Crop loss estimation due to capsule borer Helicoverpa armigera (Hubner) in safflower

Abstract

Safflower yield loss assessment due to the capsule borer Helicoverpa armigera (Hubner) on plants in field conditions. The H. armigera density had a significant effect on number of seeds per capsule, 100 seed weight, yield per plant and recorded minimum in 10 larvae per plant (8.40, 2.50g and 2.53g respectively) and maximum in control plot (36.66, 6.82g and 13.46g respectively) followed by completely protected (spray) treatment and natural population (No cage) treatment and these three were on par with each other. The economic injury level of H. armigera was worked out to be 0.53 larvae per plant for A-1 variety of safflower. This means chemical control measures are to be imposed before H. armigera population reaching 5.3 larvae per 10 plants so as to realize a profitable safflower crop production.