Transcriptome and metabolome analyses provide crucial insights into the adaptation of chieh-qua to infection.

Introduction: Chieh-qua ( Cogn. How) is a wax gourd variety that is generally susceptible to infection and damage by during its cultivation. Therefore, analyzing the adaption mechanism of chieh-qua to infection is of great significance for cultivating resistant varieties.

Methods: Through comparative transcriptome analysis, comparative metabolome analysis, integrated analysis of transcriptome and metabolome and between infected samples and control samples of susceptible lines.

Results: This study found that proteins such as NPR1, TGA and PR1 in plant hormone signal transduction pathway were up-regulated after infection, which may activate a series of plant secondary metabolic synthesis pathways. In addition, the expression of 27 genes in the flavonoid biosynthetic process in resistant lines after infection was significantly higher than that in susceptible lines, indicating that these genes may be involved in fungal resistance. This study also found that alternative splicing of genes may play an important role in responding to infection. For example, plant protein kinase genes such as EDR1, SRK2E and KIPK1 were not differentially expressed after infection, but the transcripts they produced differ at the transcription level. Finally, through comparative metabolome analysis, this study identified potentially functional substances such as oxalic acid that increased in content after infection. Through integrated analysis of transcriptome and metabolome, some differential expressed genes significantly related to differential metabolites were also identified.

Discussion: This study provides a basis for understanding and utilizing chieh-qua's infection mechanism of through analysis of the transcriptome and metabolome.