Ch. Crisosto et al., INCIDENCE OF PHYSICAL DAMAGE ON PEACH AND NECTARINE SKIN DISCOLORATION DEVELOPMENT - ANATOMICAL STUDIES, Journal of the American Society for Horticultural Science, 118(6), 1993, pp. 796-800
Skin discoloration (SD) formation in peach [Prunus persica (L.) Batsch
] and nectarine [Prunus persica (L.) Batsch, var. nectarine]was relate
d to physical damage (abrasion) to the fruit during fruit handling (ha
rvest and hauling operations) within the orchard and during transport
to the packinghouse. Vibration and rubbing treatments increased SD for
mation indicating that tissue damage is involved in SD formation. Anat
omical studies comparing sound and SD-injured tissues done by scanning
electron and light microscopy indicated that very-low-intensity physi
cal damage could induce brown and/or black spots because of cell disru
ption in the epidermal and hypodermal layers. The fact that injury was
specific to the exocarp tissues (cuticle, epidermis, and hypodermis),
and that mesocarp tissue located below the exocarp cells remained sou
nd and turgid, indicated that abrasion injury is associated with SD. S
imilar types of visible and anatomical injury characteristics were ind
uced by a rubbing treatment, demonstrating that physical abrasion dama
ge affecting just exocarp cells was enough to induce SD.