Potential use of essential oils to enhance heat tolerance in plants

Abstract

Isothiocyanates, monoterpenes, and leaf volatiles that are components of essential oils induce the expression of heat shock protein genes in plant systems. Here, the modes of heat shock responses induced by the essential oil compounds and their heat-tolerance-enhancing activities are described. Traditionally, green manure produced from essential-oil-containing plants has been used because such manure is thought to have beneficial effects in fertilizing, allelopathic, antibacterial, and animal-repellent activities. In addition to these effects, stress (especially heat stress)-tolerance-enhancing activities can be expected. Biostimulants containing such essential oils may be able to maintain the yield and quality of crops under increasing ambient temperatures. In this review, chemicals that enhance the heat tolerance of plants are designated as heat tolerance enhancers (HTLEs). Some essential oil compounds can be categorized as HTLEs available for biostimulants.