Location: Chemistry ResearchTitle: Production of the green leaf volatile (Z)-3-hexenal by a zea mays hydroperoxide lyase
Submitted to: Plants
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/21/2022
Publication Date: 8/25/2022
Citation: Yactayo Chang, J.P., Hunter III, C.T., Alborn, H.T., Christensen, S.A., Block, A.K. 2022. Production of the green leaf volatile (Z)-3-hexenal by a zea mays hydroperoxide lyase. Plants. 11(17):2201. https://doi.org/10.3390/plants11172201.
Interpretive Summary: The smell of freshly cut grass is due to the release of chemical odors known as green leaf volatiles (GLVs) from wounded or damaged plants. These GLVs help plants defend themselves against insect pests by attracting insects that eat or are parasites of the pests. USDA-ARS scientists from at the Center for Medical, Agricultural, and Veterinary Entomology in Gainesville FL have identified a gene in corn that produces these GLVs. Maintaining the presence of a functional version of this gene in corn breeding programs is therefore vital for stress resilient crop production. A caveat to this research, is that corn-adapted insect pests such as fall armyworm have mechanisms in their saliva to suppress GLV production in corn. This means that additional measures are required to control pests such as fall armyworm.
Technical Abstract: Hydroperoxide lyases (HPLs) are cytochrome P450’s from the CYP74B family that produce the green leaf volatile (Z)-3-hexenal from the cleavage of (9Z,11E,15Z)-octadecatrienoic acid. (Z)-3-hexenal is an important stress related signaling compound in plants and can be used as part of antiherbivore defenses. In this study we use phylogenetics to identify the maize HPL (ZmHPL) and demonstrate its ability to produce (Z)-3-hexenal in an Arabidopsis line deficient in HPL activity. Furthermore, we use gene expression analysis to show that expression of ZmHPL is induced in maize in response to herbivory by the insect pests Spodoptera frugiperda and Spodoptera exigua. Interestingly despite this induction S. frugiperda and S. exigua both suppress (Z)-3-hexenal production in maize showing that these insects can effectively overcome this aspect of the maize defense response.