PATEL, Z.P.BANSODE, GANESH M.2016-03-102016-03-102009-06http://krishikosh.egranth.ac.in/handle/1/65033Investigations on the comparative biology, population dynamics and management of orchard flies (Bactrocera spp.) were carried out during 2004-2005 and 2005-06 at Navsari Agricultural University, Navsari. Studies on comparative biology of B. dorsalis on various hosts revealed that the female laid eggs in small clusters just underneath the rind of fruit, 2-4 mm. deep in the epidermis. Freshly laid eggs were shiny, translucent and whitish coloured. The shape of egg was cylindrical, slightly curved on one side and narrow at both ends. The length and breadth of eggs was varied from 0.8 to 1.07 and 0.14 to 0.25 mm on different hos ts. During the studies, lower incubation period of B. dorsal is was recorded in mango (2.68 ± 0.60 days) followed by that sapota (2.76 ± 0.83 days), guava (3.00 ± 0.71 days) and banana (3.12 ± 0.67 days). The difference in hatching percentage of eggs laid in various fruits was not observed markedly during the investigation. The larva completed its larval period earlier when fed on mango (7.44 ± 1.66 days) compared to guava (7.84 ± 1.03 days), banana (8.52 ± 0.71 days) and sapota (9.40 ± 1.47 days). The pre-pupal period did not differed (0.5 to 1 day) when B. dorsalis was reared on different hosts. The pupation of B. dorsalis took place at depth of 0.5 to 5.0 cm in soil. The longer pupal period was recorded on sapota (7.80 ± 0.82 days) compared to guava (7.20 ± 0.76 days), banana (7.20 ± 0.82 days) and mango (7.00 ± 0.71 days). The average pre-oviposition period was recorded as 9.20 ± 1.41 days on sapota, 8.80 ± 1.08 days on banana, 8.32 ± 1.11 days on guava and 8.16 ± 1.18 days on mango. The average oviposition period was recorded as 6.12 ± 1.44 days on mango, 5.96 ± 1.65 days on guava, 5.52 ± 1.50 days on banana and 5.48 ± 1.45 days on sapota. Similarly, the post-oviposition period was recorded as 3.40 ± 0.82 days on sapota, 3.04 ± 0.84 days on banana, 3.00 ± 0.76 days on guava and 2.88 ± 0.78 days on mango. The measurements of each stage of B. dorsalis on different hosts were also discussed. The maximum numbers (180.00 ± 35.76) of eggs were laid on mango fruits compared to rest of the fruits. Studies on longevity of adults indicated that the female fly lived longer (13 to 24 days) than male fly (7 to 14 days). The total life cycle of male was shorter (24.50 to 36.50 days) than the female (30.00 to 46.00 days) irrespective of host f ruit. The total life cycle was completed in 24.50 to 46.50 days on different hosts, however, i t was shorter on mango than rest of the frui ts. Thus, the studies on comparative biology indicated that mango was the most suitable fruit for faster development of B. dorsalis. Studies on population dynamics of fruit fly indicated that the f ruit fly population prevailed throughout the year in mango, guava and sapota orchard. However, its maximum activity was found during March to August on sapota, April to July on mango, August to September on banana and June to November on guava. The correlation and multiple regression studies between frui t fly population and weather parameters were also worked out and discussed. Studies on population dynamics of f ruit fly based on per cent infestation indicated that the maximum fruit fly infestation was observed from April to August on sapota, May to July on mango, in August on banana and August to October on guava. The infestation also coincided with harvesting period of respective fruit. The studies on species composition revealed the prevalence of three species of fruit flies in south Gujarat. Among them, B. zonata was found as most dominant (62.05 per cent) species of fruit fly followed by B. dorsalis (37.27 per cent) and B. correcta (< 1 per cent). Studies on effect of different traps indicated that the D.F.I.D (Department for International Development) water bottle trap caught significantly higher male flies than the modified (Patel) and conventional fruit fly trap. Further studies on efficacy of D.F.I.D water bottle trap indicated that the D.F. I. D water bottle trap (5x5x1.2cm.) remained more effective up to three months after installation. During the studies on effect of trap height and placement it was found that the traps placed at border at 1.5 m height caught more number of f ruit flies. Studies on marking and recapturing of fruit flies, revealed that the effective range of attraction of frui t flies toward methyl eugenol was from 1 to 3 Km. Installation of traps at many sites is rather impossible during monsoon, which was overcome by designing trap of five times bigger in size than the D.F.I.D block trap during present investigation. Studies on varietal response against fruit fly indicated that the overall infestation in different varieties ranged from 3.33 to 46.47 per cent. Moreover, the late maturing varieties were heavily infested by fruit flies compared to early and mid late varieties. Studies on effect of chemical cons tituents of four mango varieties against fruit fly infestation revealed that the fruit fly infestation had positive correlation with total soluble solids and total sugar; whereas, it had negative correlation wi th phenol. During studies on hot water treatment, it was found that the treatment of 52 oC temperature for 60 min gave higher number of dead and lower number of live maggots than the other treatments. During the studies on area wide control of f ruit flies by male annihilation technique, significantly lowes t fruit infestation was recorded in villages under area wide control treatment than the villages under untreated control . Further studies indicated that the f ruit fly infestation was reduced to 8.33 per cent from 40.33 per cent by adopting area wide control, which tuned to 80 per cent reduction in fruit fly infestation. Studies on awareness about frui t fly among farming community of south Gujarat indicated that the majori ty of farmers of study area had medium level of awareness about fruit fly.enfruits, mangoes, animal developmental stages, biological interaction, guavas, sapota, bananas, eggs, orchards, irrigationThesis