Vol. 9, Issue 11, Part E (2025)

Experiment was conducted to find out the relative toxicity of chitin synthesis inhibitors viz., lufenuron and novaluron with 25, 50 and 75 ppm concentration against third instar larvae of Spodoptera frugiperda (J. E. Smith) under laboratory conditions at College of Agriculture, Kolhapur, (Maharashtra) during summer 2024-25. 
Among chitin synthesis inhibitors with three different concentrations tested for their larvicidal action revealed that Novaluron @ 75 ppm was found most effective and superior, it was followed by Novaluron @ 50 ppm. The percent mortality recorded at 6, 24, 48 and 72 hours after treatment. There was no mortality found 6 hours after treatment. After 24 hours, mortality ranged between 17.78 to 28.89 percent. After 48 hours, mortality increased considerably and ranged between 41.11 to 68.89 percent. At 72 hours after treatment, all the treatments showed its maximum efficacy and recorded Percent mortality of novaluron @ 25, 50 and 75 ppm were 86.67, 92.22 and 97.78; While, Percent mortality of lufenuron @ 25, 50 and 75 ppm were 77.78%, 84.33% and 88.67% respectively.