Seedling‐stage salinity tolerance in rice: Decoding the role of transcription factors

Abstract

Rice is an important staple food crop that feeds over half of the human population, particularly in developing countries. Increasing salinity is a major challenge for continuing rice production. Though rice is affected by salinity at all the developmental stages, it is most sensitive at the early seedling stage. The yield thus depends on how many seedlings can withstand saline water at the stage of transplantation, especially in coastal farms. The rapid development of “omics” approaches has assisted researchers in identifying biological molecules that are responsive to salt stress. Several salinity‐responsive quantitative trait loci (QTL) contributing to salinity tolerance have been identified and validated, making it essential to narrow down the search for the key genes within QTLs. Owing to the impressive progress of molecular tools, it is now clear that the response of plants toward salinity is highly complex, involving multiple genes, with a specific role assigned to the repertoire of transcription factors (TF). Targeting the TFs for improving salinity tolerance can have an inbuilt advantage of influencing multiple downstream genes, which in turn can contribute toward tolerance to multiple stresses. This is the first comparative study for TF‐driven salinity tolerance in contrasting rice cultivars at the seedling stage that shows how tolerant genotypes behave differently than sensitive ones in terms of stress tolerance. Understanding the complexity of salt‐responsive TF networks at the seedling stage will be helpful to alleviate crop resilience and prevent crop damage at an early growth stage in rice.

Pokkali: A Naturally Evolved Salt-Tolerant Rice Shows a Distinguished Set of lncRNAs Possibly Contributing to the Tolerant Phenotype

“…ERF, MYB, bZIP, and WRKY are known for their contribution to stress tolerance [33]; their association with lncRNA showed their involvement in TFs-driven stress tolerance. A recently-published review by Tiwari et al [34] also reported the involvement of these TFs in salinity tolerance, particularly in the contrasting rice genotypes used in the present study.…”

Plant growth-promoting rhizobacteria: Salt stress alleviators to improve crop productivity for sustainable agriculture development

“…Rhizospheric microbiomes heavily colonize the plant roots due to the availability of a nutrient-enriched biosphere comprising amino acids, carbohydrates, fatty acids, and organic acids acting as a passageway for the attraction of multiple microorganisms that thrive in this rhizosphere by utilizing root exudates. This dynamic zone around roots facilitates the microbial synthesis of compatible solutes, enzymes such as 1-aminocyclopropane-1-carboxylate (ACC) deaminase, and cell wall-degrading enzymes ions, as well as other secondary metabolites including phyto-hormones such as auxins, cytokinins, gibberellins, and ethylene, which augment plant growth and defense system under saline stress conditions ( Figure 4 ) ( Tiwari et al., 2022 ). Microbes reduce stress in plants by controlling nutritional and hormonal equilibrium and inducing systemic tolerance to stress ( Table 1 ) ( Kumawat et al., 2022c ).…”

Raising crops for dry and saline lands: Challenges and the way forward

“…The mechanisms of hydrogen sulfide‐mediated alleviation of salinity tolerance signaling cross talk with other signaling pathways are considered in the review by Srivastava et al (2022), while Verma et al (2022) discuss the literature concerning the role of AUXIN RESPONSE FACTORS (ARFs) in auxin‐mediated drought and salinity stress response. The approaches that have been used to identify the transcription factors with a potential role in salinity stress tolerance are presented in the review by Tiwari et al (2022), which also discusses the functions of key transcription factors families such as AP2/EREBP, bZIP, NAC, WRKY, MYB, and zinc finger proteins, in salinity tolerance in rice seedlings.…”