Transcriptome Analysis of Watermelon Leaves Reveals Candidate Genes Responsive to Cucumber green mottle mosaic virus Infection.

Yuyan Sun,Min Fan,Yanjun He

doi:10.3390/ijms20030610

Abstract

Cucumber green mottle mosaic virus (CGMMV) is a member of the genus Tobamovirus, which cause diseases in cucurbits, especially watermelon. In watermelon, symptoms develop on the whole plant, including leaves, stems, peduncles, and fruit. To better understand the molecular mechanisms of watermelon early responses to CGMMV infection, a comparative transcriptome analysis of 24 h CGMMV-infected and mock-inoculated watermelon leaves was performed. A total of 1641 differently expressed genes (DEGs) were identified, with 886 DEGs upregulated and 755 DEGs downregulated after CGMMV infection. A functional analysis indicated that the DEGs were involved in photosynthesis, plant–pathogen interactions, secondary metabolism, and plant hormone signal transduction. In addition, a few transcription factor families, including WRKY, MYB, HLH, bZIP and NAC, were responsive to the CGMMV-induced stress. To confirm the high-throughput sequencing results, 15 DEGs were validated by qRT-PCR analysis. The results provide insights into the identification of candidate genes or pathways involved in the responses of watermelon leaves to CGMMV infection.

Highlights

Watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] is an important cucurbit crop grown worldwide
In Cucumber green mottle mosaic virus (CGMMV)-infected watermelon, mottling and mosaic develop on the leaves, brown necrotic lesions develop on the stems and peduncles, and the flesh becomes spongy and rotting, with dirty red discolorations [9]
The results showed that even that though nothough obvious symtoms developed in hpi watermelon leaves, the virus has accumulated in the plants at the early developed in 24 hpi watermelon leaves, the virus has accumulated in the plants at the early infectious infectious time

Summary

Introduction

Watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] is an important cucurbit crop grown worldwide. In 2016, approximately 117 million tons of watermelon were produced, accounting for 10.9% of total global vegetable production China was the leading country, producing approximately 79 million tons of watermelon, which constituted 67.7% of the worldwide production (available online: http://www.fao.org/faostat). CGMMV is readily spread by contact, and pollen and seed transmission [2] Since it was first report in 1935 in England, where it was found to cause diseases in cucumber [3,4], CGMMV has achieved a global distribution, being present in more than 30 countries, and has become a major threat to cucurbit-based industries [5,6,7,8]. In CGMMV-infected watermelon, mottling and mosaic develop on the leaves, brown necrotic lesions develop on the stems and peduncles, and the flesh becomes spongy and rotting, with dirty red discolorations [9]

Methods

Results

Discussion

Conclusion