Post Harvest Diseases

a. Rhizopus Rot (R. stolanifer)

• Water soaked lesion which exude a clear liquid.
• Lesion surface may be covered with thin, cotton-like fungal structure (Especially under humid condition)
• Tissue within the lesion are usually held together by relatively coarse strands of fungal hyphae.
• Dark sporulation may crown the white tuft of

b. Gray mold (Botrytis cinerea)

• Watery lesion area with a light brown or tan-colored central region which contain dark-brown specks.
• Covered into a soft, watery mass within a few days.
• Skin is broken, the grayish mycelium and spore clusters develop within a few hours.

c. Black rot (Physalospora obtuse)

• larger brown, dead but firm areas

d. Blue mold (Penicillium expansum)

• watery spots
• The decayed portions are sharply separated from the healthy tissues
• The spots range in color from brown to pale straw
• Show all possible variations in size

e. Anthracnose (Colletotrichum acutatum)

• water soaked lesions up to 3 mm in diameter
• Infected fruit eventually dry down to form hard, black, shriveled mummies.

f. Stem end rot (Phomopsis sp.)

• Water soaked areas Brown to black color.

g. Sour rot (Colletotrichum candidum)

• Symptoms include a soft watery rot with leakage of berry juice, and a distinctive vinegar smell

h. Fusarium rot (Fusarium spp)

• graminum, F. acuminatum, F. culmorum, and F. moniliforme produce a distinct reddish or purplish pigmentation in the diseased area
• semitectum, F. equiseti, F. scirpi, and F. solani produce brown internal lesions; a cross section of a mature lesion reveals a dry, brown, spongy rot.

i. Wet rot ( Choanephora cucurbitarum )

• Fruits rot rapidly and white fungal mold appears on the infected area
• the heads are white to brown but turn purplish-black within a few days
• water-soaked and soft
• An entire fruit can rot in a 24-to-48-hour period
• Symptoms usually begin on the blossom end of the fruit.

j. Brown rot ( Monilinia fructicola)

• first appears as small, circular brown spots that increase rapidly in size
• Infected fruit eventually turn into shriveled, black mummies that may drop or remain attached to the tree through the winter.
• Brown rot can be serious on injured fruit such as cherries split by rain.

k. Alternaria rot ( Alternaria spp.)

• more or less round, brown to black lesions
• weakened tissue

l. Bacterial soft rot ( Erwinia carotovora)

• softening and water soaking
• yellow initially, turning brown as the disease
• these organisms generally appear just before or at the time of harvest or in storage.