Minimization of cannibalism of African catfish (Clarias gariepinus Burchell) larvae in indoor culture system

For minimizing cannibalism of African catfish (Clarias gariepinus) larvae two trials for a period of 14 and 15 days respectively in four aquaria of size 120x49x32 cm³ were conducted. Seven days old African catfish larvae with an initial total length and weight of 7.84 (±0.40) mm and 4.40 (±1.18) mg respectively in the first trial and similarly 7.52(±0.61) mm and 3.98 (±0.56) mg in the second trial at the rate of same stocking densities of 2500 larvae in each aquarium were stocked in both trials. Cannibalistic larvae were separated by using grader frame from each treatment at 7 days and 5 days interval during first and second trial respectively. Two mesh sizes i.e., 5 mm and 7 mm were used in the grader frame in both trials. Survival rate was significantly higher in T1 than that of T2 in each trial. Grading of larvae with 5 days interval resulted higher survival rate than that of 7 days interval

Sustainable agriculture: a challenge in Bangladesh

The sustainability of conventional agriculture in Bangladesh is under threat from the continuous degradation of land and water resources, and from declining yields due to indiscriminate use of agro-chemicals. Government is pursuing efforts to promote sustainable agriculture with emphasis on better use of on-farm resources and the reduction of external inputs. This paper presents four dimensions of agricultural sustainability as productivity, environmental stability, economical profitability, and social and economic equity. Six characters were selected to evaluate sustainability. Significant differences were found between the two systems (conventional and sustainable agriculture) in crop diversification, soil fertility management, pests and diseases management, use of agro-chemicals and environmental issues. However, no significant variations were found in other indicators such as land-use pattern, crop yield and stability, risk and uncertainties, and food security. Although crop yield and financial return were found to be slightly higher in the conventional system, the economic return and value addition per unit of land did not show any difference. It can be suggested that sustainable agriculture has a tendency towards becoming environmental, economically and socially more sound than conventional agriculture, as it requires considerably less agro-chemicals, adds more organic matter to the soil, provides balanced food, and requires higher local inputs without markedly compromising output and financial benefits. Broad-policy measures, including the creation of mass awareness of adverse health effects of agrochemical-based products, are outlined for the promotion of sustainable agriculture

SUSTAINABLE AGRICULTURE: A CHALLENGE IN BANGLADESH

The sustainability of conventional agriculture in Bangladesh is under threat from the continuous degradation of land and water resources, and from declining yields due to indiscriminate use of agro-chemicals. Government is pursuing efforts to promote sustainable agriculture with emphasis on better use of on-farm resources and the reduction of external inputs. This paper presents four dimensions of agricultural sustainability as productivity, environmental stability, economical profitability, and social and economic equity. Six characters were selected to evaluate sustainability. Significant differences were found between the two systems (conventional and sustainable agriculture) in crop diversification, soil fertility management, pests and diseases management, use of agrochemicals and environmental issues. However, no significant variations were found in other indicators such as land-use pattern, crop yield and stability, risk and uncertainties, and food security. Although crop yield and financial return were found to be slightly higher in the conventional system, the economic return and value addition per unit of land did not show any difference. It can be suggested that sustainable agriculture has a tendency towards becoming environmental, economically and socially more sound than conventional agriculture, as it requires considerably less agro-chemicals, adds more organic matter to the soil, provides balanced food, and requires higher local inputs without markedly compromising output and financial benefits. Broad-policy measures, including the creation of mass awareness of adverse health effects of agrochemical-based products, are outlined for the promotion of sustainable agriculture