Opportunities and Challenges in Studies of Host-Pathogen Interactions and Management of Verticillium dahliae in Tomatoes

Abstract

Tomatoes (Solanum lycopersicum L.) are a valuable horticultural crop that are grown and consumed worldwide. Optimal production is hindered by several factors, among which Verticillium dahliae, the cause of Verticillium wilt, is considered a major biological constraint in temperate production regions. V. dahliae is difficult to mitigate because it is a vascular pathogen, has a broad host range and worldwide distribution, and can persist in soil for years. Understanding pathogen virulence and genetic diversity, host resistance, and plant-pathogen interactions could ultimately inform the development of integrated strategies to manage the disease. In recent years, considerable research has focused on providing new insights into these processes, as well as the development and integration of environment-friendly management approaches. Here, we discuss the current knowledge on the race and population structure of V. dahliae, including pathogenicity factors, host genes, proteins, enzymes involved in defense, and the emergent management strategies and future research directions for managing Verticillium wilt in tomatoes.

Keywords: Solanum Lycopersicon L.; Verticillium dahliae; disease resistance; integrated disease management; plant-pathogen interactions; tomato.

Figure 1

Tomato production by region (A) and top 10 tomato-producing countries in the world in 2018 (B). Adapted and modified from [1]

Figure 2

Worldwide distribution of Verticillium dahliae. Circles represent the locations (states and provinces) where V. dahliae has been reported. Adapted from [16].

Figure 3

A proposed schematic illustration of the plant microbiome impact on Verticillium dahliae protection, and crop productivity, and crop yield. Generation concepts and mechanisms of defense, and novel approaches, were adapted and modified from previous publications [178,181,182,183,184,185,186,187,188,190,191].

Figure 4

A proposed flow-chart to develop Verticillium wilt-resistant tomato varieties by genome-based approaches and new plant breeding techniques adapted and modified from previous publications [192,193,194,195,196,197,198,199,200,201,202,203,205,212,221,222,223,224,225].