Identification and expression analysis of pathogenicity-related genes of anastomosis groups infecting rice.

UNLABELLED

Sheath blight disease caused by Kuhn (teleomorph; ) is a major constraint in rice production. Among the different anastomosis groups (AGs) of , AG1-IA causes sheath blight of rice, which induce necrotic lesions on leaf sheaths of the infected plants. Several reports contradict the host specificity of anastomosis groups in . There is lack of information on the pathogenicity genes of these anastomosis groups during sheath blight infection in rice. In the present study, isolates collected from diverse rice growing regions of India were screened for anastomosis groups and two groups namely, AG1-IA, AG2-2 were identified. Accordingly, comparative studies were made with AG1-IA (GenBank ID: 16,395) and AG2-2 (GenBank ID: 2,318,768) group sequences, which enabled the identification of specific gene clusters (119 in AG1-IA and 604 in AG2-2) belonging to these groups. Pathogen Host Interaction (PHI) blast with these specific gene clusters could further identify genes involved in host pathogen interaction (38 in AG1_IA and 150 in AG2-2), which were shortlisted for qRT-PCR validation based on qcov cutoff values representing different phenotypic categories of PHI blast. Expression analysis-based validation in sheath blight susceptible (Pusa Basmati 1) and resistant (Pusa 1908-13-12-5) rice genotypes showed that most of the genes expressed significantly higher in the susceptible variety Pusa Basmati 1. The genes like inorganic phosphate transporter (), Bromodomain containing protein (), Aldehyde dehydrogenase (), AMP binding domain () and Heme peroxidase () were upregulated in the susceptible genotype, PB 1 at 72hpi compared to Pusa 1908-13-12-5. Among these, inorganic phosphate transporter (), Bromodomain containing protein () and Heme peroxidase () were specific to AG1-IA. Through the present study, we could demonstrate the AG1-IA-specific interactions of causing sheath blight disease of rice, which is a step forward in understanding the specificity of with reference to sheath blight disease of rice.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13205-021-02934-1.