Stress Memory and Priming Applications in Plants: Potential for Breeders

Abstract

Humankind interfered in the natural selection of plants in favor of traits such as yield, grain quality, productivity, and flavor principally at the expense of several biotic and abiotic stress tolerance capacities. Plants are subjected to the detrimental effects of the combination of these factors due to their stationary nature. Today, there are various breeding approaches from classical to transgenesis and even genome editing to tame plant genome for our purposes. Additionally, the significance of epigenetic regulation in response to biotic and abiotic stresses has been recognized in the last decade. Acquisition and preservation of stress memory for the progeny to allow them to adapt to similar conditions through methylation, histone modification, and chromatin structure alterations are the focus of attention. Enlightening the cross talk between these components of acquired transgenerational memory may aid to breed more efficient and environmentally friendly crops in current agricultural systems. Priming applications have been extensively studied to induce stress memory of the plant by external stimulus as a warning signal, which may ignite minor activations of stress-responsive gene expression and eventually turn into strong resistance. The present chapter will discuss the basis and the recent advances in plant epigenetic regulation with emphasis on chemical, biotic, and abiotic priming agents.