AUTHOR=Lin Dong-jiang , Fang Yong , Li Ling-yun , Zhang Li-zhao , Gao San-ji , Wang Ran , Wang Jin-da 

TITLE=The insecticidal effect of the botanical insecticide chlorogenic acid on Mythimna separata (Walker) is related to changes in MsCYP450 gene expression

JOURNAL=Frontiers in Plant Science

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.1015095

DOI=10.3389/fpls.2022.1015095

ISSN=1664-462X

ABSTRACT=<p>The oriental armyworm <italic>Mythimna separata</italic> (Walker) (Lepidoptera: Noctuidae) can feed on the leaves of many crops, resulting in vast areas of damage and severe losses. Therefore, this insect has become a significant agricultural pest in north Asia. In this study, we fed 3<sup>rd</sup> instar larvae with artificial diets containing different concentrations of chlorogenic acid and found a significant lethal effect and the mortality increased with increasing chlorogenic acid concentration. Next, we measured the sublethal effect of chlorogenic acid at LC<sub>20</sub> on the growth and development of <italic>M. separata</italic> larvae. The durations of the 4<sup>th</sup> and 5<sup>th</sup> instar were longer than those of the control group (prolonged by 0.8 and 0.6 days, respectively), and the 6<sup>th</sup> instar was shorter (by 1.1 days). The total survival rate, pupation rate, eclosion rate, sex ratio, and oviposition amount in the LC<sub>20</sub> chlorogenic acid-treated group were significantly lower than those in the control group. Furthermore, transcriptome analysis of 3<sup>rd</sup> instar larvae fed various concentrations of chlorogenic acid revealed that several <italic>MsCYP450</italic> genes were significantly up-regulated, and this finding was further validated by qRT-PCR. In addition, various concentrations of chlorogenic acid and different treatment times significantly affected the enzyme activity of CYP450 in 3<sup>rd</sup> instar larvae. Importantly, dietary ingestion of dsMsCYP450 significantly reduced the mRNA level of <italic>MsCYP450</italic> genes and increased mortality in the presence of chlorogenic acid. Our results revealed that <italic>MsCYP6B6</italic>, <italic>MsCYP321A7</italic>, and <italic>MsCYP6B7-like</italic> play an essential role in the detoxification of chlorogenic acid by <italic>M. separata</italic>. This study provides evidence of control effect by botanical insecticide chlorogenic acid on <italic>M. separata</italic>, and potential detoxification mechanism mediated by P450 of botanical insecticide in arthropods.</p>