The Effect of Organic Media in Compensating for Nutrient Deficiency in the Growth of Bell Peppers

Organic substrate can increase crop productivity. This experiment aimed to improve the yield and growth parameters of sweet pepper (Capsicum annuum L. cv. ‘Gold flame’) by using three levels of modified Johnson’s nutrient solution (JNS), including full JNS as the control (NSc), 75% JNS (NS1) and 50% JNS (NS2) as well as three types of substrates that were based on three levels of vermicompost: vermicompost:perlite:cocopeat (1:1:1 v/v; V1) as the control, vermicompost:perlite:cocopeat (1:1:2 v/v; V2) and vermicompost:perlite:cocopeat (2:1:1 v/v; V3). Fruit fresh weight (86.18%) and dry weight (43.03%), root dry weight (68.63%) and root volume (43.67%), fruit diameter (12.39%) and yield (59.30%) increased significantly in V3 treatment. The application of vermicompost increased photosynthesis rate, respiration, nitrogen, phosphorus, and potassium concentrations more than Johnson’s nutrient solution. Fruit fresh and dry weights, root fresh and dry weights, root volume, fruit diameter and yield decreased in NS2 and NS1 and application of V3 improves the fresh weight of fruit in NS1. The highest fruit yield was observed in NSc treatment in combination with V3. Photosynthetic rate, and P and K concentrations increased with vermicompost application in all nutrient solution. The N and P concentrations decreased in NS1 and NS2 while respiration was stimulated by V2 and V3 in combination with NS1. The P decreased in NS1 and NS2 but was stimulated by both V2 and V3 treatments. The N level was reduced in NS1 and NS2 but V3 enhanced the level of N when combined with NS1. Overall, plant growth, yield, photosynthesis and nutrient N, P, K concentrations can be increased in sweet pepper by the addition of vermicompost and nutrient solution.