AUTHOR=Guo Hong Gang , Miao Shuang Zhen , Ai Peng Peng , Zhang Min Zhao , Yan Zhe , Du Yan Li 

TITLE=Bioactive volatile compounds from Penicillium digitatum-infected apples: Oviposition attractants for yellow peach moth Conogethes punctiferalis (Lepidoptera: Crambidae)

JOURNAL=Frontiers in Sustainable Food Systems

VOLUME=7

YEAR=2023

URL=https://www.frontiersin.org/journals/sustainable-food-systems/articles/10.3389/fsufs.2023.1119717

DOI=10.3389/fsufs.2023.1119717

ISSN=2571-581X

ABSTRACT=<sec><title>Introduction</title><p>Plant-associated microbes critically shape the dynamics of plant-and insect-associated communities. In previous studies, we reported that the yellow peach moth <italic>Conogethes punctiferalis</italic> (YPM) preferred to <italic>Penicillium digitatum-infected</italic> apples (PDA) for oviposition. However, the underlying mechanisms remains unclear.</p></sec><sec><title>Methods</title><p>In the present study, the behavioral and physiological experiments were conducted to determine how <italic>P. digitatum</italic> affects the oviposition selection of mated YPM females <italic>via</italic> altering host plant volatile organic compounds (VOCs).</p></sec><sec><title>Results</title><p>Mated YPM females were attracted to and laid more eggs on PDA than on non-infected apples (NIA), mechanically damaged apples (MDA), and <italic>P. digitatum</italic> in potato dextrose agar medium (PPD) in the oviposition selection experiments. Four-arm olfactometer assays further confirmed that odors in PDA were responsible for the attractiveness of mated YPM females. Further analyses showed that 38 VOCs were collected and identified from all treatments by GC-MS, with five specific VOCs (methyl 2-methylbutyrate, styrene, methyl caproate, butyl caprylate, and <italic>n</italic>-tetradecane) emitting from PDA. A principal component analysis (PCA) based on the absolute contents of 38 VOCs revealed a clear separation of PDA from NIA, MDA, and PPD. Moreover, when <italic>P. digitatum-</italic>induced specific VOCs were added to apples in individual or synthetic blends, there was a significantly higher percentage of mated YPM females to apples with individual or synthetic blends consisting of methyl 2-methylbutyrate, butyl caprylate, or <italic>n</italic>-tetradecane in Y-tube olfactometer experiments, suggesting that these three specific VOCs acted as predominant olfactory signals for mated YPM females to PDA.</p></sec><sec><title>Discussion</title><p>Taken together, the microbe <italic>P. digitatum</italic> was an important driver of the interactions between YPMs and host plants by altering plant volatiles. These findings may form the basis for developing attractant baits for field trapping YPMs in the future.</p></sec>