Seasonal monitoring of two Bactrocera Species using methyl eugenol traps on guava orchards in Hyderabad district

Abstract

An experiment was performed during consecutive three years (2011-2014) on the seasonal monitoring of fruit flies (B. zonata and B. dorsalis) using methyl eugenol traps at different heights in guava orchards. The pheromone traps baited with lure toxicant mixture (95% methyl eugenol + Thiodan insecticide) were installed at surface (T1), 1 m (T2), 2m height (T3) and 3 m (T4). The effect of different heights of methyl eugenol pheromone traps on the male-adult B. zonata and B. dorsalis catches was statistically significant (P<0.05); and the fruit fly catches in traps varied significantly during 12 months of the year (P<0.05). The pest catches differed significantly (P<0.05) during the years of study (2011-2014); while the interactive effect of years and treatments were non-significant (P>0.05). The highest B. zonata catches (1428.4±260.04) were monitored in traps installed at 2m height; while the monthly B. zonata trap catches simultaneously decreased to 1340.5±230.02, 1185.4±202.56 and 1177.3±210.23 at trap heights of 0 m (surface), 1 m and 3 m, respectively. The average monthly trap catches of B. zonata were 1282.90±287.55. The maximum monthly B. dorsalis catches (7.34±0.70) were found in traps installed at 2m height; while the monthly B. dorsalis trap catches decreased to 6.29±0.60, 4.96±0.49 and 4.67±0.48 when the traps were installed at 0 m (surface), 1 m and 3 m heights, respectively. The average monthly trap catches of B. dorsalis were 5.81±0.55. It was concluded that the methyl eugenol pheromone traps were most effective when installed at 2 m height; while traps installed at 1 m and 3 m height could not catch B. zonata and B. dorsalis more than the surface installed traps. The B. zonata starts its rapid development from the month of May and sustains upto the month of September with certain fluctuation.