Effect of Flow Rate and Length of Gully on Lettuce Plants in Aquaponic and Hydroponic Systems

Abstract

The main objective of this research is to study the effect of source of nutrients, water flow rate and length of gully to know the possibility of producing lettuce plants depending on the nutrients existing in effluent fish farm as compared with the lettuce production using standard nutrient solutions. To achieve that was studied the effect of source of nutrients (effluent fish water and nutrient solution), flow rate (1.0, 1.5 and 2.0 L min-1 ) and length of gully (2, 3 and 4 m) on the following parameters: nutrient uptake, dry weight and NO3 -N content in plant. The obtained results indicated that the fresh and dry weight of shoots increased in nutrient solution over those of effluent fish farm. The fresh and dry weight of shoots decreased with increasing the flow rate and the length of gully. The dry weight of roots increased in nutrient solution over those of effluent fish farm. The dry weight of roots decreased with increasing the flow rate and the length of gully. The NO3 -N content significantly increased in nutrient solution over those of effluent fish farm. The NO3 -N content decreased with increasing the flow rate and length of gully. The NO3 /protein ratio increased in nutrient solution over those of effluent fish farm.