Volume 20, Issue 9, Pages R392-R397 (May 2010) Plant volatiles  Ian T. Baldwin  Current Biology  Volume 20, Issue 9, Pages R392-R397 (May 2010) DOI: 10.1016/j.cub.2010.02.052 Copyright © 2010 Elsevier Ltd Terms and Conditions

Figure 1 Biosynthetic origins of plant volatiles. The majority of plant volatiles are derived from four biosynthetic classes: terpenoids, fatty acid catabolites, aromatics, and amino-acid derived products. Green leaf volatiles are produced from the oxidative cleavage of fatty acids. Many of these products are made more lipophilic before their release by removing or masking hydrophilic functional groups through reduction, methylation or acylation reactions. Many different metabolic pathways contribute to the volatiles that are released, and hence the volatile metabolome contains information about the plant's metabolic status. Figure modified from Pichersky et al. (see Further reading). Current Biology 2010 20, R392-R397DOI: (10.1016/j.cub.2010.02.052) Copyright © 2010 Elsevier Ltd Terms and Conditions

Figure 2 Plant volatiles function in protecting against biotic and abiotic stresses and in signaling that can be both beneficial and detrimental to the emitting plant. (A) Schematic depicting the diverse functional consequences of emitting volatiles for a plant. Numbers refer to organisms depicted in (B). Figure modified from Unsicker et al. (see Further reading). (B) Organisms known to pay attention to plant volatiles emitted from Nicotiana attenuata, a native tobacco, whose ability to release or perceive particular volatiles has been genetically manipulated by transformation; the interactions have been studied in the plant's native habitat in the Great Basin Desert in southwestern USA. 1,2: adults and larvae of Manduca sexta and M. quinquemaculata; 3: hummingbirds; 4: Epitrix flea beetles; 5: seed collecting ants; 6: Geocorus predators; 7: beneficial endophytic Bacillus microbes; 8: neighboring N. attenuata seedlings. Current Biology 2010 20, R392-R397DOI: (10.1016/j.cub.2010.02.052) Copyright © 2010 Elsevier Ltd Terms and Conditions