Lei-Lei Li, Huan-Huan Zhao, C. Kong
Nov 2, 2019
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0
Influential Citations
36
Citations
Journal
Journal of experimental botany
Abstract
Neighbor detection and allelochemical response are important mediators in plant-plant interactions. Despite increasing knowledge of plant allelochemicals in response to the presence of competitors involved in the neighbor-derived signaling chemicals, less is known about which signaling chemicals are responsible for the neighbor-induced allelochemical response. Here, we experimentally demonstrated (-)-loliolide, a carotenoid metabolite, as a signaling chemical in barnyardgrass-rice allelopathic interactions. The production of rice allelochemicals momilactone B and tricin was increased in the presence of five biotypes of barnyardgrass. (-)-Loliolide was found in all biotypes of barnyardgrass and their root exudates and rhizosphere soils. There were significant positive relationships between rice allelechemicals and (-)-loliolide concentrations across biotypes of barnyardgrass. Furthermore, (-)-loliolide elicited the production of momilactone B and tricin. Comparative transcriptome analysis showed regulation of (-)-loliolide on diterpenoid and flavonoid biosynthesis pathway. The expression of key genes involved in the biosynthesis of momilactone B (CPS4, KSL4 and MAS) and tricin (CYP75B3 and CYP75B4) was up-regulated by (-)-loliolide. These findings suggest that (-)-loliolide as a signaling chemical participates in barnyardgrass-rice allelopathic interactions. Through the signaling chemical, allelopathic rice plants can detect competing barnyardgrass and respond by increasing allelochemical levels to provide an advantage for their own growth.