Evaluation of Soil Solarization for Controlling Root-knot Nematodes on Tropical Peppers in Open-fields

Chili peppers cultivated in open-fields in Hainan province are commonly infested by root-knot nematodes (RKN). This study focused on the effect of disinfection by using solar energy to control the pepper RKN disease. Transparent plastic mulch film was used to cover the soil for evaluation. The highest temperatures of the solarized soil layers at 5 cm, 10 cm, 15 cm and 20 cm were found to be 73℃, 57.8℃, 45.1℃ and 43.9℃, respectively. After 30-60d mulching, the population of the second-stage RKN juveniles was reduced by 54.8%-57.5%. Two months after the plants were transplanted, the control efficacy was 65.9%-70.3% and remained at 55.9%-59.1% level 5 months after the transplantation. Duration of mulching did not show any significant difference on the efficacy. The abundant sunshine in Hainan would render the solarization a method feasible and cost effective for controlling RKN while minimizing the dependency on chemical nematicides.