Characterization and pathogenicity of Macrophomina phaseolina isolated from pine seedlings

Macrophomina phaseolina, an important soilborne pathogen, can cause significant economic losses in many cultivated crops. The fungus is often found in forest nurseries along with many other fungi associated with seedling mortality in both broad-leaved and coniferous forest tree species. In this thesis study, the prevalence of Macrophomina phaseolina in Pinus brutia Ten. (Turkish Red Pine) and Pinus pinea L. (Stone Pine) seedlings in the Osmaniye forest nursery was investigated. Symptomatic, apparently healthy, and dead seedlings of both Turkish Red Pine and Stone Pine were sampled from the diseased seedbeds. More than half of the obtained isolates were identified as M. phaseolina. M. phaseolina was isolated from 50.4% of the seedlings, with a higher frequency in P. pinea (65.0%) compared to P. brutia (40.5%). The isolation rates were highest in dead seedlings (61.8%), followed by symptomatic ones (56.0%).