The Role of Volatile Organic Compounds in Plant Resistance to Abiotic Stresses: Responses and Mechanisms

Why plants constitutively emit certain volatile organic compounds is a question that has attracted numerous researchers since the discovery of emissions. A number of hypotheses exist regarding the role of constitutive volatile organic compounds and many of these highlight the role of these compounds in enhancing plant tolerance to certain abiotic stresses. As practically any stress can modify constitutive emissions and also elicit production of novel compounds (induced emissions), this chapter provides a review of the hypotheses with particular foci on the key environmental stresses – heat and drought. Furthermore, we discuss how changes in the atmospheric CO2 concentration over past and future geologic epochs are likely to affect the role of volatile organic compounds as an adaptation to abiotic stresses.