01 Oca 2026 Perşembe
Impact of temperature and age on testis and apodeme development in the melon fly, Zeugodacus cucurbitae
Abstract : Insects are generally semelparous, maturing rapidly and producing a large number of offspring within a short lifespan. During the early stages of life, their reproductive structures undergo notable morphological changes. Among the environmental factors influencing this process, temperature plays a decisive role in shaping both the structural and physiological characteristics of insect reproductive organs. The term gonadal plasticity in insects refers to their ability to modify reproductive organs adaptively in response to environmental cues, thereby optimizing reproductive success under variable conditions. Zeugodacus cucurbitae (melon fly) is a serious agricultural pest that infests hundreds of vegetable crops of economic importance. Its global distribution is attributed to its remarkable adaptability to changing environments. In the present study, we investigated two genetically distinct strains of Z. cucurbitae reared under three different temperature regimes (18 °C, 26 °C, and 34 °C) to examine age-related changes in the testes and apodeme of males across four developmental age groups. The findings revealed that the testes in both strains attained maximum size at the laboratory temperature of 26 °C, whereas, their size was significantly reduced under elevated temperature conditions across all age groups. In contrast, the apodeme showed progressive enlargement with advancing age at 26 °C, exhibited no prominent variation at 18 °C, and displayed a marked reduction at 34 °C. These results highlight the pronounced influence of temperature as an abiotic factor on the development of the testes and apodeme in Z. cucurbitae.