Studies on production of carps under polyculture system in farmers' ponds

Abstract

The experiment was made to determine the effects of various inputs viz;
organic manure (X), inorganic fertilizers (X2), supplementary feed (X), lime
(X4) and pond size (X5
) on fish yield (Y). A simple correlation coefficient (r)
was found out between yield (Y) and each of the five independent variables
(Xl to X5) under treatments Tl and T2. The first treatment (Tl) consisted of
supplementary feed (100% rice bran) and second treatment (T2) consisted of
supplementary feed (25% mustard oil cake plus 75% rice bran). The results
of the coefficient correlation were X3 (rl = 0.99, r2 = 0.99), Xl (rl = 0.93, r2 = 0.91) and X2 (rl = 0.76, r2 = 0.75), and showed highly positive correlation
(P < 0.01) with fish yield. Pond size (X5
) showed positive correlation (P<0.05)
with fish yield in case of Tl but it showed insignificant effect in T2
. Lime (X4
)
showed negative correlation with fish yield. Among the inputs supplementary
feed, organic manure and inorganic fertilizers had significant effect on fish
yield in farmers' ponds. The average fish yield obtained was 1,640 and 2,795
kglha17 months under the treatments Tl and T2 respectively. Analysis of
variance showed significant difference (P<0.05) in fish yield under both the
treatments and among the replications. Economic analysis revealed a net
profit of 52,015 and 87,621 Tklha/7 months in treatments Tl and T2
respectively. The predicted average yield equation are also presented in this
paper