Useful novel floral traits have recently been generated in various ornamental crops by using Chimeric REpressor gene Silencing Technology (CRES-T). CRES-T is a plant-specific gene silencing method that targets transcription factors (TFs), causing a dominant loss-of-function phenotype. In our group project, we applied CRES-T to various ornamental crops and mainly elucidated the following points: 1) CRES-T was effective for the modification of floral traits, 2) it was useful in higher polyploidy crops, and 3) it enabled the creation of commercially valuable flowers. In CRES-T, the attachment of a short repression domain derived from a transcriptional repressor to the C-terminal region of target TFs converts transcriptional activators to dominant chimeric repressors. In the target flower species, some Arabidopsis chimeric repressors were effective for the production of new floral traits without cloning the TF genes of interest. Therefore, the use of Arabidopsis chimeric repressors could be widely effective for many ornamental crops, even when the genome and/or expressed sequence tag (EST) information of target crops is unavailable or lacking. In addition, the collective transformation of chimeric repressors into ornamental crops is effective in isolating useful and/or target floral traits, such as petal colors, petal shapes, and color patterns. This technology could help to accelerate the developmental period and reduce the cost of developing new floral traits.

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Crop rotation between irrigated paddy rice (Oryza sativa L.) and upland soybean [Glycine max (L.) Merr.] (paddy-upland rotation) induces a decline in soil nitrogen (N) fertility, as observed by available soil N. There was a significant negative correlation between the available soil N and the proportion of upland seasons to total crop seasons after the initiation of paddy-upland rotation (upland frequency).The decline in soil N fertility was alleviated by the application of organic materials. Soil total carbon also tended to decrease with an increase in upland frequency. Soil physical properties were affected by the paddy-upland rotation. As soil organic matter decomposed in paddy-upland rotation, the soil density increased with decreasing soil porosity. A suitable range of available soil N for paddy-upland rotation was identified between 80 and 200 mg/kg, the same as for paddy rice. The keys to controlling soil N fertility in paddy-upland rotations are the upland frequency and application of organic materials. To sustain the available soil N over the minimum suitable level of 80 mg/kg, the upland frequency should not exceed approximately 60% when only crop residues and no other organic materials are applied. The upland frequency can be increased by the repeated application of organic materials, thereby maintaining a higher level of available soil N.

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Mechanisms underlying the effects of organic amendments on the metabolites in vegetable crop plants remain unclear for the most part. Organic fertilizers are believed to help produce “high quality” vegetables; however, the relationships between organic amendment and vegetable quality are not understood.We took a metabolite profiling approach that comprehensively analyzed both the major and minor constituents of plants. Manure amendments consistently affected the metabolite composition of various vegetable organs in field experiments. Moreover, it was shown that both manure and organic fertilizer amendment caused clear metabolic changes in pot experiments using mizuna (Brassica rapa L. var.Nipponsinica). It is suggested that the amendment of organic matter does indeed influence metabolite composition in vegetables. Further research is needed on the mechanisms responsible for changes in metabolites and on the factors affecting the quality characteristics of foods.

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Semiarid climate regions have great potential for productivity due to large amounts of solar radiation throughout year. However, these regions also have disadvantages, such as excessive air temperature and limited water use. Optimizing the ventilation rate and evapotranspiration during fog cooling in combination with natural ventilation will provide more favorable growing conditions for plants in a semiarid climate and allow less water use. A single-span greenhouse at The University of Arizona was used to investigate the fog cooling performance on clear days with excessively high air temperature.The environmental conditions and the natural ventilation rate were measured. The performance of fog cooling in combination with natural ventilation was compared with pad-and-fan cooling. Fog cooling and pad-and-fan cooling used 24 g m^-2 min^-1 and 41 g m^-2 min^-1 of water, respectively. The air relative humidity for fog cooling was slightly higher than that for pad-and-fan cooling, at approximately 35%.An English version of Visual VETH (ventilation-evapotranspiration-temperature-humidity) software was also developed. A cooling strategy devised for semiarid greenhouses found that the air relative humidity inside a greenhouse decreased with an increase in ventilation rate as expected from simulation based on steady-state energy balance equations, while the water use for fog cooling increased.A simple and unique control algorithm for fogging and ventilation inlet openings demonstrated the possibility of maintaining relative humidity and air temperature simultaneously within a desirable range while reducing the water use for fog cooling. The tomato plant canopy transpiration rate and the water balance relative to the natural ventilation rate in a fog-cooled greenhouse were also investigated. The transpiration rate increased linearly with an increase in vapor pressure deficit (VPD) of the air. At a lower ventilation rate made possible by reducing the ventilation inlet openings, total water use in the greenhouse decreased by 13% and relative humidity increased as was expected from the steady-state energy balance simulation. The decrease in canopy transpiration resulted from the decrease in VPD, and was at a magnitude greater than that of the fog evaporation rate under similar experimental conditions with relatively high humidity in the range of 70-94%. By optimizing the natural ventilation rate, the greenhouse could be effectively cooled with less water use. Arizona can be considered a model analogous to many other semiarid climate conditions. Due to the long history of greenhouse technology development, the application of greenhouse crop production to an area with excessive radiation and dry air remains a relatively new effort. We believe that our efforts will contribute not only to the American Southwest but also to enhancing the application of greenhouse technology for crop production in these climate regions worldwide, including Mexico, China, the Middle East and Africa.

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Declining in reproductive efficiency is a worldwide problem, although remarkable progress has been made in reproductive techniques including artificial insemination programs, estrous cycle synchronization, and effective embryo production. One means of solving this problem is to select breeding cows based on highly precise diagnosis for high reproductive ability, including ovarian and uterine function. Many recent studies have documented the regulation of uterine function, with the results suggesting that said functions might be an effective diagnostic index for reproductive performance. Therefore, the production of oxytocin-induced prostaglandin F_2α and epidermal growth factor in bovine endometrium, such as the physiological reaction in vivo, may be useful in detecting repeat breeder cows. Although the diagnosis is possible using relatively simple techniques such as biopsy, culture, and hormone assay, it is difficult to apply such diagnosis to the field conditions. However, further improvements in the exhaustive gene expression analysis of uterine function in repeat breeder or low fertility cows, so as to determine the genes associated with physiological reactions, could lead to new diagnostic indexes resulting in improved reproductive efficiency.

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One of the longest rivers in the world, the Mekong River flows through eight estuaries into the East Sea off Vietnam. In recent decades, the complex morphological evolution of the Mekong River Delta coast has affected the livelihoods of local people and the development of Vietnam’s major economic area in the south. In this study, large-scale numerical models were created to simulate the long-term morphological processes along the Mekong River Delta coast. By using these models, key factors such as river currents, tides, sediment discharge, monsoon currents, waves, and salinity were calculated under various conditions, including seasonal variations of river flow, monsoon surface sea currents, and waves. The results show that the river flow rate determines erosion and deposition in the river. Furthermore, the river current combined with tidal current governs the development of narrow passages and islets. The effect of the interaction between the monsoon current and waves on the morphological processes of the coastline is significant. The monsoon current plays a major role in changing the shoreline, whereas wave action is a secondary factor that intensifies shoreline erosion, which is primarily influenced by sea current.

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Increasing attention has been focused on promoting the physical and psychological health of non-farmers through farm activities such as home gardening and allotment gardening. In addition to these two farm activities, another farm activity — assisting with farm tasks — has been recently observed among non-farmers. Assuming that certain activities promote the health of non-farmers, specifically assisting with farm tasks near the home, allotment gardening, home gardening, walking, hiking, light physical exercise, home training with gymnastic equipment, and bowling, the preference for assisting with farm tasks compared to other farm and non-farm activities for health promotion was assessed among non-farmers in Chiba prefecture, Japan. Based on the best-worst scaling approach, assisting with farm tasks and allotment gardening were found to be the least and second-least preferred activities, respectively, while home gardening was found to be more preferred than these two farm activities. According to our results, decreasing farm task difficulty, reducing the travel cost of visiting a farmer, and asking non-farmers to only assist with tasks that can be conducted at their own pace could increase the non-farmers’ preference for assisting with farm tasks as a method of health promotion.

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The net photosynthetic rate on a per-plant basis of the Oriental hybrid lily ‘Siberia’ was low at the leafing stage but increased rapidly at the visible flower bud and flowering stages. The range of 20 to 25°C was the optimum temperature for photosynthesis at the three plant developmental stages under PPFD of 700 to 850 µmol photons m^-2 s^-1. The respiration rate increased with the increasing temperature quadratically (in aerial plant parts) or exponentially (in underground parts). The ‘Siberia’ plants were grown under three day temperature (DT) conditions of 28°C, 24°C or 20°C, with a night temperature (NT) of 15°C or three NTs of 25°C, 20°C or 15°C, with DT of 25°C in the growth chambers. At the flowering stage, the plants grown under low DT of 20°C had a high dry weight (DW) of the total plant, flowers, bulb, and roots, and a high DW/fresh weight (FW) ratio of the leaves, stem, and bulb. The plants grown under low NT of 15°C had a high DW of the total plant and stem, and a high DW/FW ratio of the leaves and bulb. The plants that were grown under a low NT had a long stem length by the positive DIF effect, which was supported by sufficient dry mater accumulation. The plants grown under low DT of 20°C showed a high relative growth rate (RGR) and net assimilation rate (NAR) from planting to flowering, whereas the NT condition did not affect the RGR or NAR.

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To reduce the intake and accumulation of dioxins and dioxin-like compounds in nursing beef calves, the concentrations of seven polychlorinated dibenzo-para-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), and 12 dioxin-like polychlorinated biphenyls (PCBs) were analyzed and compared in the natural milk of grazing beef cows and bovine milk replacers, and in the blood, testis, and adipose tissue of mother-fed and bottle-fed calves at two months of age. The total toxic equivalent quantities (TEQs) of these compounds were approximately tenfold less (P < 0.001) in synthetic milk substitute and starter feed for calves than in natural milk (1.0 and 0.88 vs. 9.28 pg/g-lipid, respectively). The TEQ in the blood of mother-fed calves increased (P < 0.01) two months after birth (1.35 vs. 8.44 pg/g-lipid), whereas no difference in TEQ was found in bottle-fed calves between birth and two months of age (0.94 and 0.93 pg/g-lipid, respectively). Consequently, TEQs in the blood, testis, and adipose tissue were less (P < 0.05) in bottle-fed calves as compared with mother-fed calves at two months of age (0.93 vs. 8.44, 4.97 vs. 21.7, and 5.17 vs. 18.1 pg/g-lipid, respectively). Regarding individual congeners, the concentrations of dioxins with four or five chlorine substitutions were lower (P < 0.05) in synthetic milk substitute and starter feed than in natural milk, whereas the concentrations of hepta- and octa- chlorinated congeners were conversely higher in synthetic milk substitute and starter feed. Similarly, the accumulation of tetra- and penta- chlorinated congeners in adipose tissue of bottle-fed calves was lower (P < 0.01) than that in mother-fed calves. In contrast, congener specific accumulation characteristics like PCDDs were not observed in PCDFs and dioxin-like PCBs, and none of these congeners detected in bottle-fed calves were greater than that found in mother-fed calves. These results suggest that the feeding of milk replacers can markedly reduce the intake and accumulation of dioxins and dioxin-like compounds in nursing beef calves as compared with natural feeding, because the milk replacers contain preferably lower concentrations of these compounds than in natural milk.

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Lao People’s Democratic Republic (Lao PDR) submitted a request to Japan for 200,000 doses of expired foot-and-mouth disease (FMD) O type vaccines that were in storage for emergency use. Approximately 100,000 animals, consisting of both cattle and Asian water buffalo (Bubalus bubalus bubalis), received the same vaccine twice within one month in Xieng Khouang province in the northeast area of Lao PDR. Concurrently, the efficacy of three-month expired FMD O type vaccine (6PD₅₀ O Manisa) was assessed in serum samples of 90 cattle and 31 buffalo from the field using a Liquid Phase Blocking-ELISA (LPBE) assay. Of these samples, 75 cattle (83.3%) and 24 buffalo (77.4%) were seropositive against the FMD virus (FMDV) O type before vaccination. Testing for non-structural protein (NSP) using the PrioCHECK FMD NS kit showed that many of the animals with high titers in the screening test before vaccination were FMDV-infected animals. Fifteen cattle and seven buffalo with titers 1:32 or under before vaccination exhibited high titers of antibody (1:45-1:1448) one month after the first vaccination and further increased titers (1:362-1:5792) one month after the second vaccination. Nearly all of the cattle (97.6%) had high titers to control FMD 14 months after the second vaccination. To date, no outbreak of FMD has been reported at the study site. Three-month expired FMD O type vaccines induced appropriate immune responses against FMD in both cattle and buffalo.

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Nasal eosinophilic granuloma in two cases involving a 13-month-old Japanese Black heifer (case 1) and a two-year-old Japanese Black heifer (case 2) is described. The animals suffered from bilateral nasal obstruction, with the nasal cavities being occupied by large tumor-like masses. In case 1, the nasal mucous membrane was largely thickened due to severe eosinophilic infiltration; in case 2, there were many plasma cells and eosinophils. Epithelioid cells with bacterial organisms were observed in both animals. Extracellular eosinophilic deposits of Splendore-Hoeppli material, formed between intact filamentous bacteria and live epithelioid cells, appeared to be elongated spicules and resembled those in actinomycosis. In contrast, in a separate case of Trueperella pyogenes infection, neutrophils containing intact rod-shaped bacteria showed coagulation necrosis and fusion, and finally transformed into sulfur granules without projections on the surface. These differences suggest that at least two types of Splendore-Hoeppli phenomenon occur in bacterial infections.

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