Phytotoxic volatile compounds from Pinus halepensis resin associated with Lophodermium sp. Chemical and biological insights

The resin of Pinus halepensis, a natural exudate from Aleppo pine, was analyzed to identify its volatile compounds and evaluate its phytotoxic activity. The resin appeared creamy white and solid, turning into a fine powder when ground. Molecular identification confirmed the presence of the endophytic fungus Lophodermium sp., with its ITS sequence deposited in GenBank (accession number PX393054), suggesting a possible role in shaping the resin's chemical profile. SPME-GC-MS analysis showed that the main volatile compounds were 2,5-furandione, 3-dodecenyl (52.2 %) and 2,5-di-tert-butylphenol (18.4 %), along with various alkanes and methylated hydrocarbons, representing over 99 % of total volatiles. Phytotoxicity tests revealed strong inhibitory effects on plant tissues and seedling growth, indicating the resin contains bioactive volatiles affecting plant development. These findings demonstrate the phytotoxic potential of P. halepensis resin, while further studies are required to elucidate the specific role of associated endophytic fungus.