• Apple scab

  become grey and fluffy. The lesions caused by ascospores are more restricted, whereas the lesions caused by conidia extend faster and may merge. Infected [...] harmed by for example application of compounds against stem canker, since they help in decomposing the infected leaves Prevent plant diseases by optimizing [...] produce corky rings around the lesions to prevent further invasion of tissue by the fungus. Late fruit infection only results in small dark lesions which

• Phytophthora blight

  protrude through the stomata. Secondary infection is either by germinating sporangia or by zoospores produced in the sporangia. For germination on above-ground [...] fast drying and wound healing, by allowing air circulation Disinfect recirculating nutrient solutions Prevent plant diseases by optimizing plant potential [...] through the skin. The Great Famine was a period of mass starvation caused by this disease which ravaged potato crops throughout Europe during the 1840s

• Gummy stem blight

  wounds and by the infected leaves through the petioles. Fruits are infected through the flowers. The newly produced ascospores are dispersed by air and the [...] symptom is internal fruit rot, which can only be recognized from the outside by the small narrowing of the tip of the mature fruits. The symptoms on stems [...] the conidiospores by water drops, tools and hands of workers. The ascospores are the main source of dispersal of disease upwards in the crop and the conidia

• Early blight

  petals and stems. These spots can be distinguished by the dark and brown concentric rings that are caused by sporulation. Species may differ in specific symptoms [...] spots then turn into dark brown angular lesions with a yellow halo restricted by leaf veins. Lesions can easily rupture. Other symptoms are brown lesions on [...] Infection is both direct and through wounds and stomata. Spores are dispersed by wind and in some species through the splash of rain. How to prevent Early

• Bacterial canker of tomato

  propagation material. It spreads to other seedlings by touching the plants in greenhouse crops and by water in field crops, for example through splashes [...] bacteria. The bacteria can also be dispersed by machinery, crates and tools. The bacteria infect the new plants by entering through wounds and then growing [...] other than that the disease is difficult to distinguish from wilting caused by other pathogens. On potato tubers, first discolouration of the vessel tissue

• Root and crown rot of strawberry

  been weakened by some form of stress, from underfertilization to water stress (either too much or too little water), or that are damaged by for example handling [...] disease development Provide balanced nutrition Avoid damage to the plants by pest insects or plant handling Take hygienic measures: Remove any infected [...] subsequent crops Disinfect water used for irrigation Prevent plant diseases by optimizing plant potential and crop resilience.

• Downy mildew of Cucurbits

  also stems and fruits. They cause lesions on the upper leaf surface, bordered by the veins, which are first yellow and then turn brown. On the underside of [...] and the germ tubes infect the plants either through the stomata or directly by penetrating the cuticula. For germination free water is required. For most [...] crop rotation with non-host crops Prevent a humid microclimate. Achieve this by lowering crop density, good aeration during propagation and maintaining a

• Glume blotch

  secondary infection by splash dispersal. Splashing rain water helps the fungus to reach the upper leaves and ears. Seed infection is enhanced by wet weather [...] Conidia require a minimum of 5 °C for germination. Primary infection is mostly by ascospores or conidia on the oldest leaves, but seed transmission is also [...] is more efficient so the disease will spread faster Prevent plant diseases by optimizing plant potential and crop resilience.

• Damping-off

  that are in a sub-optimal condition or suffer from stress, caused for example by too much water, too high or low temperatures or sudden fluctuations in temperature [...] conditions, especially dehydration. Germination of the oospores is stimulated by exudates from roots of a susceptible host nearby. The oospores germinate and [...] or substrate. Oospores are dispersed when soil particles are moved around by humans or machinery. Pythium can survive very well in the soil or substrate

• Angular leaf spot

  on the underside of the leaf. They enlarge to angular spots, often limited by the small veins. The distinctive feature is the way the lesions look when [...] on the leaves and form a secondary source of infection. They are dispersed by rain, irrigation water or handling of the plants. Infection of the plants [...] both passively and actively. Infection and disease development are favoured by temperatures around 20 °C during the day and cold nights, in combination with