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Shimizu T.,Japan National Agricultural Research Center | Ogamino T.,Japan National Agricultural Research Center | Ogamino T.,Ibaraki University | Hiraguri A.,Japan National Agricultural Research Center | And 7 more authors.
Phytopathology | Year: 2013

Rice grassy stunt virus (RGSV), a member of the genus Tenuivirus, causes significant economic losses in rice production in South, Southeast, and East Asian countries. Growing resistant varieties is the most efficient method to control RGSV; however, suitable resistance genes have not yet been found in natural rice resources. One of the most promising methods to confer resistance against RGSV is the use of RNA interference (RNAi). It is important to target viral genes that play important roles in viral infection and proliferation at an early stage of viral replication. Our recent findings obtained from an RNAi experiment with Rice stripe virus (RSV), a tenuivirus, revealed that the genes for nucleocapsid and movement proteins were appropriate targets for RNAi to confer resistance against RSV. In this study, we transformed rice plants by introducing an RNAi construct of the RGSV genes for the nucelocapsid protein pC5 or movement protein pC6. All progenies from self-fertilized transgenic plants had strong resistance against RGSV infection and did not allow the proliferation of RGSV. Thus, our strategy to target genes for nucleocapsid and movement proteins for conferring viral resistance might be applicable to the plant viruses in the genus Tenuivirus. © 2013 The American Phytopathological Society.

Sato-Izawa K.,Tokyo University of Agriculture and Technology | Nakaba S.,Tokyo University of Agriculture and Technology | Tamura K.,Kyushu Okinawa Agricultural Research Center | Yamagishi Y.,Tokyo University of Agriculture and Technology | And 9 more authors.
Plant, Cell and Environment | Year: 2012

Rice internodes are vital for supporting high-yield panicles, which are controlled by various factors such as cell division, cell elongation and cell wall biosynthesis. Therefore, formation and regulation of the internode cell-producing intercalary meristem (IM) are important for determining the shape of internodes. To understand the regulation of internode development, we analysed a rice dwarf mutant, dwarf 50 (d50). Previously, we reported that parenchyma cells in the elongated internodes of d50 ectopically deposit cell wall phenolics. In this study, we revealed that D50 encodes putative inositol polyphosphate 5-phosphatase (5PTase), which may be involved in phosphoinositide signalling required for many essential cellular functions, such as cytoskeleton organization, endocytosis and vesicular trafficking in eukaryotes. Analysis of the rice genome revealed 20 putative 5PTases including D50. The d50 mutation induced abnormally oriented cell division, irregular deposition of cell wall pectins and thick actin bundles in the parenchyma cells of the IM, resulting in abnormally organized cell files of the internode parenchyma and dwarf phenotype. Our results suggest that the putative 5PTase, encoded by D50, is essential for IM formation, including the direction of cell division, deposition of cell wall pectins and control of actin organization. © 2012 Blackwell Publishing Ltd.

Ohtsu H.,National Institute of Livestock and Grassland Science | Yakabe Y.,National Institute of Livestock and Grassland Science | Yamazaki M.,National Institute of Livestock and Grassland Science | Yamazaki M.,Kyushu Okinawa Agricultural Research Center | And 2 more authors.
Journal of Poultry Science | Year: 2013

Ketone bodies such as β-hydroxybutyrate and acetoacetate have physiological functions in addition to being used as an energy source. In order to assess the effect of elevated ketogenesis on blood lipid profiles and redox status, a ketogenic diet (KD), a high-fat, low-carbohydrate, and low-protein diet, was fed to chicken for 4 weeks. Plasma β-hydroxybutyrate, but not acetoacetate, concentrations were significantly increased by KD feeding for 2 and 4 weeks. The KD also induced elevation of plasma non-esterified fatty acid (NEFA) and total cholesterol concentrations, whereas plasma triglyceride concentration was decreased. Plasma total antioxidant activity in chicken with ketosis induced by KD was lower than that of the control. However, the level of plasma TBARs, an oxidative stress marker, was also reduced by KD feeding. A reduction of energy intake was observed in chickens fed the KD; therefore, the effect of a restricted diet (RD) was also investigated. Plasma β-hydroxybutyrate concentration, lipid (total cholesterol and NEFA) concentration, and redox status were not affected by RD feeding. These data suggest that a high-fat, low-arbohydrate, and low-protein diet induces ketosis by elevating blood β-hydroxybutyrate concentration in chicken. Under conditions of ketosis induced by the KD, total antioxidant capacity was reduced along with a modulation of the blood lipid profile in chicken. © 2013, Japan Poultry Science Association.

Sugiura R.,Japan National Agriculture and Food Research Organization | Omine M.,Kyushu Okinawa Agricultural Research Center | Watanabe T.,Kyushu Okinawa Agricultural Research Center
Transactions of the ASABE | Year: 2012

When handling a vehicle trajectory dataset composed of a large number of points on a digital map, all the collected data may not be required. In particular, when a trajectory is displayed on a computer screen, it is desirable to use the smallest dataset that can accurately describe the actual trajectory. The objective of this study is to develop an algorithm that reduces the amount of vehicle tracking data while retaining the original shape of the vehicle trajectory. The algorithm assigns a degree of importance in shape representation to each data point. The degree of importance is defined in terms of wavelet coefficients, and the algorithm determines the order by which data points are eliminated. To evaluate the performance of the algorithm, a 15,618-point dataset obtained from a GPS unit mounted on an agricultural vehicle was processed. Even when the dataset was reduced to 912 points, which is only 5.8% of the original dataset, the root mean square error was no more than 0.76 m. The computational time for data reduction on the selected computer was 8 ms. The proposed reduction algorithm was embedded in the map software used to display the vehicle trajectory. © 2012 American Society of Agricultural and Biological Engineers.

Sanada-Morimura S.,Kyushu Okinawa Agricultural Research Center | Otuka A.,Kyushu Okinawa Agricultural Research Center | Matsumura M.,Kyushu Okinawa Agricultural Research Center | Etoh T.,Saga Prefectural Agriculture Research Center | And 3 more authors.
PLoS ONE | Year: 2015

Overseas migration of the small brown planthopper, Laodelphax striatellus (Fallén), occurs during the winter wheat harvest season in East Asia. Knowing the take-off time of emigrating L. striatellus is crucial for predicting such migrations with a simulation technique because winds, carriers of migratory insects, change continuously. Several methods were used in China and Japan from late May to early June 2012 and again in 2013 to identify the precise timing of take-off. These methods included: a tow net trap mounted to a pole at 10 m above the ground, a helicopter-towed net trap, and a canopy trap (which also had video monitoring) set over wheat plants. Laodelphax striatellus emigrated from wheat fields mainly in the early evening, before dusk. The insects also emigrated during the daytime but rarely emigrated at dawn, showing a pattern that is unlike the bimodal emigration at dusk and dawn of two other rice planthoppers, the brown planthopper, Nilaparvata lugens (Stål), and the white-backed planthopper, Sogatella furcifera (Horváth). There was no significant difference in the temporal pattern of take-off behavior between females and males of Japanese L. striatellus populations. © 2015 Sanada-Morimura et al.

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