Investigations on the population dynamics of fruit flies in mango orchard at Dharwad.
Ranjitha A. R., Shashidhar Viraktamath
Author Affiliation: Department of Agricultural Entomology, College of Agriculture, Dharwad - 580 005, India.
Karnataka Journal of Agricultural Sciences 19 : 134-137
Abstract : The population dynamics of fruit flies in a mango orchard in Dharwad, Karnataka, India, was studied from July 2003 to April 2004. Three species of fruit flies, i.e. Bactrocera dorsalis, B. correcta and B. zonata, were recorded. In 2003, the B. dorsalis population peaked on the 30th standard week (22.47 flies), then declined thereafter. In 2004, the B. dorsalis population remained low (up to 2.17, 2.52 and 5.04 flies on the 4th, 12th and 13th standard weeks, respectively). In 2003, the population of B. correcta reached 92.82 flies on the 27th standard week, declined and remained low until the 38th week, then increased rapidly on the 39th standard week, recording a major peak (341.53 flies) on the 45th standard week. Smaller peaks were recorded during the 52nd standard week (153.93 flies) in 2003 and on the 3rd standard week (133.42 flies) in 2004. The B. zonata population peaked on the 30th (8.68 flies), 42nd (16.80 flies), 45th (14.42 flies), 4th (9.94 flies), 8th (18.48 flies) and 13th (16.24 flies) standard weeks. With regard to the total number of fruit flies, peak catches were recorded on the 30th (120.89 flies), 43rd (280.28 flies), 45th (361.69 flies) and 52nd (158.41 flies) standard weeks in 2003, and on the 3rd (135.38 flies) and 8th (70.84 flies) standard weeks in 2004. The B. dorsalis population was positively correlated with minimum temperature, and morning and afternoon relative humidities, but negatively correlated with maximum temperature. The B. correcta population was negatively correlated with minimum temperature. The B. zonata population was positively correlated with maximum temperature.