DATE PALM FRUITS AS A POTENTIAL HOST OF THE PEACH AND MEDITERRANEAN FRUIT FLIES IN FAYOUM GOVERNORATE

Abstract

The peach fruit fly, Bactrocera zonata (Saunders) and the Mediterranean fruit fly Ceratitis capitata (Wiedmann) are two of the most destructive fruit flies that attack commercial fruits causing significant damages. This study was contributed for monitoring the relative abundance and infestation percentage of B. zonata and C. capitata during two successive seasons, 2010 and 2011 in Fayoum governorate. The experimental locations included various types of date palm cultivation including, firstly, the mixed fruit orchards that containing mango and citrus beside date palm trees, secondly, the orchards containing field crop and vegetables bedside fruit and date palm trees, thirdly, an aggregated date palm orchards only. During The 1st season, the means of CTD (captured flies per trap per day) of B. zonata were 7.68 , 4.55,and 1.65 flies, for the forementioned types, respectively, while during the 2nd season, the means of CTD were 15.31, 6.55 and 0.47 flies for the same cultivations, respectively. The highest CTD values of B. zonata were 11.95 and 26.71 flies / trap/ day observing on 3rd week of October and 3rd week of September during the two seasons, 2010 and 2011, respectively, recorded on the mixed orchard cultivations. Population of C. capitata was low in mixed-cultivation orchards, whereas the means of CTD were 0.16 and 0.48 fly during the 1st and 2nd seasons, respectively, while, there weren't captured flies of C. capitata on the other two types of mentioned date palm cultivations.The samples of fallen date fruit were free of infestation by either of B. zonata or C. capitata in the mature stage for the four tested varieties (Siwi, Amhat, Zaghloul and Balady) of date palm. Percentages of infestation of B. zonata in the fallen palm fruits for the half-ripe and ripe stages during the 1st season in Siwi, Amhat, Zaghloul and Balady varieties were 18.29, 6.31, 6.36, 4.37, 16.29, 5.50 and 20.51, 5.66%, respectively, and during the 2nd season, the percentages of infestation were 34.40, 17.00, 9.42, 3.10, 25.00, 11.76 and 28.96, 6.15%. The obtained data suggests that the earlier control of the fly on the former crop, removal of the infested date fruits that are shelter of immature stages of B. zonata and C. capitata, also, the early harvesting of some date varieties that could be marketing on mature stage results in reducing the population and percentages of infestation of the two flies. Also, avoidance of mixed fruit host cultivation and removing the secondary hosts support such procedures.