Exploration of Epigenetics for Improvement of Drought and Other Stress Resistance in Crops: A Review

Abstract

Crop plants often have challenges of biotic and abiotic stresses, and they adapt sophisticated ways to acclimate and cope with these through the expression of specific genes. Changes in chromatin, histone, and DNA mostly serve the purpose of combating challenges and ensuring the survival of plants in stressful environments. Epigenetic changes, due to environmental stress, enable plants to remember a past stress event in order to deal with such challenges in the future. This heritable memory, called “plant stress memory”, enables plants to respond against stresses in a better and efficient way, not only for the current plant in prevailing situations but also for future generations. Development of stress resistance in plants for increasing the yield potential and stability has always been a traditional objective of breeders for crop improvement through integrated breeding approaches. The application of epigenetics for improvements in complex traits in tetraploid and some other field crops has been unclear. An improved understanding of epigenetics and stress memory applications will contribute to the development of strategies to incorporate them into breeding for complex agronomic traits. The insight in the application of novel plant breeding techniques (NPBTs) has opened a new plethora of options among plant scientists to develop germplasms for stress tolerance. This review summarizes and discusses plant stress memory at the intergenerational and transgenerational levels, mechanisms involved in stress memory, exploitation of induced and natural epigenetic changes, and genome editing technologies with their future possible applications, in the breeding of crops for abiotic stress tolerance to increase the yield for zero hunger goals achievement on a sustainable basis in the changing climatic era.

Physiological and Epigenetic Reaction of Barley (Hordeum vulgare L.) to the Foliar Application of Silicon under Soil Salinity Conditions

“…The memory of a specific environmental stress ability of plants is called 'plant memory' or 'epigenetic memory'. This memory provides a smart basis for a strong and quick response to such future stress challenges [128].…”

Activating stress memory: eustressors as potential tools for plant breeding

“…To date the understanding and application of epigenetic and stress memory in breeding strategies are limited, but they have a great potential for improving crop varieties through the production of new epialleles to controlling gene expression during development in response to the environmental pressure (Kakoulidou et al 2021 ; Sun et al 2021 ). There are still challenges to reach regarding the use of stressor for fix characters of interest through memory, as plant and conditions specific protocols based on desirable goals, such that further research needs to be performed to elucidate the missing gaps to design suitable strategies, opening new fields of research as the primeomics (Srivastava et al 2021 ).…”

Omics-Facilitated Crop Improvement for Climate Resilience and Superior Nutritive Value

“…These epigenetic modifications are instituted to modulate spatio-temporal gene expressions in response to external stimuli or specific developmental requirements ( Yuan et al, 2013 ; Singh and Prasad, 2021 ). More crucially, these epigenetic alterations involve the development of internal memory marks which assist plants to adapt to several abiotic and biotic stresses via physiological regulation directed by plants‘ epigenetic history (reviewed in Samantara et al, 2021 ; Sun et al, 2021 ). The molecular mechanisms underpinning plant environmental stress responses often rely on these epigenetic modifications (for extensive reviews, see Kim et al, 2010 ; Kim et al, 2015 ; Banerjee et al, 2017 ; Chang et al, 2020 ).…”