification in lowland paddies was apparently an effective approach to reduce dependence on slash-and-burn cultivation. Given the limited land areas in which to further expand paddy fields, higher crop productivity is needed in the future to achieve a smooth transition to an agricultural system not dependent on slash-and-burn practices.

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A zero energy cool chamber (ZECC) consisting of a brick wall cooler and a storage container made of new materials has been developed. The ZECC requires no electric energy. The brick wall cooler made of bricks with a mixture of moistened sand and zeolite allows low inside temperature and high relative humidity to be maintained based on the principles of a natural evaporative cooling mechanism. Several types of storage containers coated with different antibacterial materials were applied to reduce decay. For example, silver-ion-coated storage containers were used to reduce decay. Heat treatment was also applied to the commodities in order to maintain freshness. Generally, tomato and eggplant had a shelf life of 7 and 4 days at room temperature, respectively, as compared to 16 and 9 days when stored in the ZECC. Tomato and eggplant treated with hot water reduced the percentage of rotting. Tomato treated with hot water at 60°C for three minutes and eggplant treated with hot water at 45°C for an hour when stored inside silver-ion-coated containers in the ZECC showed extended shelf life of up to 28 and 15 days, respectively.

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Inflorescence refers to the spatial and temporal patterns of flowers and analysis of the branching pattern would facilitate understanding of the entire structure of inflorescence. To gain an insight into the inflorescence architecture of Eustoma, the popularity of which has soared worldwide, we conducted a detailed characterization of inflorescence development. In particular, we focused on identifying meristem types and describing their development, both of which may affect the inflorescence structure. During reproductive development, the shoot apical meristem usually splits into two meristems, either or both of which can become inflorescence meristems and capable of producing a floral meristem. However, the inflorescence meristems ultimately abort flower production. Meanwhile, axillary meristems sometimes grow and convert into inflorescence meristems, leading to differentiation of floral meristems. Hence, different types of inflorescence result from different types of meristem, and changes in meristem activity. We elucidated the factors influencing inflorescence structure and classified them into eight groups.

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