Understanding Rice-Magnaporthe Oryzae Interaction in Resistant and Susceptible Cultivars of Rice under Panicle Blast Infection Using a Time-Course Transcriptome Analysis

Abstract

Rice blast is a global threat to food security with up to 50% yield losses. Panicle blast is a more severe form of rice blast and the response of rice plant to leaf and panicle blast is distinct in different genotypes. To understand the specific response of rice in panicle blast, transcriptome analysis of blast resistant cultivar Tetep, and susceptible cultivar HP2216 was carried out using RNA-Seq approach after 48, 72 and 96 h of infection with Magnaporthe oryzae along with mock inoculation. Transcriptome data analysis of infected panicle tissues revealed that 3553 genes differentially expressed in HP2216 and 2491 genes in Tetep, which must be the responsible factor behind the differential disease response. The defense responsive genes are involved mainly in defense pathways namely, hormonal regulation, synthesis of reactive oxygen species, secondary metabolites and cell wall modification. The common differentially expressed genes in both the cultivars were defense responsive transcription factors, NBS-LRR genes, kinases, pathogenesis related genes and peroxidases. In Tetep, cell wall strengthening pathway represented by PMR5, dirigent, tubulin, cell wall proteins, chitinases, and proteases was found to be specifically enriched. Additionally, many novel genes having DOMON, VWF, and PCaP1 domains which are specific to cell membrane were highly expressed only in Tetep post infection, suggesting their role in panicle blast resistance. Thus, our study shows that panicle blast resistance is a complex phenomenon contributed by early defense response through ROS production and detoxification, MAPK and LRR signaling, accumulation of antimicrobial compounds and secondary metabolites, and cell wall strengthening to prevent the entry and spread of the fungi. The present investigation provided valuable candidate genes that can unravel the mechanisms of panicle blast resistance and help in the rice blast breeding program.

Genome-Wide Identification and Characterisation of Cytokinin-O-Glucosyltransferase (CGT) Genes of Rice Specific to Potential Pathogens

“…The proteins are determined to be predominantly hydrophilic (58.6%) due to exhibiting negative GRAVY values. Negative GRAVY score values indicate hydrophilic peptide sequences, whereas positive GRAVY scores indicate hydrophobic peptide sequences [ 45 ]. In predicting the subcellular localisation of the CGTs in the rice plant, the enzymes were distributed in the plastids (16), plasma membrane (13), mitochondria (5), and cytosol (4).…”

Identification and fine mapping of qPBR10-1, a novel locus controlling panicle blast resistance in Pigm-containing P/TGMS line

“…OsGF14b, a quantitatively blast resistance gene in rice, plays opposite roles in seedling blast and panicle blast resistance, appears to positively regulate the expression of genes involved in the auxin and jasmonic acid (JA) signaling pathway, accompanied by the reprogramming of the phenylpropanoid and diterpenoid pathways, but negatively regulate the expression of genes involved in the salicylic acid (SA) signaling pathway (Liu et al 2016;Yan et al 2020). Transcriptome analysis also identi ed a large number of genes were upregulated involved in detoxi cation, cell wall synthesis and modi cations pathway in panicle blast resistance, which were rarely reported in seedling blast resistance (Kumar et al 2021).…”

Meta‐analysis of transcriptomic studies of cytokinin‐treated rice roots defines a core set of cytokinin response genes

“…LOC_Os03g46860 is transcriptionally induced by rice blast ( Magnaporthae oryzae ) infection and is suppressed by NH 4 + (Kumar et al. , 2021; Wang et al. , 2017).…”