Sri Lanka achieved a high level of self-sufficiency in rice in the 1980s through a series of investments on irrigation, technological change, and marketing and trade policies. However, more than two decades of expansion in the international rice market has diminished the validity of rice self-sufficiency policies as an economic development strategy. As a consequence, trends in the international market through their impacts on reducing investments such as rice research, extension, and irrigation development have adversely affected the ability of Sri Lanka to maintain the same levels of rice self-sufficiency in the future. In the domestic policy area however, some degree of indecision exists in undertaking reforms necessary to take advantage of the trends in the international rice economy. Given the overwhelming influence rice has on the direction of national agriculture policies in Sri Lanka, it is critical to resolve this indetemlinacy pertaining to rice policies. The objectives of the present study are to estimate the producers' response to numerous policy variables that impact on the levels of rice production, and the country's ability to manage food-security under a regime of market-friendly policies. A supply response model based on the choice of technique approach with endogenous determination of technology was specified to capture the effects of policy variables on rice output determination. The dynamic effects of technology, prices, and investments on productivity are therefore accounted for in the model. The supply response system is composed of blocks of equations for determination of investment in quasi-fixed inputs, choice of technology, and yields. Data for the period since 1974 during which notable changes took place in the rice supply situation in Sri Lanka were used in the analysis.. Results suggest that a major share of rice output growth in Sri Lanka is explained by the producers' response to government-supplied, technology-related variables such as irrigation and research. Rice supply response to input and output prices was slight relative to the response to technology variables. Model simulations showed that, under a regime of more market friendly policies, continuation of current investment trends and policies would lead to a worsening of rice self-sufficiency levels over the next 10 years. It was also observed that with modest growth in irrigation and research investments, it is possible to maintain rice self-sufficiency at levels comparable to the present. / Ph. D.

Le riz est devenu une denrée de grande consommation au Bénin et les études prospectives le présentent comme la céréale qui sera la plus consommée en Afrique de l’Ouest dans les prochaines décennies. Malgré le potentiel rizicole dont dispose le Bénin et les stratégies nationales de promotion du riz, l’offre domestique est faible par rapport aux ambitions affichées par ce pays de parvenir à la souveraineté alimentaire. Cette thèse vise à analyser les mesures de politiques de souveraineté alimentaire en matière de riz dans une perspective de sécurité alimentaire durable. Des enquêtes exploratoires et approfondies ont été réalisées auprès des riziculteurs. Des données quantitatives et qualitatives ont été collectées à l’aide de questionnaires et guides d’entretien. Les résultats de cette recherche montrent que le riz local dispose d’un avantage comparatif par rapport au riz importé. Cependant, des efforts doivent être faits pour réduire les coûts de production afin de rendre le riz malanvillois plus compétitif. Le niveau d’instruction, l’accès au crédit, l’expérience en riziculture et le statut social du producteur peuvent contribuer à améliorer le taux d’adoption des technologies et augmenter la productivité. Une politique rizicole combinant simultanément une politique de soutien du prix, de subvention d’engrais spécifiques au riz, de culture attelée et agricole climato-intelligente augmenterait la production et permettrait de parvenir à la souveraineté alimentaire. / Rice has become a primary consumed product in Benin. Studies have revealed it will become the most consumed cereal in west Africa within the next decades. Despite the resources Benin possesses favouring rice culture and the government measures to promote it, the household supply remains unsatisfactory when compared to the objective set by the country to reach food sovereignty. The present essay analyses the government policies in order to reach a sustainable food sovereignty through rice culture. In depth, exploratory surveys have been conducted among the rice farmers. Qualitative and quantitative data was collected through structured questionnaires and guided interviews revealing the comparative advantage local rice has over imported one. Efforts have yet to be made in order for Malanville rice famers to reduce their production costs and become more competitive. Education level, access to loans, rice farmers experience as well as their social status are the key factors influencing the implementation of new technologies allowing an increase of productivity. Rice production and food sovereignty should be attained by implementing simultaneously income support policies, funded fertilizers, climate-smart culture and ploughing by oxen.