author(s)
Preetam Kala, Krishna Kanta Tamuli, Sushanta Borthakur and Sarda Kanta Bhagabati

abstract
An experiment on the effect of different stocking densities of mola (Amblypharyngodon mola) on the growth of Indian Major Carps (IMC) was conducted for 90 days. Four treatments (T_0, T_1, T₂ and T₃) in triplicates were tried. Catla, Rohu and Mrigal fingerlings were stocked at the rate of 8000 nos. ha^-1 in 2:2:1 ratio respectively in each treatment. Mola were stocked at the rate of 15,000 nos. ha^-1, 25,000 nos. ha^-1, and 35,000 nos. ha^-1 in treatment T_1, T₂ and T₃ respectively_. T_0, with only IMCs, served as the control. Highest production was obtained in T₁, followed by T₀, T₂ and T₃ but not significantly (p>0.05) different. Water quality parameters were significantly (p<0.05) different between specific treatments. A total of 25 genera of plankton were recorded during the study period. The study indicated that the high density of mola exerts a negative impact on the production of rohu and mrigal. Based on the total production and profit, T₁ was found to be the best.