UV-C radiation during the pupal stage affects morphological changes of wings in Tribolium castaneum (Col; Tenebrionidae)

Abstract

Purpose: To reveal the effects of Ultraviolet-C (UV-C) on the elytra and hindwing morphology of Tribolium castaneum.

Material and methods: Zero-day-old-pupae were irradiated with UV-C at a distance of 35 cm for 1, 2, 4, 8, 16, 32, or 64 min. Changes in wing morphologies were examined using light and scanning electron microscope.

Results: UV-C radiation decreased the adult emergence rate and the insect body mass. Morphological changes of the elytra and hindwings in the adults were classified into nine grades. The treated insects had wrinkled and split elytra, and hindwings were not folded properly. Radiation altered the size of elytra, hindwings and wing shape. An analysis of the color intensity indicated that the irradiated beetles had darker elytra. The veins of hindwings became darker, while the membranous area had a lighter color than the control. UV-C radiation also affected the thickness of the elytra. Scanning electron microscopy revealed that UV-C caused deformity of elytra surface and decreased the number of hair sensilla.

Conclusions: Results indicate that the elytra and hindwing morphology were altered by UV-C radiation. However, further analysis is required to evaluate the response of T. castaneum to UV-C radiation at the gene level.

Keywords:

• UV-C
• radiation
• red flour beetle
• elytra
• hindwing

Acknowledgments

The authors thank Miss Aunchada Porjai and Miss Nutvara Injai for their technical support. The authors also thank Dr. Pimjai Saengkwamsawang, Department of Physics, School of Science, University of Phayao for measurement the dose of UV-C. This manuscript has been edited by the American Manuscript Editors: project no. #56389 (7/1/2019).

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Research Council of Thailand via the University of Phayao under grant RD61029.

Notes on contributors

Jatuporn Tungjitwitayakul

Jatuporn Tungjitwitayakul is a Lecturer of Biology at the School of Science, University of Phayao, Thailand. She works on topics in insect physiology and insect molecular biology.

Thippawan Yasanga

Thippawan Yasanga is a Researcher of Medical Science Research Equipment Center, Faculty of Medicine, Chiangmai University, Thailand. She works on topics in electron microscopy.

Nujira Tatun

Nujira Tatun is a Lecturer of Biology at the School of Science, University of Phayao, Thailand. She works on topics in insect physiology, insect molecular biology and enzymology.