Comparative transcriptome provides insights into gene regulation network associated with the resistance to in grafted wax gourd .

INTRODUCTION

Wilt is a soil-borne disease caused by that has become a serious threat to wax gourd production. Disease-resistant graft wax gourds are an effective treatment for wilt. However, there are few reports on the defense mechanism of graft wax gourd against wilt diseases.

METHODS

In the present study, disease and growth indices were compared between grafted and original wax gourds after infection with . High level of disease resistance was observed in the grafted wax gourd, with a lower disease index and low impacts on growth after infection. RNA-seq was performed to identify the differentially expressed genes (DEGs) between the adjacent treatment time points in the grafted and original wax gourds, respectively. Then a comparative temporal analysis was performed and a total of 1,190 genes were identified to show different gene expression patterns between the two wax gourd groups during infection.

RESULT AND DISCUSSION

Here, high level of disease resistance was observed in the grafted wax gourd, with a lower disease index and low impacts on growth after infection. The DEG number was higher in grafted group than original group, and the enriched functional categories and pathways of DEGs were largely inconsistent between the two groups. These genes were enriched in multiple pathways, of which the mitogen-activated protein kinase (MAPK) signaling pathway enhanced the early defense response, and cutin, suberin, and wax biosynthesis signaling pathways enhanced surface resistance in grafted wax gourd in comparison to original group. Our study provides insights into the gene regulatory mechanisms underlying the resistance of grafted wax gourds to wilt infection, which will facilitate the breeding and production of wilt-resistant rootstocks.