Powdery mildew

walls and makes it harder for the fungi to enter the leaves To reduce chances of powdery mildew in greenhouses, it is advised to first ventilate by only [...] Ascospores have not been found yet for all powdery mildew fungi and especially in greenhouse crops they don’t play a role in the epidemics. Fungal spores germinate [...] explode when in contact with water for no more than a few hours. Powdery mildew spores, either ascospores or conidia, don’t need nutrients or water for germination

Gummy stem blight

the main source of dispersal of disease upwards in the crop and the conidia for spread of the disease downwards. How to prevent Gummy stem blight Before [...] makes it harder for the fungi to enter the leaves Pick flowers within two days after opening in areas suspected of disease (only feasible in high-wire crops) [...] cucumis (Didymella bryoniae) is a fungal plant pathogen that causes gummy stem blight. Damage symptoms Mycosphaerella cucumis in cucumber causes brown lesions

Black leg of seedlings

that allow the disease to spread to neighbouring plants. The zoospores disperse via water. Therefore, this disease spreads most rapidly in wet conditions [...] considered a ‘weak pathogen’, meaning that it can usually only affect plants that are in a sub-optimal condition or suffer from stress, caused for example [...] survive very well in the soil or substrate in the absence of plants. Many species are entirely saprophytic, so these do not harm plants. How to prevent Black

Angular leaf spot

overwinters in plants and dead leaves, that become the primary source of infection in the spring. The bacteria are also introduced in a crop in new transplants [...] bacterium is very resistant to desiccation and can survive well in dry leaves or leaves in the soil, but not independantly in the soil. Under humid conditions [...] plants. How to prevent Angular leaf spot Use clean propagation material and disease-free seed Remove sources of inoculum such as dead leaves In field-grown

Brown root rot, corky root rot

cultivation practices. However, this fungus is a poor competitor against a balanced microbial population in soil. How to prevent Brown root rot, corky root rot [...] lycopersici survives in the soil and in buried tomato roots as microsclerotia. The microsclerotia germinate and produce mycelium that in turn infect the roots [...] symptoms The first signs of this disease, are poorly looking plants in localized areas of the greenhouse or field. The affected plants may wilt. Also, interveinal

Dwarf bunt

which in turn become a source of disease in the next season. The optimum temperature for germination is 3-8 °C and it takes three to ten weeks for germination [...] General Tilletia controversa is a plant pathogen. It is a fungus known to cause the smut disease TCK smut in soft white and hard red winter wheats, as [...] the whole kernel becomes a bunt ball full of teliospores. These balls break during harvest allowing the teliospores to fall to the ground. Additionally

Damping-off

that allow the disease to spread to neighbouring plants. The zoospores disperse via water. Therefore, this disease spreads most rapidly in wet conditions [...] considered a ‘weak pathogen’, meaning that it can usually only affect plants that are in a sub-optimal condition or suffer from stress, caused for example [...] survive very well in the soil or substrate in the absence of plants. Many species are entirely saprophytic, so these do not harm plants. How to prevent Damping-off

Charcoal rot

regions it is therefore not a problem. How to prevent Charcoal rot Plant in fields with no history of the disease Use disease-free planting material Rotate [...] considered a main source of infection. Optimum conditions for this fungus are temperatures above 32 °C and dry conditions. In field crops in temperate regions [...] General Macrophomina phaseolina is a common soil fungus in warmer regions, causing charcoal rot. It has a very wide range of host crops, many of which

Bacterial spot

isolates are resistant to copper-containing pesticides. How to prevent Bacterial spot Use clean propagation material and disease-free seed Remove sources [...] like scab. These spots may be surrounded by a halo. In pepper, the spots on the leaves are also round and small to start with and slightly raised from the [...] survives on volunteer tomato plants in the field and on diseased plant debris. The bacteria are also seed-transmitted. Disease development is favoured by te

Wheat bunt

kernels, which in turn become a source of disease in the next season. Infection is strongly correlated to temperature and precipitation in the first 11 days [...] and Tilletia laevis survive as teliospores in the soil or on seed. These teliospores germinate in response to moisture and form basidiospores, also called [...] the whole kernel becomes a bunt ball full of teliospores. These balls break during harvest allowing the teliospores to fall to the ground. Additionaly,