Interaction between sugarcane and Colletotrichum falcatum causing red rot: Understanding disease resistance at transcription level

Abstract

Detailed studies were taken up on host pathogen interaction between sugarcane and Colletotrichum falcatum causing red rot at the transcription level with a set of sugarcane varieties varying in disease resistance. A set of gene specific primers were designed to detect transcripts of resistance gene analogues (RGA’s), defense-related genes, transcription factors and signaling pathway genes induced during the host-pathogen interaction. mRNA extracted from pathogen inoculated canes at different time intervals were screened with 50 primers. Many of the transcripts were found to be expressed from the time of inoculation till 48h However, differential gene expression was found only for chitinase, metallothionein, R30 (RGA), receptor protein kinase, reversibly glycosylated protein and signal sequence hydrophobic region (SSHR) between resistant and susceptible varieties. Additionally differences in transcript size were noticed for some of the screened primers. We have standardized differential display (DD)-RT-PCR protocol with silver staining method to identify differential transcripts. Work on transcriptional variation in C. falcatum-sugarcane interaction has been performed for the first time and this promises a new approach to identify gene(s) involved in red rot resistance in sugarcane.