Growth, Development and reproduction of fruit fly, Bactrocera dorsalis Hendel (Diptera : Tephritidae) on different Mango cultivars, viz. Dashehari, Langra, Chausa and Amrapali

Abstract

India is the largest producer and exporter of mangoes. It produces choicest cultivars in different region of the countries. However, its export is hampered by susceptibility to fruit fly Bactrocera dorsalis Hendel, as the importing counties are wary of introduction of Indian strain of B. dorsalis into their counties. Consequently, they have imposed many pre export requirements viz., hot water treatment, vapour heat treatment, irradiation, etc. The present study attempts to study growth, development and reproductive cycle of fruit fly, Bactrocera dorsalis, Hendel on four mango cultivars, viz. Chausa, Langra, Dashehari and Amrapali. The development of the immature stages of B. dorsalis was found to differ, when they were reared on four mango cultivars. The incubation period of eggs of B. dorsalis was minimum (1.75 ± 0.11 days) on Chausa cultivar and maximum (3.30 ± 0.13 days) on Amrapali cultivar. Duration of first larval instars was fastest (1.85 ± 0.13 days) on Chausa and slowest (3.55 ± 0.16 days) on Amrapali. The developmental of second larval instars of B. dorsalis varied from 2.25 ± 0.11 to 4.00 ± 0.15 days with the minimum period on Chausa and maximum on Amrapali (F= 35.12; P<0.001). The third larval instar developed fastest (4.45 ± 0.69 days) on Chausa and slowest (7.60 ± 0.22 days) on Amrapali (F=17.53; P< 0.001). The total developmental period of immature stages of B. dorsalis was shortest (19.45 ± 0.68 days) when fed on Chausa and longest (30.65 ± 0.33 days) when fed on Amrapali (F=93.57; P<0.001). The fastest development took place on Chausa cultivar and slowest on Amrapali. The different reproductive parameters of B. dorsalis varied significantly when fed on four different mango cultivars. Fecundity of B. dorsalis on mango cultivar varied from 189.80 ± 1.44 to 561.20 ± 3.21 eggs with the least on Amrapali and highest on Chausa (F= 7288.07; P<0.001). The percent egg viability was least (73.22 ± 1.02 %) when adults were reared on Amrapali cultivar and highest (82.50 ± 0.39%) on Chausa cultivar (F=20.00; P <0.001).