Brown Spot

(Alternaria passiflorae)

Credits: Biovision-Infonet

The most important disease worldwide is brown spot on leaves, vines and fruits.

Symptoms are brown spots, up to 10 mm diameter, on the leaves, often extending along the veins and drying out in the centre.

On the stems, spots are up to 30 mm long, and when they occur at the leaf axils may kill the vine, resulting in dieback.

On the fruit, the spots are light brown, round and sunken; they often merge, covering large areas, and produce red-brown spore masses.

Spores, produced on the leaf, stem and fruit, are dispersed by wind-blown rain. Warm, moist weather favours disease development. (EcoPort)

What to do:

• Yellow passion fruit and its hybrids are more tolerant to this disease.
• Field sanitation (collection and disposal of fallen diseased fruits, leaves and vines).
• Pruning vines to reduce density and thereby reducing humidity within the crop. It also facilitate better air circulation, light and spray penetration and cover.
• Timely sprays with copper based fungicides. During humid weather, when the vines are growing rapidly, reduce the intervals between spray applications to 2 or 3 weeks to ensure that new growth is adequately protected.