Abstract
Fusarium culmorum causing seedling and head blight on barley is associated with economic losses of crop yield and quality. Root lesion nematodes (Pratylenchusspp.) are important pests in cereal production worldwide. If these two organisms can often be found together on barley, their relationship is unknown. In this study reports the interaction of 12 F. culmorum isolates and one Pratylenchus thornei isolate on four barley varieties with simultaneous inoculation. After 8 weeks, barley varieties were evaluated according to disease severity and nematode reproduction rate. Barley varieties were found susceptible to F. culmorum isolates but their aggressiveness is different. The highest disease severity was found in the K17 and CAV6 isolates. Increases in disease severity were found to be significant in G14, YLVC16 and SK20 isolates in simultaneous inoculation. While the reproduction rate was higher when P. thornei was inoculated together with YOVA27 and K17 isolates, the reproduction rate was lower when inoculated simultaneously with 9 other isolates except YOVA21 and YLVC16. More negative interactions of F. culmorumisolates on P. thornei were detected in simultaneous inoculations. Differences between only nematode application and simultaneous application in the reproduction rate parameter were detected in Tarm92 and Tosunpaşa barley varieties.