Genetic Relationships of Curvularia lunata Races Causing Rice Dirty Panicle by ITS rDNA Sequence Analysis and ISSR Markers

Abstract

The rice dirty panicle disease is the main problem for rice production in Thailand. Rice dirty panicle is caused by six fungal pathogens of which Curvularia lunata was established to be the major pathogen in previous research. The purpose of this study was to examine the genetic relationships of C. lunata in Thailand using ITS rDNA sequence analysis and ISSR markers. The results revealed that C. lunata was grouped with C. lunata from the NCBI database with a 100% bootstrap support. The genetic data of 40 isolates of C. lunata were variable and diversity was detected within and among populations by ISSR markers. Multiple ISSR band profiles can be observed throughout Thailand and there are more than one band profile distributed in any given geographical location. However, certain band profiles are observed in only some geographical areas. These results support genotypic flow in C. lunata which is genetically diverse and distributed in different geographical areas in the country.