Comparative analysis of development and survival of two Natal fruit fly Ceratitis rosa Karsch (Diptera, Tephritidae) populations from Kenya and South Africa.

Sunday Ekesi,Aruna Manrakhan,John-Henry Daneel,Khamis Fathiya,Samira A Mohamed,Chrysantus M Tanga

doi:10.3897/zookeys.540.9906

Abstract

Comparative analysis of development and survivorship of two geographically divergent populations of the Natal fruit fly Ceratitis rosa Karsch designated as Ceratitis rosa R1 and Ceratitis rosa R2 from Kenya and South Africa were studied at seven constant temperatures (10, 15, 20, 25, 30, 33, 35 °C). Temperature range for development and survival of both populations was 15–35 °C. The developmental duration was found to significantly decrease with increasing temperature for Ceratitis rosa R1 and Ceratitis rosa R2 from both countries. Survivorship of all the immature stages of Ceratitis rosa R1 and Ceratitis rosa R2 from Kenya was highest over the range of 20–30 °C (87–95%) and lowest at 15 and 35 °C (61–76%). Survivorship of larvae of Ceratitis rosa R1 and Ceratitis rosa R2 from South Africa was lowest at 35 °C (22%) and 33 °C (0.33%), respectively. Results from temperature summation models showed that Ceratitis rosa R2 (egg, larva and pupa) from both countries were better adapted to low temperatures than R1, based on lower developmental threshold. Minimum larval temperature threshold for Kenyan populations were 11.27 °C and 6.34 °C (R1 and R2, respectively) compared to 8.99 °C and 7.74 °C (R1 and R2, respectively) for the South African populations. Total degree-day (DD) accumulation for the Kenyan populations were estimated at 302.75 (Ceratitis rosa R1) and 413.53 (Ceratitis rosa R2) compared to 287.35 (Ceratitis rosa R1) and 344.3 (Ceratitis rosa R2) for the South African populations. These results demonstrate that Ceratitis rosa R1 and Ceratitis rosa R2 from both countries were physiologically distinct in their response to different temperature regimes and support the existence of two genetically distinct populations of Ceratitis rosa. It also suggests the need for taxonomic revision of Ceratitis rosa, however, additional information on morphological characterization of Ceratitis rosa R1 and Ceratitis rosa R2 is needed.

Highlights

Amongst the Afro-tropical group of tephritid fruit flies (Diptera: Tephritidae), Ceratitis rosa Karsch is considered a serious pest of cultivated fruit (White and Elson-Harris 1992, De Meyer 2001a, Copeland et al 2006)
No significant differences in egg developmental duration were observed between the two C. rosa groups at 25 °C (F = 2.075; d.f. = 1, 15; P = 0.1700) and 30 °C (F = 0.946; d.f. = 1, 12; P = 0.3500)
The eggs of both C. rosa groups did not develop at 10 °C

Summary

Introduction

Amongst the Afro-tropical group of tephritid fruit flies (Diptera: Tephritidae), Ceratitis rosa Karsch is considered a serious pest of cultivated fruit (White and Elson-Harris 1992, De Meyer 2001a, Copeland et al 2006). In mainland Africa, C. rosa is known only from southern and eastern Africa, being absent from the western and central parts of the continent (De Meyer 2001a). Outside this native range, C. rosa has been reported from the Indian Ocean islands of Mauritius and La Réunion where it is regarded as a major pest of quarantine importance (Orian and Moutia 1960, De Meyer 2001b, White et al 2001, Duyck and Quilici 2002). Reports of C. rosa in different parts of the Western Cape was claimed by some researchers (Hepburn and Bishop 1954)

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