Optimizing light trap height and installation timing for effective monitoring of insect pests in rice field

The use of chemical pesticides in the agriculture are widely used but have harmful environmental and health impacts. However, it is hazardous to human health with the environment and is often used more than the prescribed amount. The solar light trap is a popular renewable and environment-friendly device. Although light traps are effective, their ideal height and deployment timing in rice fields remain not clear. This study was undertaken with a specific objective of selecting the appropriate installation height, and lighting time period of the solar light trap where LED bulbs were used in capturing insect pests and beneficial insects in rice fields in BRRI regional station Rajshahi, Bangladesh. The findings demonstrated significant variations in pest capture efficiency across different lighting durations. Early-night trapping recorded the highest captures of green leafhoppers (96.67 individuals) and rice bugs (39.67 individuals), while late-night trapping was most effective for stem borers (577.00 individuals) and rice leaf folders (35.33 individuals). The height of trap installation also influenced pest captures, with canopy-level traps (1.0 m) proving most effective for pests such as green leafhoppers and caseworms. Beneficial insects, including carabid beetles and earwigs, similarly exhibited a preference for traps set at higher positions. These results underscore the significance of optimizing operational parameters for light traps to improve their effectiveness in pest management. By minimizing dependence on chemical pesticides, the use of canopy-level (1.0 m) light traps supports sustainable rice cultivation and provides valuable guidance for integrating them into IPM programs tailored to specific agro-ecological conditions.