Monthly Archives: February 2020

Cucumber mosaic virus

Credits:Biovision-Infonet It is not seed transmitted except through seed of perennial wild cucumber (Echinocytis lobata) and chickweed (Stellaria media). It is mechanically transmitted and in nature it is spread by various species of aphids. It has a very extensive host range including such varied species as bananas, carrots, cowpeas, lupine, lilies, onions, passion fruit, potatoes […]

Viral diseases

Credits:Biovision-Infonet Many important virus diseases affect cucurbits. These include: Cucumber mosaic cucumovirus (CMV) Watermelon mosaic 2 potyvirus (WMV-2) Watermelon mosaic 1 potyvirus Zucchini yellow mosaic potyvirus (ZYMV) Squash leaf curl bigeminivirus (SLCV) What to do: Use tolerant / or resistant varieties if available. Remove infected plants (disinfect hands and tools with 70% alcohol after contact with infected […]

Passion Fruit Woodiness Potyvirus (PWV)

Credits: Biovision-Infonet A number of virus diseases have been reported, notably the passion fruit woodiness potyvirus. Affected leaves show light and dark green mosaic pattern often with light yellow speckle. Sometimes small, yellow ring spots may develop on upper leaf surface. Infected fruits are small and misshapen with very hard rind and small pulp cavity. […]

Scab

Cladosporium cucumerinum Credits:Biovision-Infonet It attacks all aboveground plant parts. Initial symptoms on leaves appear as light water-soaked or pale green spots. The spots are numerous and can appear on and between veins. Elongate spots may develop on petioles and stems. The spots later turn grey to white and become angular. The fine veinlets in the […]

Phytophthora Blight

(Phytophthora nicotianae var. parastica) Credits: Biovision-Infonet Affected leaves are water-soaked and light-brown in colour. They fall readily, leading to defoliation of the vines. Affected areas of the stem are first purple and later brown above the graft union. They may completely girdle the stem causing wilting and collapse of the vine. Fruit symptoms comprise of […]

Passion Fruit Fusarium Wilt

(Fusarium oxysporum f.sp. passiflorae) Credits: Biovision-Infonet Fusarium wilt (also called collar rot) symptoms consist of yellowing of leaves, the collar region of affected plant at soil level turns brownish and vertically cracks and vines wilt followed by a complete collapse of the plant. On dissection of infected stem, vascular tissues show brown discolouration. What to […]

Septoria Spot

(Septoria passiflorae) Credits: Biovision-Infonet The disease attacks leaves, stems and fruits. Brown spots up to 2 mm with minute, black dots (fruiting bodies containing fungal spores) develop on leaf surface. Infected leaves fall readily leading to defoliation of vines. Similar spots may form on the stems albeit elongated. On fruits light-brown spots studded with minute […]