Rice blast disease is widespread throughout Thai rice fields, especially in those planted to well-known cultivar KDML105. This disease is caused by an ascospore fungus, Pyricularia grisea (anamorph ...Magnaporthe grisea). Many methods have been applied in DNA fingerprinting of the Thai P. grisea, including random amplified polymorphic DNA (RAPD). The RAPD pattern of some rice-host isolates had revealed diversity in different cultivars. The other method used to study fingerprinting pattern is AFLP (amplified fragment length polymorphism). A small-scale cluster based on this method differed from the cluster from the RAPD technique. However, this technique can be used to separate barley isolates from rice isolates. These selected methods were used in determining diversity in Thai P. grisea populations. The cluster characterized by its genetics will be compared with cluster data obtained by pathotyping.
Rice blast, caused by Pyricularia grisea, is one of the major diseases affecting rice yields in Thailand. We are analyzing the virulence spectrum and genetic structure of the Thai blast pathogen ...population. In this study, we present results for 29 isolates collected from different rice-growing regions in Thailand. Genetic diversity was assessed by random amplified polymorphic DNA (RAPD) analysis and virulence patterns were determined by spray-inoculating more than 50 rice cultivars carrying different resistance genes, including Thai rice cultivars, with each isolate. Cluster analysis of molecular band profiles grouped the isolates in five groups sharing 80% or a higher percentage of band similarity. The isolates showed a diversity of (a)virulence patterns, and only two of the isolates tested showed an identical pattern. We conclude that there is a high degree of pathotype diversity among Thai isolates of the rice blast pathogen. Resistant reactions were more common than susceptible reactions to each of the individual isolates. There was no clear overall agreement between the molecular profile of isolates and their virulence pattern. However, a few cultivars showed RAPD group-specific (a)virulence.
Blast disease, caused by Pyricularia grisea, is one of the most serious diseases of rice in Thailand. To study the diversity in this fungus, rice samples showing blast symptoms on the leaf, neck, ...collar, panicle, and seed were collected from rice fields in various locations in Thailand. During the collection, it was observed that the popular cultivars grown by farmers, KDML105 and sticky rice, had high disease severity, especially in northern and northeastern Thailand. Several cultivars, such as Hom Klong Laung and Hom Suphan, were highly resistant in some locations byt susceptible in others. In addition to differences in cultural characteristics of Pyricularia grisea between isolates, we found high diversity in spore morphology among isolates from different locations. Moreover, results of the pathotype test indicated that many isolates were compatible with different cultivars. When examined for mating type, results showed 123 blast isolates of type I and 21 of type II.
AFLP analysis of blast pathogen diversity in Thailand Pilaiwan Hutamekalin(National Science and Technology Development Agency, Bangkok (Thailand). National Center for Genetic Engineering and Biotechnology); Thanaporn Veerapraditsin(National Science and Technology Development Agency, Bangkok (Thailand). National Center for Genetic Engineering and Biotechnology); Suchada Pimpisitthavorn(National Science and Technology Development Agency, Bangkok (Thailand). National Center for Genetic Engineering and Biotechnology) ...
2001
Conference Proceeding
Relation of Pi-genes cultivars with Thai rice cultivar Tanee Sreewongchai(National Science and Technology Development Agency, Bangkok (Thailand). National Center for Genetic Engineering and Biotechnology); Saengchai Sriprakhon(National Science and Technology Development Agency, Bangkok (Thailand). National Center for Genetic Engineering and Biotechnology); Suchada Pimpisitthavorn(National Science and Technology Development Agency, Bangkok (Thailand). National Center for Genetic Engineering and Biotechnology) ...
2001
Conference Proceeding
Studies inhibition of appressorium formation of Thai blast fungal Suchada Pimpisitthavorn(National Science and Technology Development Agency, Bangkok (Thailand). National Center for Genetic Engineering and Biotechnology); Thanee Sreewongchai(Chitralada palace, Bangkok (Thailand). Plant Genetic Conservation Project); Sermsiri Mayteeworakoon(National Science and Technology Development Agency, Bangkok (Thailand). National Center for Genetic Engineering and Biotechnology) ...
2001
Conference Proceeding
Fertility and mating type of Magnaporthe grisea rice pathogen in Thailand Saengchai Sriprakhon(National Science and Technology Development Agency, Bangkok (Thailand). National Center for Genetic Engineering and Biotechnology); Eduard Roumen(Jozef Plateaustraat 22, Gent (Belgium). Aventis CropScience); Arunee Surin(Pension official of Department of Agriculture, Bangkok (Thailand)) ...
2001
Conference Proceeding
Distribution of blast pathogen in Thailand related with pathogenicity on rice Sermsiri Mayteeworakoon(National Science and Technology Development Agency, Bangkok (Thailand). National Center for Genetic Engineering and Biotechnology); Thanee Sriwongchai(Chitralada Palace, Bangkok (Thailand). Plant Genetics Conservation Project); Saengchai Sripracone(National Science and Technology Development Agency, Bangkok (Thailand). National Center for Genetic Engineering and Biotechnology) ...
2001
Conference Proceeding
