valuation of a nutrient film aquaponic system for growing of lettuce

Abstract

Aquaponics as a key factor in the advancement of integrated food production systems and noted potential by simultaneous combination of aquaculture and hydroponics practice. This study evaluate a nutrient film aquaponics system (NFT) for catfish and lettuce. The catfish was raised under different feeding rate treatment: 5% (TRT5%) and 3% (TRT3%). The lettuce was grown with the water from the two treatments and the convectional method (control). The observation were taken in seventh days after transplanting for 4 weeks. The effect of the treatments and water quality on the growth and yield parameters of lettuce were analyzed using analysis of variance and regression analysis at 5% significance level. The result shows that the initial weight of the stocked fish under different treatment tanks had no significant difference (P<0.05). In 3-10th weeks, TRT5% is significantly (P<0.05) higher than the TRT3%. The TRT5% significantly increased the leaf number and plant height of the lettuce by 27.38% and 28.72% respectively con. The TRT3% significantly increased the leaf number and plant height of the lettuce by 13.10% and 12.34% respectively. The developed mathematical models for number of leaf, plant height, leaf area, weight and productivity had an accuracy of93.2%, 95.6%, 99.7%, 98.28% and 83.32% respectively, Therefore, it should be adopted by small and medium scale aquaponics farmer for significant prediction on lettuce yield as a function of NFT water quality.