Fungal F8-Culture Filtrate Induces Tomato Resistance against Tomato Yellow Leaf Curl Thailand Virus

Abstract

Tomato (Solanum lycopersicum) is an important economic crop worldwide. However, tomato production is jeopardized by the devastating tomato yellow leaf curl disease (TYLCD) caused by whitefly-transmitted begomoviruses (WTBs). In this study, we evaluated the efficacy of our previously developed plant antiviral immunity inducer, fungal F8-culture filtrate, on tomato to combat tomato yellow leaf curl Thailand virus (TYLCTHV), the predominant WTB in Taiwan. Our results indicated that F8-culture filtrate treatment induced strong resistance, did not reduce the growth of tomato, and induced prominent resistance against TYLCTHV both in the greenhouse and in the field. Among TYLCTHV-inoculated Yu-Nu tomato grown in the greenhouse, a greater percentage of plants treated with F8-culture filtrate (43–100%) were healthy-looking compared to the H2O control (0–14%). We found that TYLCTHV cannot move systemically only on the F8-culture filtrate pretreated healthy-looking plants. Tracking the expression of phytohormone-mediated immune maker genes revealed that F8-culture filtrate mainly induced salicylic acid-mediated plant immunity. Furthermore, callose depositions and the expression of the pathogen-induced callose synthase gene, POWDERY MILDEW RESISTANT 4 were only strongly induced by TYLCTHV on tomato pretreated with F8-culture filtrate. This study provides an effective way to induce tomato resistance against TYLCTHV.

Systemic resistance induced in tomato plants by Beauveria bassiana‐derived proteins against tomato yellow leaf curl virus and aphid Myzus persicae

“…Similarly, our results are in accordance with the findings of Chiu et al 36 . who showed under both laboratory and field conditions the induction of strong resistance in tomato plants against tomato yellow leaf curl Thailand virus (TYLCTHV) by the application of a plant antiviral immunity inducer F8‐culture filtrate isolated and characterized from a basidiomycetous yeast‐like fungus Trichosporon spp .…”

“…Similarly, our results are in accordance with the findings of Chiu et al 36 who showed under both laboratory and field conditions the induction of strong resistance in tomato plants against tomato yellow leaf curl Thailand virus (TYLCTHV) by the application of a wileyonlinelibrary.com/journal/ps plant antiviral immunity inducer F8-culture filtrate isolated and characterized from a basidiomycetous yeast-like fungus Trichosporon spp. Previously, this fungal filtrate (F8-culture) has been shown to induce significant resistance in N. benthamiana plants against the infection of tobacco mosaic virus (TMV).…”

“…33 Later studies explored that the induced systemic resistance in tobacco and tomato plants is manifested by triggering of plant SA related defense pathways by a F8-polysaccharide. 36,37 Interestingly, elicitor protein PeBb1 used in this study has been demonstrated to upregulate the expression levels of SA, JA and ET related plant defense genes in different plants against various sucking and chewing insect pests. 17,20,28,38 Djonović et al 39 showed that a small elicitor protein (designated as Sm1) derived from a biocontrol fungus Trichoderma virens induced systemic resistance in cotton plants against foliar infection by Colletotrichum sp.…”

“…Previously, this fungal filtrate (F8‐culture) has been shown to induce significant resistance in N. benthamiana plants against the infection of tobacco mosaic virus (TMV) 33 . Later studies explored that the induced systemic resistance in tobacco and tomato plants is manifested by triggering of plant SA related defense pathways by a F8‐polysaccharide 36,37 . Interestingly, elicitor protein PeBb1 used in this study has been demonstrated to upregulate the expression levels of SA, JA and ET related plant defense genes in different plants against various sucking and chewing insect pests 17,20,28,38 .…”

Special Issue “State-of-the-Art Plant–Virus Interactions in Asia”

“…On the other hand, several groups provided in-depth analyses of the regulations of antiviral host factors. Chiu, Y. S. and coworkers revealed that fungal F8-culture filtrate may induce the expression of certain defense-related genes which conferred resistance against tomato yellow leaf curl Thailand virus in tomato plants [ 9 ]. Sanobar and collaborators compared the functions of HEN1, responsible for small RNA methylation in RNA silencing mechanism, in angiosperm and bryophyte plants under the inhibition of a viral suppressor of RNA silencing, HC-Pro [ 10 ].…”