The effect of rice hull as a silicon source on anthracnose disease resistance and some growth and fruit parameters of capsicum grown in simplified hydroponics

Introduction Silicon is beneficial for many plants forgrowth, yield and enhancing resistance to biotic and abioticstresses. In the present study, silicon as a form of rice hullsand mixture (3:2 v/v) was used in simplified hydroponicsystem to evaluate the performance and disease resistanceof Capsicum annuum L. The nutrients were supplied by NF(New Formula) or Albert’s solution.Results Continuous monitoring of soluble silicon contentin the simplified hydroponic boxes revealed that a highamount of silicon was leached by the rice hull sand medium.Disease resistance was assessed by challenge inoculationof harvested fruits with anthracnose-causing fungi,Colletotrichum gloeosporioides, and it was observed asignificant disease reduction (over 83 %) in fruits harvestedfrom simplified hydroponic system compared to that ofliquid hydroponic system. Shoot length, root length, fruitlength, fruit weight and fruit firmness were also increasedsignificantly in simplified system compared to the liquidsystem. However, the results were not significantly affectedby the nutrient solutions used in these two systems.Conclusions In conclusion, the simplified hydroponicsystem composed of rice hull, as a natural silicon supplementcould be used as a low-cost environmental friendlygrowing method of capsicum to enhance resistance againstanthracnose disease, and to improve plant growth and fruitquality.