Mitotic and polytene chromosome analyses in the Queensland fruit fly,Bactrocera tryoni(Diptera: Tephritidae)

Abstract

The Queensland fruit fly, Bactrocera tryoni, like the Mediterranean fruit fly, Ceratitis capitata, has a diploid complement of 12 chromosomes, including five pairs of autosomes and a XX/XY sex chromosome pair. Characteristic features of each chromosome are described. Chromosomal homology between B. tryoni and C. capitata has been determined by comparing chromosome banding pattern and in situ hybridisation of cloned genes to polytene chromosomes. Although the evidence indicates that a number of chromosomal inversions have occurred since the separation of the two species, synteny of the chromosomes appears to have been maintained.

Cytogenetic analysis of the Ethiopian fruit fly Dacus ciliatus (Diptera: Tephritidae)

“…The arms of each individual chromosome are unequal in length, corresponding to the submetracentric mitotic arms. No banded sex chromosomes were identified in the polytene complement of D. ciliatus, consistent with previous reports on C. capitata (Bedo 1986(Bedo , 1987Zacharopoulou 1987Zacharopoulou , 1990, B. oleae (Mavragani-Tsipidou et al 1992;Zambetaki et al 1995), B. tryoni (Zhao et al 1998), B. cucurbitae (Shahjahan and Yesmin 2002), B. dorsalis (Zacharopoulou et al 2011), R. cerasi (Kounatidis et al 2008) and R. completa (Drosopoulou et al 2010) and on the califorids, Lucilia cuprina (Childress 1969;Foster et al 1980;Bedo 1982) and Chrysomya bezziana (Bedo 1992). The heterochromatic network found in all polytene nuclei of D. ciliatus individuals (Fig.…”

“…1). Consistent with most tephritid species analyzed so far (Bush 1962;Bhatnagar et al 1980;Singh and Gupta 1984;Bedo 1986;Solferini and Morgante 1987;Zacharopoulou 1987Zacharopoulou , 1990Mavragani-Tsipidou et al 1992;Baimai et al 1995Baimai et al , 1999Baimai et al , 2000Selivon and Perondini 1997;Zhao et al 1998;Shahjahan and Yesmin 2002;Cevallos and Nation 2004;Selivon et al 2005;Kounatidis et al 2008;Cáceres et al 2009;Garcia-Martinez et al 2009;Drosopoulou et al 2010;Zacharopoulou et al 2011), the heterogametic karyotype (XY) of D. ciliatus was ascribed to the male. However, this is a subject of further investigation and confirmation since female heterogamety was detected in some tephritids (Frias 1992;Davies and Roderick 2005).…”

“…As in several other studies on tephritids (Foster et al 1980;Bedo 1986;Zacharopoulou 1987Zacharopoulou , 1990MavraganiTsipidou et al 1992;Zhao et al 1998;Shahjahan and Yesmin 2002;Kounatidis et al 2008;Drosopoulou et al 2010;Zacharopoulou et al 2011), no typical chromocenter like that of Drosophila melanogaster exists in the D. ciliatus polytene complement. Each individual polytene chromosome is easily identified by the different size and appearance of its heterochromatic centromeric mass (Fig.…”

“…2a-e). Characteristic centromeric masses, which are identifying landmarks of each polytene chromosome, have been found in other Diptera as well (Mavragani-Tsipidou et al 1992;Zhao et al 1998;Kounatidis et al 2008;Drosopoulou et al 2010;Zacharopoulou et al 2011). The observed differences in size, density and appearance of these structures might reflect differences in the amount of pericentromeric heterochromatin.…”

“…1). C. capitata (Bedo 1986;Zacharopoulou 1987), and many species of the genera Bactrocera (Bhatnagar et al 1980;Singh and Gupta 1984;Mavragani-Tsipidou et al 1992;Hunwattanakul and Baimai 1994;Baimai et al 1995Baimai et al , 2000Zhao et al 1998;Shahjahan and Yesmin 2002), Anastrepha (Selivon and Perondini 1997;Cevallos and Nation 2004;Selivon et al 2005;Garcia-Martinez et al 2009) and Rhagoletis (Bush and Boller 1977;Frias 2002;Kounatidis et al 2008;Drosopoulou et al 2010) all show the same number of mitotic chromosomes. However, a different number of mitotic chromosomes has been reported in some tephritids (Bush and Boller 1977;Morgante 1987, 1990).…”