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

Authors: Chanda, Bidisha; Shamimuzzaman, Md - Shamim; Gilliard, Andrea; Ling, Kai-Shu

Submitted to: Virology Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/21/2020
Publication Date: 1/6/2021
Citation: Chanda, B., Shamimuzzaman, M., Gilliard, A.C., Ling, K. 2021. Effectiveness of disinfectants against the spread of tobamoviruses: tomato brown rugose fruit virus and cucumber green mottle mosaic virus. Virology Journal. 18:7. https://doi.org/10.1186/s12985-020-01479-8.
DOI: https://doi.org/10.1186/s12985-020-01479-8

Interpretive Summary: Several emerging seed-borne tobamoviruses, including tomato brown rugose fruit virus (ToBRFV) and cucumber green mottle mosaic virus (CGMMV), post serious threats to profitable production of several important vegetable crops, including tomato, pepper, cucumber and watermelon. Due to the lack of a resistant cultivar or the resistance breaking by these emerging viruses, the best solution is through prevention of a virus infection through hygiene and the use of a disinfectant. In this study, ARS scientists in Charleston, SC evaluated the efficacy of 16 chemicals for their effects in deactivating virus infectivity of ToBRFV on tomato and CGMMV on watermelon. The screening results revealed several common disinfectants with broad spectrum activities against both tobamoviruses. Disinfectants with 90-100% efficacy against either of two tobamoviruses included Virocid, Clorox, Lactoferrin and Virkon. in addition, SP2700 generated good effects on CGMMV, but with poor results on ToBRFV. The identification of several common disinfectants against two distinctive tobamoviruses in different host plants suggest their broader effects against other viruses. The results of this study will be useful to vegetable growers, seed industry, University researchers and extension agents.

Technical Abstract: With seed-borne, mechanical transmission and resistant breaking, tobamoviruses have emerged as a major threat to profitable productions for a number of economically important vegetables, including tomato, pepper, watermelon and cucumber worldwide. In the present study, we focused our efforts in evaluating 16 chemical disinfectants for their effectiveness against mechanical transmission of two emerging tobamoviruses, tomato brown rugose fruit virus (ToBRFV) on tomato and cucumber green mottle mosaic virus (CGMMV) on watermelon. Each disinfectant was treated with the experimental virus inoculum for a short exposure time (less than 60 sec) and administered on appropriate host plants (tomato for ToBRFV and watermelon for CGMMV) through mechanical inoculation simulating tool dipping and plant handling. Evaluation of efficiency of each disinfectant was based on virus infectivity remained, measured through symptom observation on test plants at 3-4 weeks post inoculation followed by appropriate laboratory tests, including enzyme-linked immunosorbent assay. The initial screening results revealed several common disinfectants with broad spectrum activities against the two different tobamoviruses, with some minor differences. The efficacy of some promising disinfectants were confirmed through additional experiments against the respective virus. and their potential phytotoxicity was monitored on the treated plants. Disinfectants generated promising results with 90-100% efficacy against either of the tobamoviruses, including 2% Virocid, 10% Clorox 0.5% Lactoferrin and Virkon (2% against CGMMV and 3% against ToBRFV). SP2700 generated a good effect against the spread of CGMMV, but poorly on ToBRFV. Identification of common disinfectants against two distinctive tobamoviruses on two separate host plants suggest their broader effects against tobamoviruses or even other viruses.