Tuyển tập các báo cáo nghiên cứu khoa học của trường đại học cần thơ trên tạp chí nghiên cứu khoa học đề tài: KHÍA CẠNH KỸ THUẬT VÀ HI ỆU QUẢ KI NH TẾ CÁC MÔ HÌNH CANH TÁC LÚA - CÁ VÀ LÚA ĐỘC CANH Ở VÙNG DỰ ÁN THỦY LỢI Ô MÔN - XÀ NO. | Tạp chí Khoa học 2008 2 176-187 Trường Đại học Cần Thơ KHÍA CẠNH KỸ THUẬ T VÀ HI ỆU QUẢ KINH TẾ CÁC MÔ HÌNh canh tác lúa - CÁ VÀ LÚA ĐỘC CANH Ở VÙNG DỰ ÁN THỦY LỢI Ô MÔN - XÀ No Nguyễn Thị Thanh Nga1 Lê Xuân Sinh2 ABSTRACT This study was conducted from October 2006 to April 2007 in the districts relating to O Mon-Xa No irrigation sub-project and belong to Can Tho City Hau Giang and Kien Giang provinces. The result showed that the application of rice-fish farming techniques was still simple water level on the platform was about average stocking density was 0 49 fish m2 at the average size of g fish. Fourteen different species of fish were stocked in rice-fish system but common carp and silver barb were the most common species covering about 55 and of the total number of fingerlings respectively. Almost fish were not fed during the stocking duration. Average fish yield was ton ha year for 2 crop rice-1 fish system and that of 3 crop rice-1 fish was ton. Average total cost for 2 crop rice-1 fish system was million dongs which helped to bring about million dongs of profit and a Benefit Cost ratio of times. These figures for 3 crop rice-1 fish were million dongs million dongs and . The results of multiple regression analysis revealed that the farmers could improve the yield of fish and rice as well as the profit of rice-fish systems if they applied a better level of investment and farming practices. Particularly area of the systems was about ha 2 crops of rice with average amount of rice seed was 600 kg ha the stocking densities of fish was 1-2 fish m2 of which silver barb was about 20-40 of total number offingerlings and common carp was at the same number to double amount of silver barb the water level on the platform was kept at 20-30 cm fish was feed using by-products of agriculture at the quantity of 1-2 ton ha year the quantity of fertilizers was tones ha year the costs of pestiside .