Effectiveness of disinfectants against the spread of tobamoviruses: Tomato brown rugose fruit virus and Cucumber green mottle mosaic virus

Abstract

Background Tobamoviruses, including tomato brown rugose fruit virus (ToBRFV) on tomato and pepper, and cucumber green mottle mosaic virus (CGMMV) on cucumber and watermelon, have caused many disease outbreaks around the world in recent years. With seed-borne, mechanical transmission and resistant breaking traits, tobamoviruses pose serious threat to vegetable production worldwide. With the absence of a commercial resistant cultivar, growers are encouraged to take preventative measures to manage those highly contagious viral diseases. However, there is no information available on which disinfectants are effective to deactivate the virus infectivity on contaminated hands, tools and equipment for these emerging tobamoviruses. The purpose of this study was to evaluate a collection of 16 chemical disinfectants for their effectiveness against mechanical transmission of two emerging tobamoviruses, ToBRFV and CGMMV. Methods Bioassay was used to evaluate the efficacy of each disinfectant based on virus infectivity remaining in a prepared virus inoculum after three short exposure times (10 s, 30 s and 60 s) to the disinfectant and inoculated mechanically on three respective test plants (ToBRFV on tomato and CGMMV on watermelon). Percent infection of plants was measured through symptom observation on the test plants and the presence of the virus was confirmed through an enzyme-linked immunosorbent assay with appropriate antibodies. Statistical analysis was performed using one-way ANOVA based on data collected from three independent experiments. Results Through comparative analysis of percent infection of test plants, a similar trend of efficacy among 16 disinfectants was observed between the two pathosystems. Four common disinfectants with broad spectrum activities against two different tobamoviruses were identified. Those effective disinfectants with 90–100% efficacy against both tobamoviruses were 0.5% Lactoferrin, 2% Virocid, and 10% Clorox, plus 2% Virkon against CGMMV and 3% Virkon against ToBRFV. In addition, SP2700 generated a significant effect against CGMMV, but poorly against ToBRFV. Conclusion Identification of common disinfectants against ToBRFV and CGMMV, two emerging tobamoviruses in two different pathosystems suggest their potential broader effects against other tobamoviruses or even other viruses.

Evaluation of responses to tomato brown rugose fruit virus (ToBRFV) and selection of resistant lines in Solanum habrochaites and Solanum peruvianum germplasm

“…There are many ways to prevent ToBRFV infections, such as seed treatment, sanitation, using disinfected materials, and grafting the plant on virus-resistant rootstock (Chanda et al 2021;Davino et al 2020;Samarah et al 2021;Spanò et al 2020). Nevertheless, the best way to its control would be the breeding and producing resistant varieties.…”

Seed Transmission of Three Viruses in Two Pear Rootstock Species Pyrus betulifolia and P. calleryana

“…We noticed that ASPV was detected in two out of 45 cotyledons of ASPV-negative Pc2, but not detected in true leaf samples of its seedlings. Some stable viruses, such as tobamoviruses, are carried as a contaminant on the seed coat, and cause seedling infection by mechanical transmission during the germination and first stages of growth [ 46 , 55 ]. Then, seed disinfection treatments were used to reduce virus infection [ 55 , 56 , 57 , 58 ].…”

“…Some stable viruses, such as tobamoviruses, are carried as a contaminant on the seed coat, and cause seedling infection by mechanical transmission during the germination and first stages of growth [ 46 , 55 ]. Then, seed disinfection treatments were used to reduce virus infection [ 55 , 56 , 57 , 58 ]. Although all seeds tested in this study were washed extensively under tap water during harvesting, we still could not exclude the contamination possibility of viruses on seeds, which possibly caused the occurrence of positive reactions of a few seeds and cotyledons from negative maternal trees.…”

“…Virus infection in rootstocks can result in substantial incidence on pear trees, which raises the need for an increased caution for virus infection during virus-free germplasm propagation and conservation. As used for some seed transmission viruses [ 55 , 56 , 57 , 58 ], seed disinfection treatments might be employed to reduce virus infection in pear rootstocks.…”

New Resources for the Specific and Sensitive Detection of the Emerging Tomato Brown Rugose Fruit Virus

“…ToBRFV induces a hypersensitive response in plants harboring these resistance genes [ 8 ], and infections of sweet pepper lacking these resistances have been reported in Italy [ 9 ]. On the other hand, the viral particle of ToBRFV is very stable and resilient to commonly used disinfectants [ 10 ], which may facilitate its mechanical transmission even by pollinators [ 11 ]. Taken together, the particular features of ToBRFV have contributed to its rapid spread worldwide [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ] since it was first reported in Israel and Jordan in 2014 [ 8 , 22 ].…”