Diversity of the Volatile Organic Compounds Emitted by 55 Species of Tropical Trees: a Survey in French Guiana

Abstract

Volatile organic compounds (VOCs) are produced by a broad range of organisms, from bacteria to mammals, and they represent a vast chemical diversity. In plants, one of the preeminent roles of VOCs is their repellent or cytotoxic activity, which helps the plant deter its predators. Most studies on VOCs emitted by vegetative parts have been conducted in model plant species, and little is known about patterns of VOC emissions in diverse plant communities. We conducted a survey of the VOCs released immediately after mechanical damage of the bark and the leaves of 195 individual trees belonging to 55 tropical tree species in a lowland rainforest of French Guiana. We discovered a remarkably high chemical diversity, with 264 distinct VOCs and a mean of 37 compounds per species. Two monoterpenes (alpha-pinene and limonene) and two sesquiterpenes (beta-caryophyllene and alpha-copaene), which are known to have cytotoxic and deterrent effects, were the most frequent compounds in the sampled species. As has been established for floral scents, the blend of VOCs is largely species-specific and could be used to discriminate among 43 of the 55 sampled species. The species with the most diverse blends were found in the Sapindales, Laurales, and Magnoliales, indicating that VOC diversity is not uniformly distributed among tropical species. Interspecific variation in chemical diversity was caused mostly by variation in sesquiterpenes. This study emphasizes three aspects of VOC emission by tropical tree species: the species-specificity of the mixtures, the importance of sesquiterpenes, and the wide-ranging complexity of the mixtures.

Identification of Soybean Resistance to Pod Sucking Bug (Riptortus linearis) by No-Choice Test

“…Dicke & Hilker (2003) reported that the plant defense against insect herbivores consists of direct defense which include trichomes (hairs on the plant), production of primary metabolites (protein inhibitor and an antioxidant enzyme), and the production of secondary metabolites (phenolic acids and isoflavones). In addition, the plant has indirect defense is through the production of volatile organic compounds such as methyl salicylate and cis-jasmone to attract natural enemies thus insect will avoid that plant (Courtois et al, 2009;Michereff et al, 2011).…”

Observations of sesquiterpenes and their oxidation products in central Amazonia during the wet and dry seasons

“…(2) This estimate derives from the available analysis of three essential oil types derived from Amazonian tree species: copaiba essential oil (this study; F. Soares et al, 2013), rosewood essential oil (Fidelis et al, 2012), and andiroba essential oil (this study). While these essential oils typically comprise ∼ 30 sesquiterpenes, Courtois et al (2009) report 169 sesquiterpenes emitted by 55 species of tropical trees. Thus, the impact of additional sesquiterpenes reported to be emitted from these plants but not found in the essential oils presented here is unaccounted for.…”

“…Chemical characterization of tropical plant tissue shows the presence of an abundance of sesquiterpenes (F. Courtois et al, 2012) and suggests their widespread emission from such vegetation (F. Courtois et al, 2009). Previous branch enclosure measurements of native Amazon saplings found that sesquiterpene emission was below detection limits (Bracho-Nuñez et al, 2013) even though sesquiterpenes have been observed within and outside the canopy of the central Amazon (Alves et al, 2016;Jardine et al, 2012).…”

Respon Genotipe Kedelai Biji Besar Dan Umur Genjah Terhadap Kompleks Hama Pengisap Polong

“…Trikoma serta ketebalan kulit polong menjadi faktor penghalang utama bagi pengisap polong untuk menusukkan stiletnya (Souza et al, 2012). Selain itu, tanaman juga memiliki pertahanan tidak langsung melalui produksi senyawa organik yang mudah menguap seperti metil salisilat dan cis-jasmone yang dapat menarik musuh alami untuk datang sehingga serangga akan menjauhi tanaman tersebut (Courtois et al, 2009;Michereff et al, 2011;Colazza & Wajnberg, 2013).…”