Satsuma dwarf virus (SDV), Citrus mosaic virus (CiMV), Natsudaidai dwarf virus (NDV), Navel orange infectious mottling virus (NIMV), and Hyuganatsu virus (HV) are widely spread and cause serious damage to citrus production in Japan. SDV also occurs in some parts of China, Korea and Turkey. Biological, serological and molecular characterization of these viruses revealed both inter-relationships among these viruses and relationships with other plant viruses. SDV is a definite virus species in the genus Sadwavirus, and CiMV and other related viruses are classified as strains of SDV. Based on the serological and molecular biological information, useful detection methods utilizing DAS-ELISA, immunochromatographic assay (ICA), and RT-PCR have been developed. These detection methods will promote distribution of SDV-free nursery plants, which is a key control measure. Transgenic rootstocks which harbor coat protein gene and are tolerant to CiMV have also been developed.

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Salmonellosis is associated with massive public health and economic losses globally. It is estimated to cost poultry farmers in the United States of America up to US$114 million annually. Attempts to develop effective vaccines and eradicate Salmonella enterica serovar Enteritidis (S. Enteritidis) from hen houses are undermined by serious limitations. This article reviews documented contamination routes and limitations to the rapid development of vaccines. Host-parasite interactions and clinical pathology are discussed and methods for reducing S. Enteritidis infection and transmission suggested.

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We isolated the 5' upstream promoter regions of the fruit-type sucrose synthase (SS) gene from tomato and Japanese pear by inverse PCR. The 5' region of the tomato SS gene (TOMSSF) contained an intron approximately 1.6 kbp long in the 5'untranslated region, whereas the equivalent 5' region in the Japanese pear SS gene (PypSUS1) had no intron. Each region was fused to the β-glucuronidase (GUS) gene and then each construct (TOMSSF 5'::GUS or PypSUS1 5'::GUS) was used to transform tomato. Histochemical analysis of GUS activity of all transformants showed high GUS activity in the fruit. Analysis of the staining pattern in the fruits of all transformants showed staining specific to vascular tissues and testae. The highest level of GUS activity and GUS mRNA was found in fruits at earlier stages of development in all transformants. However, the increase in the level was not observed in the ripening fruits of PypSUS1 5'::GUS lines, indicating that the expression patterns of PypSUS1 5'::GUS tomato were different from those of PypSUS1 in Japanese pear. It may ascribe to the differences in genetic background between tomato and Japanese pear that relate to the mechanisms contributing to the sucrose synthesis during ripening.

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Effects of an agropastoral system on the production of soybean and wheat were investigated by comparing, from 2003 to 2007, agropastoral plots that had been converted from 7-year pasture (guinea grass: Panicum maximum; 1996 to 2003) to crop cultivation, with control plots that had been continuously cropped over 10 years with soybean at the Japan International Cooperation Agency's Paraguay Agricultural Technology Center (CETAPAR-JICA). Soybean productivity in this area increased from 1979 until 1993, when yield peaked at 3.39 t/ha and then declined. In this study, soybean yields ranged from 1.48 to 3.56 t/ha in agropastoral plots and from 0.63 to 2.47 t/ha in control plots. In each year, the yield in the agropastoral plots was 1.1 to 2.4 times more than in the control plots. Wheat yields were also higher in agropastoral plots (1.59 to 3.17 t/ha) than in control plots (1.18 to 2.31 t/ha). In each year, yield in the agropastoral plots was 1.2 to 1.8 times more than in the control plots. Thus, soybean and wheat yields were sustained by introducing an agropastoral system. We also examined the chemical and physical properties of the soil under initial conditions in both plot types. The concentrations of phosphate, potassium and magnesium in surface soil in agropastoral plots were significantly lower than in control plots. The content of organic matter at soil depths of 0 to 60 cm in the agropastoral plots was significantly higher than in the control plots, and the physical properties of the agropastoral plot soil (gaseous phase, bulk density, and soil aggregates) were improved. We conclude that the agropastoral system positively affected all these properties.

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The biology of the immature stage of Neochrysocharis formosa, a larval idiobiont-endoparasitoid of agromyzid leaf miners, was studied to gain a better understanding of N. formosa and in vitro rearing. Eggs have a smooth surface with a thin, transparent chorion. The length and width are about 190 μm and 60 μm, respectively. Eggs hatched in an average of 32.6 h. Three larval stages are decided by observation of the pre-ecdysis phase. Larvae are hymenopteriform with small mandibles and have 13 body segments. Larval duration at each instar is as follows: 1st instar 35.1 h, 2nd instar 35.7 h and 3rd instar 46.5 h. Mature 3rd-instar larvae escaped from the host and pupated within the mine of the host larvae. Pupal duration was 8 days. The host larvae stopped moving a few minutes after parasitoid oviposition. To examine the oviposition site, longitudinal sections of parasitized host larvae showed all eggs to be within the host’s hemocoel. Fewer eggs were oviposited in the anterior part than the middle and posterior part of the host larvae. No encapsulation or melanization were observed around the parasitoid eggs.

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We clarified the relationship between environmental factors and the growth of seven Eucalyptus species and Casuarina obesa planted at an afforestation site in southern Western Australia's wheatbelt. The site consisted of abandoned fields damaged by secondary salinity associated with waterlogging. Afforestation is expected to progressively rehabilitate the land, which has a slight slope generating a large environmental gradient. During the rainy season, waterlogging (soil becoming saturated with water) occurred at the lower part of the site, but not at the higher part. The level of salt in the soil (EC_1:5) increased gradually from higher to lower ground (0.34—2.7 dS m^-1). Tree size and growth rate were negatively related to waterlogging intensity and showed small values at the lower part of the site, with only a slight effect on tree size and growth rate. Moreover, interspecific differences in size and growth rate were observed. Eucalyptus sargentii and E. occidentalis had larger sizes and faster growth rates than E. camaldulensis. Trees planted under waterlogging conditions at the lower part of the site are likely to fail due to poor growth; therefore, afforestation should begin on higher ground where trees would experience normal growth, and in doing so, reduce the soil water content to rehabilitate the land. Improvement of water balance through afforestation would confirm the benefits of appropriate agroforestry management.

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Asset management is a new concept for operation, maintenance, rehabilitation, and reconstruction of irrigation infrastructure taking into account economic assessment of trade-offs between alternative investment options to help make cost-effective investment decisions. In most countries including developed and developing countries this concept is required mainly due to the lack of financial support from the public sector. In this study, asset management of irrigation infrastructure implemented by corporatized or privatized organizations separated from the state government of New South Wales (NSW), Australia are reviewed to find out essential issues for appropriate asset management of irrigation infrastructure. The viewpoint of business management, discount rate, lifespan of assets, and deterioration forecast are the essential issues for efficient asset management.

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This paper examines the characteristics of a traditional farmer-managed irrigation system in Nigeria, through the presentation of a detailed case study. It documents the development of a traditional irrigation system in the inland valley of the Bida region in central Nigeria and the features of its operation and management. The physical structure and the composition of system users were surveyed in detail. In addition, the characteristics of community management of several irrigation systems in the region were investigated. Farmers were able to mobilize necessary local resources for irrigation development and maintenance although they did this without any external support. The irrigation management institution in the area was highly linked to the local land tenure system. The involvement of landlords in the irrigation community greatly affected the performance of irrigation management. There was no clear definition of water rights. In times of water shortage, water was rotated and shared but water scrambling had become a severe problem in recent years with the higher demand for off-season crops. Irrigation communities were organized informally without tiers of nested organizations. Unfairness in water distribution and contribution to system maintenance existed between top-enders and tail-enders of irrigation canals. Nevertheless, the multi-layered and fragmented land ownership of the region made coordination among different irrigation communities difficult and the unfairness problem could not be solved without institutional changes.

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Heat treatment is commonly used to inactivate micro-organisms in liquid foods in order to improve food safety and extend shelf life. However, using heat treatment to kill spores also thermally damages the food, which can adversely affect the fiavor and lead to loss of nutrients. We have developed an apparatus to apply a high electric field alternating current (HEF-AC) that inactivates heat-resistant microbe spores in liquid food while preserving the freshness of raw food. In this study, HEF-AC was applied to inactivate Bacillus subtilis spores in fresh orange juice. As a result, B. subtilis spores were reduced four logarithmic orders of magnitude. The purpose of this work was to clarify the quality change of treated juice. To achieve this purpose, we used an ultra-high-temperature (UHT) treatment for comparison. Five selected quality components of orange juice treated with HEF-AC maintained higher values than when treated with UHT while having an equal inactivation effect.

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Lavandula × intermedia is cultivated as an ornamental plant in Japan but its fiowering characteristics have not been elucidated. So, a series of experiments were conducted to determine the infiuence of cold treatment and day length on fiowering. An exposure to a 14-week cold treatment (CT) under natural winter condition induced fiowering. An increasing duration of day length was associated with an increase in fiowering rates and with a decrease in days to the first visible bud (VB) and the first open fiower (FLW). This suggests that L. × intermedia may be an essential quantitative long-day plant. When the plants were treated with a low temperature in a cold room at 5°C, a 10-week CT resulted in perfect fiowering. Plants without CT and plants after a 6-week CT did not initiate fioral buds. An increasing duration of CT was also associated with an increase in the rate of fiowering shoots and with a decrease in days to VB and FLW. Thus, exposure to a period of low temperature is the primary factor promoting fiowering in L. × intermedia. Apical dissections and scanning electron microscope (SEM) observations showed vegetative meristems at the end of a 10-week CT at 5°C. Then, dome formation and sepal initiation of the first fioret of each shoot apex were observed at 7 and 21 days after CT, respectively. This suggests that L. × intermedia is a so-called “after effect” fiowering plant. Thus, we conclude that L. × intermedia is a typical vernalization type plant.

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Chickens and domestic ducks were inoculated with highly pathogenic avian infiuenza viruses (H5N1) isolated in Japan in 2007 and 2008. The virus strain A/chicken/Miyazaki/K11/2007 caused 100% mortality in chickens with characteristic skin lesions on the head that were similar to those found in field chicken outbreaks in 2007. The virus strain A/whooper swan/Akita/1/2008 (Ws/Akita/1/08) isolated from dead wild swans was also highly pathogenic against chickens. When domestic ducks were inoculated with each virus, only Ws/Akita/1/08 caused mortality. Two characteristic clinical signs, a neurologic sign and corneal opacity, were observed in domestic ducks. Histologically, edematous and hemorrhagic skin lesions at the comb and wattle were the most prominent findings in dead chickens. In domestic ducks, non-suppurative meningoencephalitis, myocarditis, pancreatic focal necrosis, keratitis, and epidermal necrosis of the feathers and beak were observed, depending on the course of infection. Immunohistochemical testing revealed that, compared to chickens in which the virus preferably replicated in systemic endothelial cells, antigen distribution in domestic ducks was confined to the parenchymal cells of some organs such as the brain, heart, pancreas, and epidermis of the feathers and beak. Our data suggest that, in addition to the increased mortality rate, skin lesions of the head including the wattle and comb comprise an important clinical sign in chickens for detection of highly pathogenic avian infiuenza viruses (H5N1) isolated in Japan. On the other hand, the neurologic signs and corneal opacity can be useful indications for detecting infected waterfowl.

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A simplified method for estimating CO₂ emissions from deforestation is the calculation of carbon stock change by monitoring forest land and periodically summing up the land area and its averaged carbon stock for important forest types. As a feasibility study for applying this methodology to a tropical dry-land forest, we estimated carbon stock and its chronosequential change in 4 carbon pools (aboveground and belowground biomass, deadwood, and litter) of tropical dry-land natural forests in Cambodia. Carbon stock differed among forest types. Most of the carbon stock (84 ± 12% (SD)) existed in tree biomass. Growth of carbon stock has a positive relationship to the carbon stock itself. By moderately classifying forest types, determining averaged tree biomass of each forest type, and using land-area data on each forest type, a reasonably accurate estimation of carbon stock can be expected. However, considering that rapidly progressing deforestation and wood extraction may reduce the carbon stock in forests, systematic sampling with a sufficient number of extra plots and frequent updating of forest land area and averaged carbon stock data are vital for an accurate estimation of CO₂ emissions from forests under pressure of land-use change and forestry activities.

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We have implemented research programs to demonstrate a biomass refinery system for suburban agricultural and livestock industrial areas. We developed a model targeting the Yamada area in Katori City, Chiba Prefecture. The main feedstock biomasses were cow wastes, food processing residues, woody biomass and non-edible portions of farming crops. Elemental technologies such as methane fermentation, gas refining, co-generation, carbonization, concentration of digested liquid, steam explosion, and composting were combined to efficiently produce useful materials and energy, and to minimize both the input of fossil energy to operate elements of plants/units/equipment and the negative impacts of biomass use on the environment. We succeeded in systematic operation of the plants. The biogas produced was refined to methane gas with a concentration greater than 98%. More than 90% of the methane gas from the biogas was collected. It was used as fuel sources for carbonization, co-generation and vehicles to transport biomass. The produced digested liquid was widely used. Systemization of biomass production, collection, transportation, storage, conversion, and use of the converted biomass-derived materials/energy is essential. Achievements of the study provide a pioneering model for local governments all over Japan and other Asian countries to construct biomass towns employing local creativity and ingenuity.

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