LABORATORY BIOASSAY FOR INVESTIGATING THE REPELLENT AND OVIPOSITION-DETERRENT IMPACTS OF VARIOUS IGRS ON GUAVA FRUIT FLY, BACTROCERA CORRECTA (DIPTERA: TEPHRITIDAE)

A laboratory bioassay was carried out to assess the repellent impacts of various igrs on guava fruit fly, bactrocera correcta (diptera: tephritidae). the results reveal that settling response of adult guava fruit fly, percent repellency and percent oviposition-deterrence to treated fruit increased with increasing concentration of all evaluated igrs. less number of adult fruit flies settled on fruits treated with silent® [12 (60%)] followed by sitara® [13(65%)], admiral® [13(65%)] and runner® [13.7(69%)] at their highest concentration used in present study. repellency test revealed that silent® explained comparatively maximum repellency (22.3%) followed by admiral® (19.7%), sitara® (19%) and runner® (18%) at their highest concentration used in present study. probit analysis also demonstrated that silent® proved highly effective repellent for adult guava fruit flies as it revealed the minimum rc_50 value (0.61%) followed by admiral®, sitara® and runner® which exhibited 0.86, 0.97 and 1.06% rc_50 values, respectively. similarly, silent® proved highly effective oviposition- deterrent for adult guava fruit flies as it revealed the minimum odc_50 value (0.59%) followed by admiral®, sitara® and runner® which exhibited 0.6, 0.66 and 1.2% odc_50 values, respectively. however, a comparison of frd with rc_50 and odc_50 values of igrs expounded that none of the evaluated igrs would be effective repellent or oviposition-deterrent because rc_50 and odc_50 values of silent®, admiral®, sitara® and runner® were many times higher than their frd. in conclusion, these igrs can be used as repellent or oviposition-deterrent for fruit flies at higher dose rates; but it would be better to apply these igrs for impregnation in impregnated-bagging-technique than foliar application.