Genetic Diversity of Puccinia polysora in Thailand based on Inter Simple Sequence Repeat (ISSR) markers analysis

Abstract

Corn rust fungi are considered as major pathogens in corn production of Thailand. Two corn rust species, Puccinia polysora (southern rust) and P. sorghi (common rust) which are different in their life cycles and preferred environment have been reported in Thailand. In this study, genetic diversity of southern rust from various locations of corn plantation in Thailand was investigated. The genetic diversity of corn rust was analyzed using PCR amplification of inter simple sequence repeat (ISSR) region. Morphological-based identification determined that all of the rust specimens were P. polysora. A high variety of 38 polymorphic bands were found from the specimens by PCR amplification using five primers: GAG (TCG)5, GAG (CGA)5, (CGA)5, (GTC)5 and (CAG)5. These bands were used to construct UPGMA dendogram, which cluster analysis divided the 38 specimens into 13 groups at 75% Dice’s similarity coefficient with cophenetic correlation (r) =0.826. The isolates from different localities are presented in the same groups, supporting that P. polysora from different provinces in Thailand are expressed genetic characteristic that resulted from the spore migration.