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The unequal distribution of gains from technology between favorable and unfavorable rice environments in Asia can widen if future transgenic rice varieties cannot be adopted in less favored regions. This study investigates the potential economic impacts of three transgenic rice technologies: stemborer resistance, for favorable irrigated environments; drought resistance, for unfavorable non-irrigated environments; and herbicide resistance, which can potentially benefit any of the environments but can only be adopted in areas under direct seeding. Specifying individual technologies contributes to a better comparative assessment of impacts from transgenic rice. The simulation uses a modified version of the Global Trade Analysis Project (GTAP) model with several innovative features: the database and code represent the distinct rice environments for both paddy and seed sectors; monopoly power is included in the model as a markup tax instrument when private firms sell herbicide resistant rice seed; and private rents can be transferred between regions and change income computation in the model. Equivalent variation measures obtained from simulations are similar at 2.3 billion, 2.5 billion and 2.2 billion dollars for stemborer, drought and herbicide resistance respectively. All technologies increase global rice output and reduce rice prices, while keeping labor wages at stable levels. Private provision of herbicide resistance rice generates benefits of 2.05 billion dollars while creating 122 million dollars in private profits. Although profits increase with higher markups, there are still large social benefits to realize from herbicide resistance technology. However, producers' response to reduced profitability is not accounted for and adoption is an exogenous variable in the model. The results suggest that the large expected impact from drought resistant rice supports public research investment on this technology. Joint efforts between public and private research sectors can increase the probability of success, and mechanisms to promote private research for unfavorable environments should be developed. Public policies should also remove obstacles that prevent firms from undertaking joint research with the public sector. Outcomes from public research, such as improved germplasm and spread of direct seeding techniques, also benefit the private sector and should act as an incentive for firms to build strategic alliances. / Ph. D.

The Mekong River Basin (MRB) is famous for its rice farming and export and produces more than 20 million tons of rice per year. Rice production depends on climate, irrigation, soil fertility. However, this region is adversely impacted by several environmental concerns like nutrient deficiency from sediment and saltwater intrusion. The decrease in sediment deposition in the Mekong basin is caused by a number of factors. In China, Lao PDR, and Vietnam, the hydropower generation from dams has improved people's overall living standards, leading in more dams being built or planned in the future. However, dam construction work is adversely impacting the overall salinity condition in this region by reducing upstream flow. Upstream lower flows during the dry season contributes to the increased salinity in the lower Mekong Delta. In addition to these, multiple dams in the upper and middle region of the Mekong basin are trapping sediments and decreasing it in the lower zones. This study found that the reservoirs, built by China between 2008-2015, has reduced the sediment load at all five stations considered in the study. When a reservoir is removed from the model, the sediment load is increased which showed the substantial impact of reservoir construction on sediment load in this area. The landuse pattern is another factor for variability of the sediment yield in the study area. Forest area contributes to higher sediment production whereas agricultural area results in lower sediment yield. The GFDL RCP (4.5) and GFDL RCP (8.5) future climate change projection scenarios used in this study also demonstrated substantial variability in the precipitation pattern for the study region. GFDL RCP (4.5) scenario resulted in a lower sediment yield during the dry season. On contrary to that, GFDL RCP (8.5) showed higher sediment yield due to higher precipitation during the wet season. The severe salinity impact was observed in the Cai Nuoc, Nam Can, and Thanh Phu districts. In Ca Mau province, the observed salinity is highest among the provinces of the study area during dry season (February to May), about 12-14 PPT (parts per thousand) whereas the lowest level of salinity (less than 1 PPT) was observed in the Dong Thap and Vinh Long provinces. This salinity intrusion is adversely impacting the rice production in the study area. In the year 2000, rice production in the Ca Mau province was about 100-150 thousand tons. But salinity intrusion is drastically reducing the rice production in this area, about 10-30thousand tons per year during 2015-2017. Rice production is increasing in the upper deltaic part of the Mekong Delta region where preventive measures were taken. / Master of Science / The Mekong River Basin (MRB) is famous for its rice farming and export and produces more than 20 million tons of rice per year. The rice production is governed by rainfall, temperature, irrigation, soil fertility etc. However, this region is adversely impacted by multiple environmental concerns like nutrient deficiency, sediment concentration, and salinity. The decrease in sediment deposition in the Mekong basin is caused by several factors. In China, Lao PDR, and Vietnam, the hydropower sector has improved people's overall living standards. As a result, more reservoirs are being constructed or planned to be constructed in the future. But this dam construction work is adversely impacting the overall salinity condition in this region. Upstream flows rate during the dry season (February to May) contributes to the increased salinity condition in lower Mekong Delta. In addition to these, multiple dams in the upper portion of the Mekong basin are trapping sediments and decreasing it in the lower region. From the analysis performed in this study it was found that the reservoirs, built by China between 2008-2015, has reduced the sediment load at all five stations. When the reservoir is removed from the model, the sediment load is increased implying the substantial impact of reservoir construction on sediment load in this area. The landuse pattern is another dominating factor for variability of the sediment yield in the study area. Forest area contributes to higher sediment production whereas agricultural area results in lower sediment yield. Two future climate projection scenarios considered for this study are the GFDL RCP (4.5) and GFDL RCP (8.5). These two scenarios also demonstrated substantial variability in the precipitation pattern for the study region. The severe salinity impact was observed in the Cai Nuoc, Nam Can, and Thanh Phu districts. In Ca Mau province, the observed salinity is highest among the provinces of the study area during dry season (February to May), about 12-14 PPT ((parts per thousand) whereas the lowest level of salinity (less than 1 PPT) was observed in the Dong Thap and Vinh Long provinces. This salinity intrusion is adversely impacting the rice yield in the study area. In the year 2000, rice production in the Ca Mau province was about 100-150 thousand tons. But salinity intrusion is drastically reducing the rice production in this area, about 10-30thousand tons per year during 2015-2017. Rice production is increasing in the upper deltaic part of the Mekong Delta region where preventive measures were taken.

Rice bacterial leaf streak disease caused by Xanthomonas oryzae pv. oryzicola (Xoc) is one of the most important rice bacterial diseases. Xanthomonas type III effector gene avrRxo1 is conserved in diverse Xoc strains and its homologues have been identified from several other gram-negative bacteria species such as Burkholderia and Acidovorax. In this research, we studied the protein structure of AvrRxo1 and illustrated its virulence mechanism.We determined the three-dimensional structure of the complex of AvrRxo1 and its cognate chaperone Arc1 (AvrRxo1 required chaperone 1). The AvrRxo1: Arc1 complex is structurally similar to the Zeta-epsilon family of toxin: antitoxin systems from the human bacterial pathogen Streptococcus pyogenes. AvrRxo1 and Arc1 have toxin: antitoxin-like activity in bacteria, and the toxin activity of AvrRxo1 is required for its virulence function in planta. These findings suggest that AvrRxo1 evolved from an endogenous bacterial toxin-antitoxin system.Furthermore, AvrRxo1 was shown to have virulence functions in diverse host plants including Arabidopsis thaliana. The ectopic expression of wild type avrRxo1 in Arabidopsis suppresses plant basal defense. AtVOZ (Arabidopsis vascular one zinc-finger transcription factor), which has two homologues in the Arabidopsis genome, VOZ1 and VOZ2, was identified as one of AvrRxo1 candidate interactor. The knockout of voz1/voz2 renders the plants more susceptible to the virulent pathogen Pseudomonas syringae pv. tomato (Pst) DC3000, but compromises the virulence function of AvrRxo1. The expression profiling of transgenic Arabidopsis plants expressing the avrRxo1 gene allowed us to identify Arabidopsis genes regulated by AvrRxo1 and VOZ1/2. AvrRxo1 interacts with and stabilizes VOZ2 in vivo and directly binds to the promoter region of AtCYS2 (Arabidopsis phytoCYStatin 2) to induce its expression. The overexpression of CYS2 in increased stomatal aperture size, and enhanced plant susceptibility to Pst. Therefore one of AvrRxo1 virulent functions is to regulate the expression of CYS2 by manipulating VOZ2, resulting in increased stomatal aperture. Presumably, this renders the host leaf more susceptible to colonization via the stomata. Another component of my dissertation was based on a genome-wide survey of Arabidopsis papin-like cysteine protease genes (PLCPs). The Arabidopsis genome has 31 PLCP and 7 cystatin genes, and they often worked in pairs to regulate signaling pathways in response to biotic and abiotic stress. The coordinated transcriptional regulation of all Arabidopsis PLCP and cystatin genes has never been systematically investigated. In order to unveil the mechanism of stomata-related plant immunity regulated by CYS2, we analyzed the expression patterns of 28 PLCPs and 7 cystatins in Arabidopsis in response to biotic or abiotic stress, by reprocessing and integrating microarray data from the AtGenExpress database. We also performed enzyme assays and evaluated the inhibition specificity of seven cystatins to the five most abundant PLCPs in Arabidopsis. Finally, we utilized the SVMs (support vector machines) package in R software to predict a functional network of PLCP-cystatin interplay in Arabidopsis. We identified the PLCP protein PAP4 as one of the putative targets of CYS2. The co-expression profiling indicated that the expression patterns of PAP4 and CYS2 were strongly correlated during virulent bacterial infection, and weakly correlated under drought stress. Therefore, PAP4 was determined to be a promising gene in regulating stomatal aperture size. Further research on the interplay of PAP4-CYS2 could be important for understanding AvrRxo1's virulence mechanism and regulation of plant stomatal immunity. / Ph. D.

Rice production plays an important role in the economy of the Mekong River Delta (MRD), but rice production is endangered by sea-level rise and the associated increased incidence of salinity intrusion. This study examines the diffusion of salt-tolerant rice varieties (STRVs) in the MRD that were promoted through Consortium for Unfavorable Rice Environment (CURE) activities. Evidence is found of widespread adoption in salinity-prone areas, with CURE related varieties covering 47% of rice area in at least one of two growing seasons surveyed, but that adopting areas are highly clustered. Multivariate analysis reveals that location characteristics associated with high risk of salinity inundation, rather than individual characteristics associated with household risk preferences, explain the observed pattern of adoption in the MRD. In particular, CURE-related varieties are disproportionately likely to be adopted in non-irrigated areas and in irrigated areas that are not protected by salinity barrier gates. The results imply that CURE has effectively targeted unfavorable rice growing environments and that efforts to further diffuse STRVs need to both increase the area of suitability through further varietal adaptation and promote adoption in existing suitable areas by taking advantage of strong neighborhood externalities in household adoption decisions. In terms of varietal performance, inconclusive evidence is found of higher yields of CURE-related varieties in a low-salinity year. Further, any yield gains are more than off-set by lower market prices for CURE-related varieties. / Rice is a staple crop in the Vietnamese diet and one of Vietnam's leading exports. The Mekong River Delta (MRD) accounts for more than 90 percent of rice exports. However, rice production in the MRD is endangered by saltwater intrusion due to rising sea-levels. Farmers have adopted rice varieties that are tolerant to rice to reduce their production risk that were promoted through Consortium for Unfavorable Rice Environment (CURE) activities. This study examines the rates of adoption of these CURE-related varieties, the reasons farmers choose CURE-related varieties, and variety performance on farmers' fields. Results from a household-level survey show at 47% of fields in salinity-prone areas of the MRD grow a CURE-related variety in at least one of the areas two main rice-growing seasons. Farmers are particularly likely to adopt CURE-related varieties on fields that are not protected against salinity intrusion by gates. Adoption decisions are also highly correlated with neighbors’ decisions within villages. Finally, CURE- and non-CURE-related varieties yields are similar in a year with low levels of salinity intrusion. But revenues from CURE-related varieties are slightly lower due to their lower market price, suggesting CURE-related varieties are a relatively low-cost insurance policy for MRD rice farmers in salinity-prone areas against future salinity intrusion.

A procedure was developed to estimate optimum irrigation requirements for lowland rice cultivation in Southeast Asia. The procedure uses a water balance equation of semi-stochastic nature to maintain minimum desired water depths in paddy fields at the end of each irrigation period. The procedure estimates weekly pan evaporation (EV) and rainfall (RF) at different probability levels, which is then used to determine weekly irrigation requirements at different probability levels. To illustrate the use of the method, the Kalawewa irrigation scheme in Sri Lanka was selected for demonstration purposes. Different transformations were applied to Rf and EV data in an attempt to normalize these variates and to obtain a unique distribution to describe their variations. Statistical analysis of weekly EV arid RF showed that the power transformation was best able to transform the weekly RF and EV data to normality. Comparison of the use of the model and current system practices showed that a significant amount of water could be saved even when the system was operated at high probability levels (90% reliability). The irrigation water required when the system was operated at the 72% probability level was about 21% less than the amount required when the system was operated at 90% probability level during some weeks. The EXTRAN flow routing model was used to simulate water flow in the upper reaches of the main canal system for varying discharges at the head gate each day. The simulated water depths were used to determine the gate settings required at the turnout structures to divert the desired amount of irrigation water into the turnout areas. The flow simulation for the demonstration area, showed that it was not possible to regulate irrigation water from the main reservoir to meet daily demands at all the turnouts. This was due to the large distances between the regulating reservoir and turnouts that caused appreciable time lag for the flow to reach the turnouts farthest from the regulating reservoir. / Ph. D.

The present study analyzes the economic impact of the introduction of Genetically Modified Organisms (GMOs) in Uruguay's agriculture. Using a partial equilibrium framework the impacts of transgenic varieties are simulated for two crops, rice and potatoes, in small open and closed economies respectively. The model accounts for the presence of market imperfections created by the monopolistic behavior of the genes' patent owner. The change in economic surplus generated after the adoption of the new technology is projected to be positive, although the seed markup charged by the monopolist reduces the surplus compared to a perfectly competitive market. Total deadweight losses and domestic losses are found to increase with the seed premium, as additional monopolist profits are extracted out of the country. Adoption decreases with the seed premium, further reducing the domestic consumer and producer surplus. The results of the study suggest an active role for national technology policies and for the agricultural R&D system in Uruguay to generate conditions that attract the technology's owner to a small market while at the same time reducing the potential losses that monopoly power creates . / Master of Science

京都大学 / 新制・課程博士 / 博士(農学) / 甲第25348号 / 農博第2614号 / 新制||農||1108(附属図書館) / 学位論文||R6||N5520 / DGAM / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 近藤 直, 准教授 小川 雄一, 教授 野口 良造 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

Call number: LD2668 .T4 1986 C52 / Master of Science / Geology

Submitted by Marlucy Farias Medeiros (marlucy.farias@unipampa.edu.br) on 2018-09-27T20:33:58Z No. of bitstreams: 1 ANTÔNIO RODRIGUES PETTERLE- 2018.pdf: 2305522 bytes, checksum: 69cc82567d353c585b3c2aad186edee3 (MD5) / Approved for entry into archive by Marlucy Farias Medeiros (marlucy.farias@unipampa.edu.br) on 2018-09-27T21:03:54Z (GMT) No. of bitstreams: 1 ANTÔNIO RODRIGUES PETTERLE- 2018.pdf: 2305522 bytes, checksum: 69cc82567d353c585b3c2aad186edee3 (MD5) / Made available in DSpace on 2018-09-27T21:03:54Z (GMT). No. of bitstreams: 1 ANTÔNIO RODRIGUES PETTERLE- 2018.pdf: 2305522 bytes, checksum: 69cc82567d353c585b3c2aad186edee3 (MD5) Previous issue date: 2018-03-01 / Placas cerâmicas prensadas foram obtidas a partir de misturas com diferentes proporções contendo argila caulim, sílica extraída da casca de arroz após queima em temperatura controlada e lodo de estação de tratamento de águas (LETA). Propriedades físicas como densidade aparente, absorção de água e porosidade, propriedades mecânicas como resistência à compressão, e propriedades térmicas como condutividade térmica das placas cerâmicas após queima (Norma DIN EN12667) foram avaliadas. A sílica quando inserida na argila caulim propicia aumento da fase vítrea, redução na fase porosa, redução de condutividade térmica e aumento de resistência mecânica. O uso do LETA quando inserido na massa cerâmica propicia aumento considerável dos picos de mulita e de cristobalita, expressivo aumento de porosidade e diminuição das resistências térmica e mecânica. As placas cerâmicas com traço de mistura contendo 80% argila caulim, 20% sílica de casca de arroz e 10% LETA apresentaram o menor valor de condutividade térmica na placa cerâmica após queima de 0.2574W / mK, e a maior resistência à compressão de 189.97 MPa quando comparada aos demais traços testados. Em função dessas propriedades termomecânicas, as placas cerâmicas com esta formulação foram aplicadas como revestimento em uma parede de alvenaria em escala real com dimensões 1,20 m de largura x 2,20 m de altura, sendo submetida ao ensaio de calor e choque térmico (ABNT NBR 15575). O desempenho a durabilidade indicou que a placa cerâmica contendo está formulação tem potencial para ser utilizada como revestimento em fachadas de edifícios. O resultado do ensaio de durabilidade não apresentou nenhuma degradação tais como: deformação, fissuras ou desnivelamento, e apresentou um deslocamento horizontal de 1,13 mm, sendo este um valor abaixo do estabelecido na norma NBR 15575 que prediz 8 mm para uma altura de 2,40m. / Pressed ceramic plates were obtained from mixtures with different proportions containing kaolin clay, silica extracted from the rice husk after burning at controlled temperature and sludge from a water treatment plant (LETA). Physical properties such as bulk density, water absorption and porosity, mechanical properties such as compressive strength, and thermal properties as thermal conductivity of the ceramic plates after firing (DIN EN12667) were evaluated. The silica when inserted in the kaolin clay provides an increase in the glassy phase, reduction in the porous phase, reduction of thermal conductivity and increase of mechanical resistance. The use of the LETA when inserted in the ceramic mass provides a considerable increase of the mullite and cristobalite peaks, expressive increase of porosity and decrease of the thermal and mechanical resistances. The ceramic plates with a mixture trace containing 80% kaolin clay, 20% silica rice husk and 10% LETA showed the lowest value of thermal conductivity in the ceramic plate after burning of 0.2574W / mK, and the highest compressive strength of 189.97 MPa when compared to the other traits tested. Due to these thermomechanical properties, the ceramic plates with this formulation were applied as a coating on a real-scale masonry wall with dimensions 1.20 m wide x 2.20 m high, being submitted to the heat and thermal shock test (ABNT NBR 15575). The durability performance indicated that the ceramic plate containing this formulation has potential to be used as coating on building facades. The results of the test of durability did not present any degradation such as: deformation, cracks or unevenness, and presented a horizontal displacement of 1,13 mm, being this a value below that established in norm NBR 15575 that predicts 8 mm for a height of 2 , 40m.