Assessing mating performance of male Glossina pallidipes (Diptera: Glossinidae) using a walk-in field cage

Abstract

To monitor the quality of male tsetse for use in the sterile insect technique (SIT), a field cage test was developed and evaluated. Mating competitiveness was tested with male Glossina pallidipes Austen that emerged from pupae stored for different periods at 15°C. Control males emerged from pupae stored at 23–24°C and emerged at 26.5°C. Each sample of test males was divided into two groups with one group being irradiated at 120 Gy; the other group was not irradiated. More than 70% of the maximum possible number of mating pairs occurred in all tests. Males emerged from pupae kept at low temperature and then irradiated formed a greater proportion of mating pairs than the controls. Males emerged from pupae kept at 15°C generally started mating more quickly than the standard colony males although there was no significant difference. Insemination rates were above 99%. Pooled data indicated that mean spermathecal values for females mated with irradiated males were significantly lower than for control males. The duration of copulation varied significantly between treatment groups and was significantly longer for irradiated male flies; there was no correlation between duration of copulation and mean spermathecal value.

Evaluation of radiation sensitivity and mating performance of Glossina brevipalpis males

“…It was showed that a dose of 120 Gy did not affect mating competitiveness of G . pallidipes males in walk-in field cages and keeping the irradiated pupae for 24–72 h at a low temperature of 15°C even increased the competitiveness of the emerged males [37]. …”

Storage of male Glossina palpalis gambiensis pupae at low temperature: effect on emergence, mating and survival

“…The netting cage [26] was cylindrical, 2.9 m in diameter and 2.0 m high [27,28]. The field cage was erected inside a greenhouse under natural light without environmental controls for the age group experiments.…”

Mating competitiveness of irradiatedGlossina austenitsetse flies

“…In the absence of such interference from a rival, single irradiated males initiated copulation much more quickly. Similar male-male interference has also been observed in more natural, field-cage conditions (Mutika et al 2001).…”

“…An increase in copulation duration can occur in irradiated male potato-tuber moths, and the females may re-mate more quickly after mating with irradiated males (Saour and Makee, 1999). Mutika et al (2001) found that, in general, irradiated male G. pallidipes copulated for longer and transferred fewer sperm than the non-irradiated males. Although the success on Unguja Island indicated that sterilized G. austeni can compete successfully, the effects on irradiation on the mating behaviour of male G. austeni are not well known.…”

“…In a study carried out in field cages, Mutika et al (2001) found that irradiated male G. pallidipes spent longer in copula than untreated males and that the females mated with irradiated males contained fewer sperm than those mated with untreated controls. There was no direct relationship between these two variables (i.e.…”