Spatiotemporal Analyses of Tomato Brown Rugose Fruit Virus in Commercial Tomato Greenhouses

Abstract

Tomato brown rugose fruit virus (ToBRFV) is an emerging pathogen affecting tomato-production systems in several countries, including Mexico. This situation involves challenges due to the negative impact on yield and the lack of disease-management measures. This work analyzes the spatiotemporal distribution of ToBRFV in commercial tomato greenhouses. The presence or absence of diseased plants was evaluated weekly, assigning a location in space (x, y). Temporal analysis consisted of fitting the incidence to the monomolecular, logistic, log-logistic, Gompertz, exponential, Weibull, and Richard models, evaluated using the Akaike information criterion, significance, correlation, coefficient of determination, and root mean square error. Spatial analysis consisted of determining spatial aggregation using the Moran, Fisher, and Lloyd indices. In addition, spatial distribution was assessed by sequence observations, point patterns using the inverse distance index, and analysis by SADIE distance indicators. Results indicated that the logistic models (log-logistic and logistic) best described the temporal progress of ToBRFV. This disease also had slightly aggregated patterns in the initial phase, highly aggregated in the exponential phase, and uniform in the deceleration and stationary phases. This study demonstrates that the spatial and temporal dynamics of ToBRFV have important implications for the monitoring, diagnosis, management, and risk prediction of this disease.

A ToBRFV similar to a European isolate in a Mexican greenhouse, its presence in seeds and its inactivation for virus integrated management.

“…It is of paramount importance to consider the possible sources of infection during the exponential phase of infection, where an increase in the disease-transmission rate takes place [27,28].…”

Viruses of Economic Impact on Tomato Crops in Mexico: From Diagnosis to Management—A Review

“…The symptoms caused by ToBRFV are observed as mosaic patterns on leaves and a distortion of the leaf blade, and on some occasions, calyxes may present necrosis (Figure 1A-E) [35]. Tomato fruits may exhibit brown spots, wrinkles, deformation, and irregular ripening (Figure 1F-H) [33,36,37].…”

“…ToBRFV is widely spread across the world, with reports from the leading tomatoproducing countries, such as Jordan [32], Israel [33], Mexico [18], USA [39], Germany [40], the United Kingdom [41], Italy [42], Palestine [43], Turkey [44], China [36], the Netherlands (National Plant Protection Organization; https://english.nvwa.nl, accessed on 1 June 2021), Greece [45], Egypt [46], Spain [47], Iran [48], Saudi Arabia [49], Norway [50], France [51], and Switzerland [52]; additionally, some suspicious cases have been reported in Chile, Ethiopia, and Sudan, but these remain to be confirmed [53]. In Mexico, ToBRFV was first reported in 2018 at Yurécuaro and Tanhuato, Michoacán [18], as well as in tomato produced at Ensenada, Baja California [19]; however, the virus spread rapidly and is now present in every tomato-producing area of the country [35].…”

“…Hence, the relevance of ToBRFV relies on the severe losses it might cause to tomato crops as a result of symptoms on fruit. Moreover, ToBRFV is of major concern for protected agriculture due to the number of plants that are grown (up to 50,000 plants per ha) as well as further handling during cultural practices that can result in additional spread within a facility [35].…”

Tomato brown rugose fruit virus: An emerging and rapidly spreading plant RNA virus that threatens tomato production worldwide

“…As a proper control was lacking, the possible role of bumblebees in ToBRFV spread in this study needs to be confirmed. A more recent spatiotemporal investigation in tomato commercial greenhouses revealed that during a 24‐week culture period, ToBRFV was marginally aggregated at the initial stage, but vastly aggregated during the exponential phase of infection (González‐Concha et al, 2021 ). In this case, it was not clear if bumblebees were provided for pollination or not.…”