Department of Agronomy, Faculty of Agriculture Annamalai University, Annamalainagar-608 002 (Tamil Nadu), India.
Studies comprising laboratory, pot culture and field investigations were taken up to study the influence of weed management practices on Rice-Fish Integrated Farming System. The farming system components were rice during two consectuve seasons with or without fish culture. Weed management practices included hand weeding, butachlor, oxyfluorfen and thiobencarb at the recommended rates compared with the unweeded control. Pot culture study to determine the optimum size and time for the release of the fish fingerlings revealed that 4–5 cm long fingerlings released after 12 days of herbicide application gave the highest survival rates. The results of the field experiments revealed that integration of fish culture alongwith oxyfluorfen 0.25 kg ha−1 excelled other treatments with respect of weed control, crop growth and yield. However, use of herbicides caused some tissue deformation in gills, muscle and liver like hyperplasia, epithelial proliferation and congestion of blood vessels, especially in gills, muscle and liver even when the fingerlings were released 12 days after herbicide application. Brain tissue remained unaffected. Rice-fish with oxyfluorfen 0.25 kg ha−1 registered the highest net income for both the seasons.
