Molecular Microbiology Research 2024, Vol.14, No.5, 236-247 http://microbescipublisher.com/index.php/mmr 243 root biomass at moderate salinity levels. The study concluded that the interaction of rice with these specialized microbiota forms the composition of the rhizosphere microbiota, which supports the growth of plants under salt stress (Santos et al., 2021). In addition, the role of SST gene in rice is also related to rhizosphere bacterial community and soil metabolites. The study found that the presence of SSTgenes significantly affected rhizosphere bacterial communities and soil metabolites, thereby enhancing rice tolerance to high salt levels (Lian et al., 2020). Figure 3 Effect of inoculation of Halotolerant endophytes and rhizobacteria on two rice varieties (A) CO51, and (B) Pusa Basmati 1. Sequence of pots from left to right (in both of the figures): T1 = Negative control, T2 = Positive control (200 mM NaCl), T3 = 200 mMNaCl + Trichoderma viride, T4 = 200 mM NaCl + Bacillus haynesii 2P2, T5 = 200 mM NaCl + Bacillus safensis BTL5, T6 = 200 mM NaCl +Brevibacterium frigoritolerans W19, and T7 = 200 mM NaCl +Pseudomonas fluorescens 5.3 Role of microbes in enhancing rice resistance to pathogens Microbes also play a crucial role in enhancing rice resistance to pathogens. The inoculation of rice plants with beneficial rhizobacteria has been shown to induce systemic resistance against various pathogens. For example, the application of a consortium of rhizobacteria not only improved drought tolerance but also enhanced the overall health of rice plants, potentially providing resistance against opportunistic infections (Kakar et al., 2016). Additionally, the restructuring of root-associated microbiomes under drought stress is found to include shifts in microbial communities that can provide protection from pathogenic microbes. The enrichment of specific bacterial taxa under drought conditions suggests that these microbes might contribute to both abiotic and biotic stress tolerance (Santos-Medellín et al., 2021). The synergistic roles of roots and rhizosphere microbes are pivotal in enhancing rice stress tolerance. The integration of beneficial microbes into rice cultivation practices offers a promising strategy to mitigate the adverse effects of drought, salinity, and pathogen attacks, thereby contributing to sustainable agriculture. 6 Biotechnological and Agronomic Approaches 6.1 Genetic engineering of rice for enhanced root-microbe interactions Genetic engineering offers a promising avenue to enhance root-microbe interactions in rice, thereby improving stress tolerance. One approach involves manipulating specific genes that influence the rhizosphere microbiome. For instance, the squamosa promoter binding protein box (SBP box) family gene (SST/OsSPL10) in rice has been shown to affect the rhizosphere bacterial community and soil metabolites, which are crucial for salt stress tolerance. CRISPR-edited lines with altered SST function demonstrated significant changes in rhizobacterial assembly and soil metabolite profiles, leading to improved salt stress adaptation (Lian et al., 2020). Additionally, breeding strategies that promote beneficial plant-microbiome interactions, such as selecting for traits that enhance root exudate profiles, can further optimize these interactions (Yang et al., 2023). 6.2 Application of beneficial microbial inoculants The application of beneficial microbial inoculants, such as PGPR and mycorrhizal fungi, has been extensively studied for their role in enhancing rice stress tolerance. PGPR, including Bacillus amyloliquefaciens and Aspergillus spinulosporus, have been shown to prime rice plants for improved defense against pathogens like
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