Identification of main pathogenic Fusarium species for biological control of poppy plants in Afghanistan

Afghanistan is one of the major countries which contributes to illegal poppy (Papaver somniferum L.) cultivation, globally. The objectives of the present study were to report the Fusarium species associated with P. somniferum and to investigate a potential biocontrol agent against P. somniferum. A total of 155 Fusarium isolates were obtained from four provinces in Afghanistan, including Helmand, Kandahar, Daikundi and Bamyan. The pathogenic Fusarium spp. isolates were characterized by morphological and molecular identification, using the translation elongation factor-1α (TEF-1α) gene. The results of isolation revealed the most predominant species as F. proliferatum (27%), followed by F. equiseti (26%), F. solani (13%), F. incarnatum (12%), F. acuminatum (7%), F. oxysporum (5%), F. verticillioides (5%), F. pseudograminearum (2%) and F. coeruleum (2%). With the exception of F. oxysporum and F. solani, other identified species are the first reported Fusarium species associated with poppy plants in Afghanistan. Furthermore, pathogenicity testing of F. oxysporum, F. proliferatum, F. acuminatum and F. verticillioides isolates were performed. Although disease symptoms were observed in all species; F. oxysporum infected poppy samples showed an early development of wilt symptoms and their disease severity was significantly higher than all other isolates. The results suggest that F. oxysporum isolates have the potential to be used as biological control agents against poppy plants in Afghanistan.