Basidiomycetes are particularly sensitive to volatile organic compounds of Pseudomonas protegens
| Autor: | Prigigallo M.I., Mannerucci F., L'Haridon F., Anand A., Weisskopf L., Bubici G. |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: | |
| Zdroj: | Microbe-assisted crop production-Opportunities, challenges and needs (miCROPe), Vienna, Austria, 02-05/12/2019 info:cnr-pdr/source/autori:Prigigallo M.I., Mannerucci F., L'Haridon F., Anand A., Weisskopf L., Bubici G./congresso_nome:Microbe-assisted crop production-Opportunities, challenges and needs (miCROPe)/congresso_luogo:Vienna, Austria/congresso_data:02-05%2F12%2F2019/anno:2019/pagina_da:/pagina_a:/intervallo_pagine |
| Popis: | Volatile organic compounds (VOCs) play an important role in the communication among organisms, including plants, beneficial or pathogenic microbes, and pests. In vitro, we observed that the growth of many Basidiomycetes, including Heterobasidion abietinum, H. parviporum, Fomes fomentarius, Ganoderma lucidum, Phellinus pini, P. tuberculosus, and Rhizoctonia solani, was inhibited by VOCs of the biocontrol agent Pseudomonas protegens strain CHA0. On the other hand, Daedalea quercina was the only Basidiomycete that we found resistant. Intriguingly, in taxa outside Basidiomycota, the resistance to CHA0's VOCs seemed a rule with few exceptions. In fact, strains of Ascomycetes (Aspergillus sp., Penicillium sp., Fusarium oxysporum f. sp. cubense, Verticillium dahliae, and Pyrenochaeta lycopersici), Oomycetes (Pythium aphanidermatum), and Zygomycetes (Rhizopus sp.) were less sensitive or even resistant, with the Ascomycetes Alternaria tomatophila, Botrytis cinerea, and Sclerotinia sclerotiorum being the sensitive exceptions. Therefore, we used the system CHA0/H. abietinum and the overlapping plate method to study the mechanisms behind the fungal growth inhibition. Like CHA0, the derivative mutant CHA77, impaired for HCN production, was effective against H. abietinum, suggesting that HCN did not primarily participate in such inhibition. Remarkably, CHA0 emitted effective VOCs only when grown on certain media such as Luria-Bertani-agar (LBA), King's B agar, and peptone-agar, but not on potato-dextrose-agar (PDA). VOCs from LBA- and PDA-cultures of CHA0 were sampled using a closed-loop stripping method and analyzed by gas chromatography coupled to mass spectrometry (GC/MS). Comparative analysis of the volatilomes emitted on both media unveiled the candidate molecules very likely involved in the detrimental effect on H. abietinum growth. In the overlapping plate system, one colony of CHA0 was enough to drastically limit the growth of H. abietinum, and two or more colonies stopped completely the fungal growth, either if a young mycelium plug or a 3-, 5- or 7-day old fungal colony was exposed. Scanning electron microscopy revealed that hyphae exposed to VOCs were severely damaged as they became suddenly shrunk, abnormally branched, and with depressed lesions in the cell wall. It was impressive that such injuries occurred as soon as 15 minutes after the exposure to VOCs, increased in intensity afterward, and 7 days after exposure the hyphae were absolutely unrecognizable. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|