Coping with inclement weather conditions due to high temperature and water deficit in rice: An insight from genetic and biochemical perspectives

Abstract

Climatic fluctuations, temperature extremes, and water scarcity are becoming increasingly unpredictable with the passage of time. Such environmental atrocities have been the scourge of agriculture over the ages, bringing with them poor harvests and threat of famine. Rice production, owing to its high-water requirement for cultivation, is highly vulnerable to the threat of changing climate, particularly prolonged drought and high temperature, individually or in combination. Amidst all the abiotic stresses, heat and drought are considered as the most important concurrent stressors, largely affecting rice yield and productivity under the current scenario. Such threats heighten the need for new breeding and cultivation strategies in generating abiotic stress-resilient rice varieties with better yield potential. Responses of rice to these stresses can be categorized at the morphological, physiological and biochemical levels. This review examines the physiological and molecular mechanism, in the form of up regulation of several defense machineries of rice varieties to cope with drought stress (DS), high temperature stress (HTS), and their combination (DS-HTS). Genotypic differences among rice varieties in their tolerance ability have also been addressed. The review also appraises research studies conducted in rice regarding various phenotypic traits, genetic loci and response mechanisms to stress conditions to help craft new breeding strategies for improved tolerance to DS and HTS, singly or in combination. The review also encompasses the gene regulatory networks and transcription factors, and their cross-talks in mediating tolerance to such stresses. Understanding the epigenetic regulation, involving DNA methylation and histone modification during such hostile situations, will also play a crucial role in our comprehensive understanding of combinatorial stress responses. Taken together, this review consolidates current research and available information on promising rice cultivars with desirable traits as well as advocates synergistic and complementary approaches in molecular and systems biology to develop new rice breeds that favorably respond to DS-HTS-induced abiotic stress.

The era of cultivating smart rice with high light efficiency and heat tolerance has come of age

“…At present, a large number of heat resistance related genes have been identified, which has provided some help for heat resistance breeding of rice. However, the number of successfully cloned genes is very limited (Table 1) (Rabara et al, 2021). Therefore, it is still the focus of rice heat tolerance research to successfully clone the identified heat tolerance genes and make them be used in breeding practice.…”

“…This undoubtedly provides a new channel for breeding rice with heat tolerance. However, although many heat tolerance related regulatory loci and QTLs have been reported, these studies cannot further improve rice yield (Khan et al, 2019;Rabara et al, 2021). In other words, these studies can only guarantee the stability of rice yield under various high temperature conditions.…”

Amylose Accumulation Under Water Deficit in Glutinous Rice (Oryza sativa L. Var. glutinosa)

“…Inconsistent starch content is thought to be affected by differences in glutinous rice varieties' response, which is assumed by differences in gene expression. Based on the research results by Rabara et al (2021), each variety has different genetic, morphological, and physiological characteristics. Different types of rice can affect diversity; thus, it affects starch metabolism and accumulation.…”

Identification and Evaluation of Regulatory Role of miR164b in Malaysian Rice Variety (MR303) under Drought Stress

“…The phenomenon affects the regularity and number of hydrological fluctuations, particularly in developing nations. Drought stress has been identified as a major threat to rice production [3].…”