ベンガル・デルタ低地部の稲作 : バングラデシュ東部地方におけるアウス・散播アマンの混播栽培とパーボイルド米に関するノート(<特集>渡部忠世教授退官記念号 : 熱帯アジアの稲と稲作)

Abstract

The low-lying areas of the Bengal Delta have unique methods for growing and processing rice. These are the mixed cultivation of aus and broadcast aman and parboiling of rice. These methods are not commonly found in the rice-growing countries in Southeast Asia. The cultivation of aus and its expansion in the Bengal Delta since the late 19th century are discussed based on my field observations in several Districts and a preliminary survey at Chiladi village, Noakhali District from November 1984 to February 1986. The results obtained are as follows : (1) The cultivation of aus varieties has expanded into the deltaic lowland despite their low potentiality in terms of ecological traits. Although this expansion was simply a result of population increase in the delta, it seems to have been made possible by the traditional and sophisticated technologies adopted by the farmers. The methods of harvesting of mixed aus and inter-tillage after the aus harvest in the mixed aman stand show a wide variation from location to location. This wide variation in the mixed cultivation seems to have supported the expansion of aus in the Bengal Delta. (2) Although Bangladesh has a wide variety of rice-cooking methods, most dishes except boiled rice employ non-parboiled aman rice. Aus rice was believed to be the food for poor people and it was not used for ceremonial purposes because of its low degree of sanctity. From these facts it is considered that aus varieties were adopted later than aman varieties in the Bengal Delta. (3) As aus is harvested in the middle of the rainy season, high humidity and wet conditions make processing difficult. Parboiling is indispensable to counter the deterioration of harvested aus rice. The farmers' traditional parboiling method is, therefore, considered to have been effective in expanding aus cultivation in the Bengal Delta.