Truffle volatiles inhibit growth and induce an oxidative burst in Arabidopsis thaliana.
The function of fungal volatiles in fungal-plant interactions is poorly understood. The aim here was to address this lack of knowledge, focusing on truffles, ectomycorrhizal fungi that are highly appreciated for their aroma. The effect of volatiles released by truffles was tested on Arabidopsis thaliana in a closed chamber bioassay. The volatiles produced by Tuber melanosporum, Tuber indicum and Tuber borchii fruiting bodies inhibited A. thaliana in terms of root length and cotyledon leaf size, and in some cases induced a bleaching of the seedlings, thus indicating toxicity. Ten synthetic volatiles were tested in a similar way. The strongest inhibitory effect was observed with C(8) molecules such as 1-octen-3-ol, an alcohol with a typical 'fungal smell'. Two of these C(8) compounds were further tested to investigate their mechanism of action. 1-Octen-3-ol and trans-2-octenal induced an oxidative burst (hydrogen peroxide, H(2)O(2)) in the A. thaliana leaves as well as a strong increase in the activities of three reactive oxygen species (ROS)-scavenging enzymes. These results demonstrate that fungal volatiles inhibit the development of A. thaliana and modify its oxidative metabolism. Even though limited to laboratory observations, these results indicate the presence of a hitherto unknown function of fungal volatiles as molecules that mediate fungal-plant interactions.
Splivallo
Richard
R
Department of Plant Biology, University of Torino, CEBIOVEM Centre of Excellence, Viale Mattioli 25, 10125 Torino, Italy.|IPP-CNR, Viale Mattioli 25, 10125 Torino, Italy.
Novero
Mara
M
Department of Plant Biology, University of Torino, CEBIOVEM Centre of Excellence, Viale Mattioli 25, 10125 Torino, Italy.|IPP-CNR, Viale Mattioli 25, 10125 Torino, Italy.
Bertea
Cinzia M
CM
Department of Plant Biology, University of Torino, CEBIOVEM Centre of Excellence, Viale Mattioli 25, 10125 Torino, Italy.
Bossi
Simone
S
Department of Plant Biology, University of Torino, CEBIOVEM Centre of Excellence, Viale Mattioli 25, 10125 Torino, Italy.
Bonfante
Paola
P
Department of Plant Biology, University of Torino, CEBIOVEM Centre of Excellence, Viale Mattioli 25, 10125 Torino, Italy.|IPP-CNR, Viale Mattioli 25, 10125 Torino, Italy.
D017360:Arabidopsis / Q000378:metabolism* / Q000382:microbiology; D001203:Ascomycota / Q000737:chemistry*; D017753:Ecosystem; D048690:Fruiting Bodies, Fungal / Q000737:chemistry; D006861:Hydrogen Peroxide; D018515:Plant Leaves / Q000378:metabolism / Q000382:microbiology; D017382:Reactive Oxygen Species / Q000378:metabolism*; D014835:Volatilization
D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide