BIOLOGICAL RESPONSE AND MOLECULAR IDENTIFICATION OF THE BEGOMOVIRUS INFECTION IN THE NEW INDONESIAN MELON GENOTYPE KINAYA

Melon farming faces difficulties due to climate change causing unstable conditions, which make the plants more vulnerable to viruses like Begomovirus, leading to lower melon yields. To tackle this problem and guarantee a stable food supply, it is crucial to create melon varieties that possess resistance to these viruses by utilizing breeding techniques. Kinaya is a new genotype being developed as a Begomovirus tolerant variety for future prospects. Further observations are needed on the initial identification of biological responses to Begomovirus infection and the presence of candidate resistance genes in Kinaya. The research was conducted in open farmland in Jamusan, Yogyakarta, Indonesia, from April to August 2021. Observations and data were collected using the plant leaf infection scoring method based on the severity of symptoms in the Kinaya population. Melon and virus genomes were isolated from melon leaves exhibiting Begomovirus symptoms and from healthy plant leaves. We employed a set of 8 melon samples for dual objectives: identifying Begomovirus using Krusty-Homer primers and detecting Begomovirus resistance genes through SCAR primers linked to candidate resistance genes targeting Begomovirus. Observations showed symptoms of infection with yellow spot and leaf curling with tolerant susceptibility. Molecular identification with Krusty-Homer confirmed the presence of Begomovirus infection in all infected samples. Over 90 sequence similarity of the coat protein DNA virus was found in different Begomovirus species. SLCCV and ToLCNDV isolates from Indonesia were found to be closely related. Based on the developed SCAR markers, the DNA band of 900 bp was found in all healthy samples. Kinaya shows potential to be developed into a leading virus-resistant melon variety in Indonesia, although further research is needed to stabilize its resistant traits. © 2017 Pak. J. Phytopathol. All rights reserved.