Seasonal population trend of the peach fruit fly (PFF), Bactrocera zonata (Saunders) (Diptera: Tephritidae), in Assiut, Northern Upper Egypt

Abstract

The population of peach fruit fly during 2011 season increased gradually starting from the fourth week of July to reach its first major peak throughout the second week of September with 1340 flies/trap/day for traps suspended at 1 m height and during the third week of September with 909 flies/trap/day for traps hung at 2 m heights. Afterwards, the population trend showed a slight but gradual declining trend from the third week of September up to the third week of October. The population was then increased to reach its second major peak during the fourth week of October with 696 and 595 flies/trap/day for traps hung at 1 and 2 m heights, respectively. The greatest drop in the trapped population at both trap heights was observed from the second week of November until the end of the season (second week of December). A total of 105270 flies/trap at both 1 and 2 m trap heights during the entire seasons of 2011 were recorded. In 2012 season, the population followed nearly the same trend as that observed during 2011 season with minor variations. One major peak of abundance was recorded during the first week of October with 1344 and 955 flies/trap/day for traps hung at 1 and 2 m, respectively. The second major peak (1104 and 894 flies/trap/day) was observed during the fourth week of October for traps suspended at 1 and 2 m, respectively. A remarkable decrease in the population could be seen from the first week of December until the end of the season (fourth week of December). Statistical analysis of the data showed highly significant differences between fruit fly population captured at 1 m trap height (Mean = 446.9 ± 97 flies/trap/day) and that captured at 2 m trap heights (Mean = 321 ± 72 flies/trap/day) with paired t of 4.7** and p-value of 0.0001**.