RICE WITH FISH CULTURE IN THE SEMI-DEEP WATERS OF THE MEKONG DELTA, VIETNAM - INTERACTION OF RICE CULTURE AND FISH HUSBANDRY MANAGEMENT ON FISH PRODUCTION

Fish husbandry and rice culture management factors influencing the yie ld of introduced fish in ricefields of the Vietnamese Mekong Delta wer e studied by multiple regression analysis, A significant (P < 0.001) r egression model was computed in which feed input and duration of cultu re period positively, and ricefield area, rice seeding rate and the ye ar of the survey negatively affected the yield of introduced, as well as indigenous, fish. The negative impact of larger ricefields is proba bly the result of the escape of fish. This is also probably the reason for the year of survey since the average yield of introduced fish was 92.5 kg hal in 1995 (because of an extreme flood) as compared to 164. 8 kg ha(-1) in 1994. A high seeding rate of rice results in a dense st and which suppresses the growth of fish. Opportunities for improvement of fish production are proper ricefield construction, reduced seeding rates, stocking fingerlings early in the dry season and more intensiv e feeding.