| Title: | Herbivory by leaf-cutter ants changes the glandular trichomes density and the volatile components in an aromatic plant model |
| Author(s): | Tozin L; Mayo Marques MO; Maria Rodrigues T; |
| Address: | "Department of Botany, Sao Paulo State University (UNESP), Institute of Biosciences of Botucatu (IBB), Botucatu, SP 18618-970, Brazil. Instituto Agronomico (IAC), Laboratory of Natural Products, Campinas, SP 13020-902, Brazil" |
| ISSN/ISBN: | 2041-2851 (Print) 2041-2851 (Electronic) |
| Abstract: | "Herbivory can induce several structural and functional alterations in the plant secretory system. Glandular trichomes are the main sites of production of volatile organic compounds (VOCs) with several chemical properties in Lamiaceae species. Ocimum species usually have three morphotypes of glandular trichomes (morphotype I is peltate and has a wide four-celled head; morphotype II is capitate and has a unicellular head; and morphotype III is capitate with a bicellular head) which produce a great amount of terpenes, although other chemical categories of substances are also produced. Despite the abundance of trichomes producing important anti-herbivory components in their leaves, the association between Ocimum species and leaf-cutter ants has been commonly registered in Brazil. We investigated the effect of leaf-cutter ant attack on the density of the glandular trichomes and on the chemistry of the VOCs released from leaves of O. gratissimum. Plants were subjected to Acromyrmex rugosus attack until 90 % of leaves were removed. After 40 days from the leaf-cutter attack, both treatments were sampled. The glandular trichome density was analysed by scanning electron microscopy. The VOCs were extracted utilizing headspace solid-phase microextraction (HS-SPME) technique and analysed by gas chromatography. Generally, the density of glandular trichomes increased in the adaxial leaf surface of the attacked plants. However, we bring novelties on this topic since we analysed the density of each morphotype separately. The morphotype I decreased in the abaxial leaf surface, and increased in the adaxial leaf surface; the morphotype II increased in both leaf surfaces; and the morphotype III decreased in the abaxial leaf surface and remained constant in the adaxial leaf surface of attacked plants. In leaves of attacked plants, the (Z)-beta-ocimene increased by 50 %, the alpha-selinene by 13 % and the germacrene D by 126 %, whereas the eugenol decreased by 70 %. Our data point to a differential response of each glandular morphotype in O. gratissimum and are consistent with the idea of a compartmentalization of functions among the different glandular morphotypes in the plant defence against environmental factors" |
| Keywords: | Acromyrmex rugosus Ocimum gas chromatography herbivore-induced plant volatiles (HIPVs) terpenes; |
| Notes: | "PubMed-not-MEDLINETozin, Luiz Ricardo Dos Santos Mayo Marques, Marcia Ortiz Maria Rodrigues, Tatiane eng England 2017/12/09 AoB Plants. 2017 Oct 24; 9(6):plx057. doi: 10.1093/aobpla/plx057. eCollection 2017 Nov" |
