Morphological and molecular characteristics of Liriomyza sp. (Diptera: Agromyzidae) on onion plants (Allium cepa L.) in Bali

Liriomyza sp. leafminer fly is an important pest of shallot crops that spread widely in Southeast Asia and Pacific regions such as Indonesia, China, Japan, Korea, Thailand, Malaysia, Singapore, Taiwan and Vietnam. This study aims to identify the type of Liriomyza species attacking onion plants in Bali, Indonesia through morphological and molecular characterization. Onion leaf samples showing symptoms of Liriomyza attack, taken from the study site, were subsequently cultured in the laboratory. Adult flies obtained from breeding were then identified based on their morphological characteristics. While the molecular characteristics were identified through several steps: DNA isolation, DNA electrophoresis, PCR chain reaction, then put back into the re-electrophoresis box, and finally sequencing method was applied. The results showed that the Liriomyza species was found to have a morphological characteristic such that it has a simple color pattern on a simple abdomen with no connecting line between the segments and the next segment, dark grey or near black scutellum. These characteristics refer to the species L. chinensis. GenBank data tracking results through identification of squamous alignment results indicate that the Liriomyza COI nucleic acid found showed the highest homology with L. chinensis (EF104701.1), L. chinensis (AB721340.1) and L. chinensis (AB721343.1) with identical rate of 99%. Based on the results then Liriomyza species found attacking onion planting on the island of Bali is L. chinensis.