Impact of periphyton on makhana (<i>Euryale ferox</i> Salisbury) cum fish culture: a study in North Bihar, India

Bihar possesses rich aquatic biodiversity and abundant water resources. Furthermore, the commercial aquatic crop industry in the northern region of Bihar often employs co-cultivation practices. The study was conducted at the ICAR-National Research Centre for Makhana in Darbhanga, Bihar. The objectives of the study were to investigate the impact of periphyton-based aquaculture on the makhana cum fish culture system, the compatibility of Indian major carp (IMC), and assess water quality parameters. The experiment, from December 2021 to November 2022, utilized the ‘ Swarna Vaidehi ’ makhana variety and Indian major carp. The study was conducted in a pond having an area of 800 m 2 with a depth of 1.2 to 1.5 m in triplicates, applying six treatments (MF1 to MF6), including periphyton substrate frame, fertilization, and supplementary feed. Fish fingerlings of various species were stocked during the investigation at the rate of 6000 individuals per hectare in makhana-fish integrated ponds. The stocked species included catla ( Catla catla ), rohu ( Labeo rohita ), and mrigal ( Cirrhinus mrigala ) in a ratio of 2:2:1, respectively. Results indicated significant influences of treatments on fish and makhana yields. Treatment MF4 yielded the highest total fish production, including catla, rohu, and mrigal, with values of 0.98 ± 0.006, 0.98 ± 0.004, and 0.092 ± 0.005 t ha −1 yr −1 , respectively, while treatment MF5 led to makhana seed production at 1.78 ± 0.077 t ha −1 yr −1 . The estimated yield in the experiment differed significantly among the treatments, as determined by the ANOVA. Moreover, incorporating periphyton substrate frames improved water quality and natural food availability, enhancing fish production without compromising makhana seed yield. Thus, a periphyton-based makhana cum fish farming system holds the potential to enhance productivity and could be a sustainable farming technique in the northern part of Bihar and elsewhere in India with similar conditions.