Detection of Rhynchosporium secalis in barley seeds through polymerase chain reaction technique (PCR)

O. RIOS, M.; FERNANDEZ, P.; CARMONA, M.

FITOPATOLOGIA BRASILEIRA

Sociedade Brasileira de Fitopatologia

Lugar: Brasilia; Año: 2008 vol. 32

0100-4158

Leaf scald of barley caused by Rhynchosporium secalis is an important disease in Argentina. The fungus is a necrotrophic pathogen which survives in stubble, seeds and weeds. Isolation of R. secalis from seeds on artificial media has not been successful due to the slow growing rate of the pathogen and strong inhibition by contaminants. The objective of this work was to detect R. secalis in different genotypes of barley seeds using the polymerase chain reaction (PCR)-based diagnostic assay. Four barley genotypes were tested in 2004: Quilmes Ayelén, Quilmes Alfa, Barke and Maltería Pampa 1004. The RS8 5’ (TTGTTTTTAGTGATGTCTGAG) 3’and RS9 5’ (AGGCACCGCCACTGATTTTAGGG) 3’ primers were selected. A 264-bp single band was obtained in each cultivar showing the presence of R. secalis. This study provides benefits over conventional methods for R. secalis detection and it would be useful in diagnosis, epidemiological and seed transmission studies. This is the first report on the detection of R. secalis in barley seeds in Argentina. Additional Keywords: Rhynchosporium secalis, barley seeds, diagnosis, PCR.