AUTHOR=Mendoza-Mendoza Artemio , Esquivel-Naranjo Edgardo Ulises , Soth Sereyboth , Whelan Helen , Alizadeh Hossein , Echaide-Aquino Jesus Francisco , Kandula Diwakar , Hampton John G. TITLE=Uncovering the multifaceted properties of 6-pentyl-alpha-pyrone for control of plant pathogens JOURNAL=Frontiers in Plant Science VOLUME=Volume 15 - 2024 YEAR=2024 URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2024.1420068 DOI=10.3389/fpls.2024.1420068 ISSN=1664-462X ABSTRACT=Some volatile organic compounds (VOCs) produced by microorganisms have the ability to inhibit the growth and development of plant pathogens, induce the activation of plant defenses, and promote plant growth. Among them, 6-pentyl-alpha-pyrone (6-PP), a ketone produced by Trichoderma fungi, has emerged as a focal point of interest. 6-PP has been isolated and characterized from thirteen Trichoderma species and is the main VOC produced, often accounting for >50% of the total VOCs emitted. This review examines abiotic and biotic interactions regulating the production of 6-PP by Trichoderma, and the known effects of 6-PP on plant pathogens through direct and indirect mechanisms including induced systemic resistance. While there are many reports of 6-PP activity against plant pathogens, the vast majority have been from laboratory studies involving only 6-PP and the pathogen, rather than glasshouse or field studies including a host plant in the system. Biopesticides based on 6-PP may well provide an eco-friendly, sustainable management tool for future agricultural production. However, before this can happen, challenges including demonstrating disease control efficacy in the field, developing efficient delivery systems, and determining cost-effective application rates must be overcome before 6-PP's potential for pathogen control can be turned into reality. The impact of biotic stress on plant production, caused by attacks from pathogens and pests, has affected humanity's welfare since the early days of agricultural practices when crops were first cultivated (Howard, 1996). By the beginning of the twentieth century, there was optimism that both diseases and pests would ultimately be controlled with chemicals (Apple, 1977;Grube et al., 2011), but this was not realized, as in the early 1980s James (1981) estimated that global losses due to plant diseases were 12% of potential yield, which was equivalent to a monetary loss of US$50B at the production level. Global yield losses due to diseases and pests are even more prominent in the twentyfirst century, ranging from 17% to 47% depending on the crop, season, and location