Root rot of carrot

General Black spots on cold-stored carrots are a major problem and can lead to significant postharvest losses Several different fungal pathogens cause [...] diseases. When carrots are stored during winter, diseases on the carrot roots can continue to develop during storage. Alternaria radicina , Alternaria dauci [...] Damage symptoms Rhexocercosporidium carotae is a slow-growing fungus that can infect both roots and foliage. The infection starts with small black spots

Fusarium spp.

species. Fusarium is widespread and can infect a range of host crops. Many species are considered weak pathogens and can only infect wounded or stressed host [...] species. Fusarium is widespread and can infect a range of host crops. Many species are considered weak pathogens, which can only infect wounded or stressed [...] host plants. Three pathogens can be distinguished: Fusarium oxysporum ( Fusarium wilt ): Many different hosts, potato ( Solanum tuberosum ), most vegetables

Bacterial canker of tomato

potatoes or other Solaneceaous crops can be planted for five years. On other fields on the same farm, no seed potatoes can be grown for one year after infection [...] blocked. The bacterium can survive some time in crop residues like volunteer tubers and potato crop residues. Infected tubers can infect healthy tubers [...] the plants in the infected area, with a substantial buffer zone. Replanting can only take place after thorough disinfection has been proven to the authorities

Black root rot of cucurbits

survives in the soil and is a strong saprophytic competitor, which means it can rapidly colonize ‘clean’ or sterilized soil and substrate. It aggregates, [...] applied thoroughly and evenly. Phomopsis sclerotioides forms sclerotia which can survive adverse conditions for years in the soil, but little else is known [...] approximately 20 °C whereas at 10 °C the lesions are light-brown. The lesions can be enclosed by pseudostromata: dark coloured tissue that looks like black

Southern blight

susceptible, but it can invade via direct penetration, generally close to the surface of the stem. In favourable conditions, the sclerotia can germinate in two [...] texture and humidity close to field capacity. In the southern USA, losses can reach 5% of annual production. Symptoms and damage Symptoms begin with brown [...] sclerotia. They are round and their diameter varies from 0.4 to 2 mm. They can be dispersed via water, agricultural tools, and contaminated seeds. The favourable

Early blight

and on crop residues and cause primary infection of the leaves. Survival can be several years, up to eight years for several Alternaria spp. Typically [...] which presents itself as spots on leaves, petals and stems. These spots can be distinguished by the dark and brown concentric rings that are caused by [...] brown angular lesions with a yellow halo restricted by leaf veins. Lesions can easily rupture. Other symptoms are brown lesions on stem and foot. On fruits

Fusarium wilt

species. Fusarium is widespread and can infect a range of host crops. Many species are considered weak pathogens and can only infect wounded or stressed host [...] wilts. Other symptoms are brown discolouration of the xylem vessels which can be seen when the stems are cut. In banana, whole plantations may die and the [...] residues Choose resistant cultivars Use clean propagation materials (seed can be treated effectively with hot water) Use clean substrate in greenhouse crops

Grape downy mildew

ing regions worldwide. Damage symptoms of Grape downy mildew P. viticola can infect all green parts of the host plant with stomata, giving following symptoms: [...] conditions they are covered with cottony spores. Early infected clusters can turn brown, dry, and fall off; later infections cause discoloration and shriveling [...] overwinters as oospores in fallen, infected leaves. In mild climates, it can also survive as mycelium in grape buds and canes. In spring, oospores germinate

Verticillium wilt

senescence, without any other typical symptoms. In many crops, the fungus can be present without clear symptoms or with only partial wilting. Life cycle [...] years) in the soil as microsclerotia, small hard survival structures that can withstand high and low temperatures and dehydration. Verticillium dahliae [...] to plant takes place via water, soil particles, tools, etc. Verticillium can also be seed-borne and tuber-borne. The optimum temperature for Verticillium

Bacterial soft rot, bacterial stem rot

is very common, but does not often reach epidemic population densities. It can survive as epiphytic bacteria on various plants or in the soil in low densities [...] wounds, for example pruning wounds. It cannot infect healthy green leaves, but can grow in senescent leaves and from there grow through the petiole to the main [...] development. Erwinia carotovora subsp. carotovora or Pectobacterium carovora can also be found as secondary pathogen in plants that are infected by other pathogens