Bioefficacy of Cleistanthus collinus extracts in different solvents against rice stem borer

Bioefficacy of Cleistanthus collinus leaf extracts, prepared using different solvents, were tested against stem borers in rice under field conditions. Eight treatments, including fresh leaf extract, leaf decoction, and extracts in organic solvents like carbon tetrachloride, methanol, chloroform, ether, and acetone, were evaluated along with an untreated control. The botanical formulations were applied as 5% foliar sprays when infestation reached the economic threshold level. Among all treatments, methanol leaf extract exhibited the highest efficacy, significantly reducing stem borer infestation by 72.83 and 71.68% over control in the two respective trials. Other solvent extracts also showed notable effectiveness as compared to the control.