A STUDY ON LIGHT TRAP CATCHES OF SOME RICE PESTS IN RELATION TO METEOROLOGICAL FACTORS

Abstract

The effect of meteorological factors on the population build up of green leafhopper Nephotettix virescens Dist (Cicadellidae, Hemiptera), plant hoppers Cofana spectra Dist (Delphacidae, Hemiptera) and C. yasumatsui Young (Kolla mimica, Hemiptera) and rice gundhi bug Leptocoriza acuta Thunberg (Alydidae, Hemiptera) in rice growing season (July to November) was studied through light trap collection during ten years (1988–1997). Maximum populations of Nephotettix virescens Dist (Cicadellidae, Hemiptera) and C. yasumatsui Young (Kolla mimica, Hemiptera) were recorded in the third week of October during all the years. Cofana spectra Dist had maintained peak activity in respect of population in the last week of September and third week of October. Leptocoriza acuta Thunberg (Alydidae, Hemiptera) had maximum population in second and third weeks of October during the aforesaid period. No meteorological factors have significant effect on the population build up of Nephotettix virescens Dist, Cofana spectra Dist and C. yasumatsui Young in the month of October. In the case of Leptocoriza acuta Thunberg, no other factor but rainfall had positive correlation of order 0.857 with population build up in the fourth week of September.