Induction of Volatile Terpene Biosynthesis and Diurnal Emission by Methyl Jasmonate in Foliage of Norway Spruce

Abstract

Terpenoids are characteristic constitutive and inducible defense chemicals of conifers. The biochemical regulation of terpene formation, accumulation, and release from conifer needles was studied in Norway spruce [Picea abies L. (Karst)] saplings using methyl jasmonate (MeJA) to induce defensive responses without inflicting physical damage to terpene storage structures. MeJA treatment caused a 2-fold increase in monoterpene and sesquiterpene accumulation in needles without changes in terpene composition, much less than the 10- and 40-fold increases in monoterpenes and diterpenes, respectively, observed in wood tissue after MeJA treatment (D. Martin, D. Tholl, J. Gershenzon, J. Bohlmann [2002] Plant Physiol 129: 1003–1018). At the same time, MeJA triggered a 5-fold increase in total terpene emission from foliage, with a shift in composition to a blend dominated by oxygenated monoterpenes (e.g. linalool) and sesquiterpenes [e.g. (E)-β-farnesene] that also included methyl salicylate. The rate of linalool emission increased more than 100-fold and that of sesquiterpenes increased more than 30-fold. Emission of these compounds followed a pronounced diurnal rhythm with the maximum amount released during the light period. The major MeJA-induced volatile terpenes appear to be synthesized de novo after treatment, rather than being released from stored terpene pools, because they are almost completely absent from needle oleoresin and are the major products of terpene synthase activity measured after MeJA treatment. Based on precedents in other species, the induced emission of terpenes from Norway spruce foliage may have ecological and physiological significance.

<sup>13</sup>C labelling study of constitutive and stress-induced terpenoide missions from Norway spruce and Scots pine

“…This conclusion agrees with other studies on stress-induced emissions (Loughrin et al, 1994;Pare and Tumlinson, 1997;Martin et al, 2003;Brilli et al, 2009) wherein it is shown that insect induced terpenoid emissions as well as induced emissions from the shikimate pathway are mainly de novo emissions. In contrast, the constitutive monoterpene 20 emissions from both conifers had much lower de novo fractions (Table 3) with values quite consistent to the empirical light dependent factor (LDF) given by Guenther et al (2012) with values ranging from 0.05 to 0.1 for most monoterpenes.…”

“…Helmig et al (2007) studied the light intensity dependence of sesquiterpene emissions from a loblolly pine tree (Pinus taeda L.) and found that the nighttime emissions under elevated temperature conditions were only 15 slightly lower than the daytime emissions at similar temperatures, i.e., the light dependence was not significant. Similarly, nocturnal emissions of around 30 % of the daytime fluxes were observed for the herbivore induced sesquiterpenes from Norway spruce (Martin et al, 2003). These results together with our study strongly suggest that the light intensity dependence of sesquiterpene emissions is different from that described for isoprene and de novo emitted monoterpenes, and may vary from individual to individual of the same species.…”

Cascading effects of induced terrestrial plant defences on aquatic and terrestrial ecosystem function

“…In order to further induce plant defences, we applied jasmonates because a chemical treatment is a more controlled and reliable method than introducing herbivores. There have been extensive laboratory studies on the role that jasmonates play in inducing plant defences [50,51], but there are far fewer studies that have successfully used jasmonates to induce defence production in the foliage of trees in nature [52][53][54].…”

Cloning and Characterization of Naringenin 8-Prenyltransferase, a Flavonoid-Specific Prenyltransferase of Sophora flavescens

“…Although some secondary metabolites are translocated from source cells to sink organs, these results indicated that prenylated flavonoids are biosynthesized only in the root bark of S. flavescens, and are not transferred to peeled root and aerial parts. Furthermore SfN8DT-1 expression in cultured cells was strongly induced by yeast extract, MJ and salicylic acid, which mimics insect and pathogen attacks (Martin et al, 2002;Martin et al, 2003; Fig. 5A), indicative that this gene plays an important role as a defense reaction against insect and pathogen attack in S. flavescens root.…”