Metabolomic Analysis of Cassava Cultivars in Response to Sri Lankan Cassava Mosaic Virus Infection by Viruliferous Whiteflies

Cassava mosaic disease, caused by Cassava mosaic begomoviruses in the family Geminiviridae, poses a major threat to cassava production, with Sri Lankan cassava mosaic virus (SLCMV) being the dominant strain in Southeast Asia. Transmitted via infected propagative stems and whiteflies (Bemisia tabaci), SLCMV's impact on cassava metabolite dynamics remains poorly understood. This study investigated metabolite profile changes in resistant, tolerant, and susceptible cassava cultivars at 1, 3, and 7 days after inoculation by viruliferous whiteflies. Distinct metabolite patterns were observed among cultivars, with several pathways linked to plant defense identified, including flavonoid biosynthesis, phenylpropanoid biosynthesis, and purine metabolism. Secondary metabolite pathways, such as the energy-signaling SnRK1/AMPK-liked proteins, alpha-linolenic acid metabolism, and starch and sucrose metabolism, were also implicated. The results provide insights into metabolite-mediated defense mechanisms during early and late infection, enhancing understanding of cassava's responses to SLCMV inoculation after exposure to viruliferous whitefly infestation. This study supports the development of SLCMV-resistant cassava cultivars.