The development of an organic nutrient solution for baby cos lettuce (Lactuca sativa L.) production in a hydroponic system

Abstract

In the production of lettuce using an organic hydroponic system, the development of an appropriate nutrient solution is crucial for optimal plant growth. This study aimed to evaluate the effectiveness of organic nutrient solutions on growth and yield of baby cos lettuce. A completely randomized design (CRD) with five replications was used. Six treatments were applied: the modified Hoagland solution (control; Tr1), organic nutrient solution 1 (compost 1; Tr2), organic nutrient solution 2 (compost 2; Tr3), organic nutrient solution 3 (vermicompost; Tr4), organic nutrient solution 4 (compost 1 and vermicompost (1:1); Tr5) and organic nutrient solution 5 (compost 2 and vermicompost (1:1); Tr6). Lettuce seeds were germinated and the seedlings were subsequently transplanted into a hydroponic system. At harvest, data were collected on leaf greenness, leaf color, leaf number, biomass, nitrate content, and the presence of Escherichia coli (E. coli). The results demonstrated that the different nutrient solution formulations had significant effects on plant growth parameters, photosynthetic efficiency, leaf greenness, leaf color, yield, and nitrate accumulation. Organic nutrient solution 1 (Tr2) and organic nutrient solution 2 (Tr3) yielded the highest fresh weights, indicating their superior performance. Nitrate concentrations in organic nutrient solutions ranged from 1,235 to 3,825 mg kg^-1 and E. coli was not detected in any treatment.