Pepper is planting widely in plastic houses and the fields; Botrytis cinerea infection starts in the field, but is
strongly appear during storage. Results revealed that spraying pepper plants under plastic houses condition with
salicylic, citric acids and clove or olive oils at different concentration (Salicylic acid at 8mM and citric acid at
30 Mm, meanwhile clove and olive oils at rate 5 m/l) reduced development of grey mold on fruits during cold
storage. The mycelial growth of B. cinerea was the most sensitive to salicylic acid, where it completely inhibited
the growth of tested fungus at concentrations 4 and 8 Mm. Clove and olive oils at their tested concentrations (2.5
and 5 m/l) reduced the growth of Botrytis cinerea to 100%. All tested plant oils and citric acid increased the
epidermis and cuticle thickness and decreasing simultaneously the disease infection incited by Botrytis cinerea on
pepper fruits. Spraying pepper plants with all tested treatments increased peroxidase and polyphenoloxidase
activities at 2 and 5 days from storage in naturally infected pepper fruits and at 5 days from storage in infected
fruits with B. cinerea. The total phenolic compounds (TPC) and antioxidant activity (2,2-Diphenyl-1-picrylhydrazyl
DPPH) were determined. Natural infection treated by clove 2.5 m/l had the highest content of TPC. The
high antioxidant activities of clove treated pepper fruits were attributed to its high contents of total phenolic
compounds.