Comparative Transcriptome Analysis of Sprouting Capabilities of Sweet Potato Storage Roots with Low and High Virus Levels

Sweet potato (Ipomoea batatas (L.) Lam.) is an important root crop in China, playing significant roles in ensuring national food security and increasing farmers’ income. The sprouting capability of sweet potato storage roots determines the quality of sweet potato seedlings and serves as a prerequisite for ensuring yield and quality. With the increasing severity of sweet potato viral diseases, the decline of the sprouting capability of seed roots has led to severe declines in both the yield and quality of sweet potatoes. It is urgent to uncover the genetic basis and molecular mechanisms underlying the sprouting capabilities of storage roots with different virus contents. In this study, storage roots with different virus contents of two sweet potato varieties, Jishu 25 (J25) and Jishu 26 (J26), were evaluated for sprouting capability and virus content, including chlorotic stunt virus (CSV), feathery mottled virus (FMV), sweet potato virus G (SPVG), sweet potato latent virus (SPLV), and sweet potato chlorotic fleck virus (SPCFV). The results show that the storage roots with low virus levels of both varieties exhibited stronger sprouting capability and lower virus content. Comparative transcriptome analysis of the differences in sprouting capabilities between storage roots with different virus content revealed that the starch metabolism, cellulose metabolism, jasmonic acid (JA) signaling pathway, and salicylic acid (SA) signaling pathways are potential biological pathways contributing to the differences in sprouting capabilities between storage roots with different virus contents. This study provides evidence for further research on the sprouting mechanisms of sweet potatoes.