Improving drought tolerance in rice: Ensuring food security through multi‐dimensional approaches

Abstract

Drought has been highly prevalent around the world especially in Sub-Saharan Africa and South-East Asian countries. Consistent climatic instabilities and unpredictable rainfall patterns are further worsening the situation. Rice is a C 3 staple cereal and an important food crop for the majority of the world's population and drought stress is one of the major growth retarding threats for rice that slashes down grain quality and yield. Drought deteriorates rice productivity and induces various acclimation responses that aids in stress mitigation. However, the complexity of traits associated with drought tolerance has made the understanding of drought stress-induced responses in rice a challenging process. An integrative understanding based on physiological adaptations, omics, transgenic and molecular breeding approaches successively backed up to developing drought stress-tolerant rice. The review represents a step forward to develop drought-resilient rice plants by exploiting the knowledge that collaborates with omics-based developments with integrative efforts to ensure the compilation of all the possible strategies undertaken to develop drought stresstolerant rice. | INTRODUCTIONClimatic fluctuations in recent decades have been escalating the frequency and extremity of calamities in many parts of the world. More than 83% of the detrimental effects caused by drought occur in the agricultural sector that leads to crop loss and limited productivity, affecting food supplies and livelihood of people and has emerged as the most serious famines inducing factor across the globe (FAO, 2018). Rice is one of the major cereals and its consumption comprises over 27% of total cereal utilisation with an output of 738.2 million tons globally (FAO, 2016). Rice is a paddy field crop with more water requirement for growth and thus drought stress is considered as the major inimical that hinders rice growth, productivity and yield (Mumtaz et al., 2020).Drought stress detrimentally affects rice production by deteriorating everything from seed germination to the reproductive stages

Imperative role of sugar signaling and transport during drought stress responses in plants

“…The free hydroxyl groups of soluble sugars compensate that of water to maintain the protein structure and function as well as the hydrophilic interactions in the cell membrane (Poonam et al, 2016). Drought also incites the plant root system to take up the available water more efficiently and causes an increase in the root‐shoot ratio, which is invariably facilitated by transportation and accumulation of soluble sugars in the roots (Khan, Palakolanu, et al, 2020). Additionally, Du et al (2020) showed that increased sugar metabolism, transport, and distribution caused greater root‐shoot ratio, thereby enhancing drought tolerance.…”

Towards Developing Drought-smart Soybeans

“…Genetic engineering approaches offer viable opportunities for accelerated crop improvement (Khan et al, 2020;Lohani et al, 2020;Arya et al, 2021). Genes controlling traits, such as flowering time, disease resistance and lipid profile, have been identified and used as targets for soybean improvement (Haun et al, 2014;Arya et al, 2018;Ngaki et al, 2021).…”

Salicylic Acid Increases Photosynthesis of Drought Grown Mustard Plants Effectively with Sufficient-N via Regulation of Ethylene, ABA and Nitrogen-Use Efficiency

“…It can become chronic in climatic regions with limited water resources or in areas where rainfall is erratic (Tian and Lie 2006;Nawaz et al 2014;Khan et al 2020;Sehar et al 2020;Seleiman et al 2021).…”

“…It is noteworthy that hormonal signals crosstalk under drought condition (Khan et al 2020) may cooperate to govern drought stress responses , such as ethylene and ABA accumulation regulate many developmental processes and adaptive stress responses (Nazar et al 2015;Sehar et al 2020;Takahashi et al 2020). Drought stress rapidly induces the expression of 9-cis-epoxycarotenoid dioxygenase 3 (NCED3), which is important in ABA synthesis (Behnam et al 2013).…”