Green Leaf Volatile Profiling Reveals Ripening-Stage- and Tissue-Specific Patterns in Rosaceae Berries

Green leaf volatiles (GLVs) are key contributors to fruit aroma and plant defense, yet their accumulation during fruit ripening and across tissues remains understudied in Rosaceae berries. In this study, GLV profiles of the LOX-HPL pathway were compared between leaves, unripe, half-ripe, and ripe fruit of commercial strawberry (Fragaria × ananassa), raspberry (Rubus idaeus), blackberry (Rubus sp.), and woodland strawberry (Fragaria vesca) using HS-SPME-GC-MS. Eleven GLVs were identified, exhibiting strong species- and ripening-dependent variation. Odor activity value analysis showed that grassy aldehydes were the main predicted GLV contributors to aroma in ripe raspberry and blackberry samples, as opposed to fruity esters in ripe strawberry samples. However, differences in outdoor growth and harvest conditions should be considered when interpreting interspecies comparisons. Multivariate analyses suggest that GLVs may discriminate between ripening stages and reveal patterns of co-variation between (Z)-3-hexenal, (E,E)-2,4-hexadienal, and 4-oxohex-2-enal. Berry leaves contained substantially higher total GLVs and distinct compositions compared to fruit, such as the alcohol-rich profile of blackberry leaves, consistent with tissue- and species-associated differences in GLV profiles.