Powdery mildew

General Powdery mildew is a fungal disease that is caused by many different species of fungi such as Erysiphe, Podosphaera, Oïdium, Leveillula. Damage [...] underside of the leaf. On the upper side, yellow spots are noticeable. In case of a severe epidemic, the fluffy colonies also appear on the upper side of the [...] fungus causing powdery mildew is extremely sensitive to water and ‘hides’ on the underside of the leaves. Therefore, this is where the colonies mostly occur

Bacterial canker of tomato

Life cycle and appearance of Bacterial canker of tomato Clavibacter is seed-borne and tuber-borne and primary infection is mostly from infected propagation [...] only occurs in the second half of the season. The first symptoms are wilting of the lower leaves and subsequent expansion of the wilt upwards. Cutting the [...] shows whitish ooze with bacteria in the case of C lavibacter infection, but other than that the disease is difficult to distinguish from wilting caused

Phytophthora blight

sp. infestans) is also known as Phytophthora blight, tomato blight, early / late blight tomato, potato blight and late / early blight of potato. Damage [...] a period of mass starvation caused by this disease which ravaged potato crops throughout Europe during the 1840s. Life cycle and appearance of Phytophthora [...] enable them to move through water. Infection is usually from the root to the foot, but direct infection of the foot also occurs. Exudates leaking from growing

Downy mildew of Cucurbits

On the underside of the leave fluffy growth appears which is first white and later turns grey-brown. This is actually the sporulation of the pathogens extruding [...] germination free water is required. For most downy mildews, the optimum temperature is around 15 o C and the closer the temperature is to this, the shorter [...] from the stomata. Because there are more stomata on the underside of the leaf, this is where most fluffy symptoms are found. How to prevent Downey mildew

Black rot of carrots

appearance of Black rot of carrots Black rot of carrots ( Alternaria radicina ) is a seed-transferred carrot disease. The seeds are the main source of primary [...] case of black rot of carrots ( Alternaria radicina ) up to 8 years. Damage symptoms Black rot of carrots ( Alternaria radicina ) causes death of seedlings [...] primary infection and this may lead to death of seedlings. From the primary infection of leaves, this type of carrot disease can spread to the flowers (especially

Crazy roots, hairy roots, crown gall

appearance of Crazy roots, hairy roots, crown gall The primary source of infection by Rhizobium rhizogenes has not yet been defined. The assumption is that the [...] Agrobacterium rhizogenes and Agrobacterium rubi, n ow the first part of the name is changed to Rhizobium. Rhizobium rhizogenes or Rhizobium radiobacter [...] the bacteria survive in the soil, but it is possible that first infection is from the propagation material. Infection also takes place via wounds. After

Grey mould

fuckeliana / Botrytis cinerea ) is part of the foot rot complex, which causes rotting of the foot and may cause death of the plants. In cucumber and tomato [...] infection from infected parent plants. Life cycle and appearance of Grey mould Spores of grey mould ( Botryotinia fuckeliana / Botrytis cinerea ) need moisture [...] Botrytis cinerea ) is a necrotrophic fungus, meaning that it excretes compounds that kill the plant cells and then uses the content of the plant cells as

Damping-off

little of the root system survives. On the border between air and soil or substrate the plant turns brown. A typical symptom of a Pythium infection is the [...] conditions, especially dehydration. Germination of the oospores is stimulated by exudates from roots of a susceptible host nearby. The oospores germinate and form [...] in young plants and damage is more extensive in young crops. Damage symptoms Pythium affects roots, in particular those of seedlings. Infected plants lag

Black leg of seedlings

little of the root system survives. On the border between air and soil or substrate the plant turns brown. A typical symptom of a Pythium infection is the [...] the easy stripping of the skin from the root cortex with a finger nail. Life cycle and appearance of Black leg of seedlings Pythium belongs to the Oomycetes [...] conditions, especially dehydration. Germination of the oospores is stimulated by exudates from roots of a susceptible host nearby. The oospores germinate

Early blight

leathery lesions occur at the side of the stem. Life cycle and appearance of Early blight From the primary infection of leaves, Alternaria solani can spread [...] Alternaria species is the asexual stage. Conidia and mycelium overwinter in the soil and on crop residues and cause primary infection of the leaves. Survival [...] several Alternaria spp. Typically, Alternaria causes early blight of potato and early blight of tomato, which presents itself as spots on leaves, petals and