Abstract
Maize ( Zea mays) is a staple cereal crop cultivated all over the world but that is threatened by various insects. Feeding of the lepidopteran insect Mythimna separata triggers defence signalling and increases anti-herbivore benzoxazinoids (Bxs) in the insect-damaged maize leaves. However, the herbivory-elicited within-leaf and leaf-to-leaf systemic signalling in maize remains largely unexplored. Here, we show that simulated M. separata herbivory and mechanical wounding elicited increased levels of jasmonic acid (JA), JA-Ile (JA-isoleucine conjugate) and Bxs in the damaged areas and in specific systemic regions within a leaf. Importantly, increased contents of Bxs were detected in a systemic leaf, and consistently, this leaf exhibited increased defence against M. separata. Increased JA/JA-Ile and altered transcriptome, including Bx biosynthesis genes, were detected in systemic leaves after wounding or simulated herbivory treatments, although only simulated herbivory induced increase of the contents of Bxs systemically. Promoter and co-expression analysis revealed that transcription factors bHLH57 and WRKY34 may regulate Bx biosynthesis genes in systemic leaves. Moreover, leaf ablation experiment indicated that the systemic signal rapidly exited the local leaves within 30 min after elicitation. This study provides new insight into the temporal and spatial regulation of defence responses of maize against lepidopteran insects. This article is part of the theme issue 'Biotic signalling sheds light on smart pest management'.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Philosophical Transactions of the Royal Society B: Biological Sciences
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.