• Wheat bunt

  General Tilletia tritici and Tilletia laevis only differ in one gene and easily hybridize. There is debate whether they should indeed be considered separate species, since they cause the exact same symptoms. Tilletia tritici and Tilletia laevis cause diseases such as common wheat bunt, stinking smut, karnal bunt of wheat. Damage symptoms Plantsinfected by Tilletia tritici and Tilletia laevis are hard to distinguish from infected plants before head

• Bacterial spot

  General Xanthomonas vesicatoria is a bacterium that causes bacterial leaf spot on peppers and tomatoes. Damage symptoms Xanthomonas vesicatoria in tomato causes small, water-soaked spots on leaves which are first round and become more angular as they grow. The centre of the lesions may fall out as they become drier. Under humid conditions, the spots may merge with lesions on the petioles and stems and form long dark streaks. On fruits, first small

• Leaf stripe

  General Pyrenophora graminea is a disease of Barley that causes significant yield losses. Damage symptoms Symptoms first occur on the first, second and third leaf and subsequently on other leaves. Yellow stripes are formed at the base of the leaf and the leaf sheath. They gradually extend and become brown and chlorotic and may merge. Eventually this leads to the death of the leaf. The leaf splits at the end which makes it look shredded. This is

• Bacterial soft rot, bacterial stem rot

  General Erwinia carotovora subsp. carotovora has recently been renamed Pectobacterium carotovora . It is one of the pectolytic bacteria causing extensive bacterial rots (bacterial soft rot, bacterial stem rot). Damage symptoms In tomato, Erwinia carotovora subsp. carotovora or Pectobacterium carovora causes bacterial stem rot as well as soft rot. Stem rot is first noticed when plants wilt at the time of first harvest or after that. The pith disintegrates

• Angular leaf spot

  General Xanthomonas fragariae is a leaf spot disease found in strawberry. Damage symptoms Xanthomonas fragariae initially causes small, water-soaked lesions 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 using different light sources: when reflected light is used, the lesions look dark green, but when transmitted light is used, they are

• Gummy stem blight

  General Mycosphaerella cucumis (Didymella bryoniae) is a fungal plant pathogen that causes gummy stem blight. Damage symptoms Mycosphaerella cucumis in cucumber causes brown lesions on the foot and higher up on the stem. On the lesions, golden-brown gummy drops occur, hence the name gummy stem blight. On the lesions, black specks, the new fruiting bodies with spores, become visible. On the leaves, round and extending lesions may occur. In cucumber

• Black root rot of cucurbits

  General Phomopsis sclerotioides is a plant pathogen infecting cucurbits, causing black root rot of cucurbits. Damage symptoms Phomopsis sclerotioides causes grey-black spots with a dark demarcation line on cucumber roots. The lesions are slightly sunken and are mostly formed around the point of attachment of lateral roots and root hairs. The lesions may grow and encircle the root. The roots become yellow-brown to black and ultimately die. Black

• Root and crown rot of strawberry

  General New diseases in strawberry have been ascribed to Pestalotiopsis clavispora in the case of root and crown rot (of strawberry), first found in The Netherlands, and Pestalotiopsis longisetula in the case of leaf spots, such as leaf spot of strawberry and fruit rot reported mainly from Brazil. The genus is quite complex, so the taxonomy may change. Pestalotiopsis clavispora is also called Neopestalotiopsis clavispora. Pestalotiopsis clavispora

• Pea blight, leaf and pod spot

  General Ascochyta pisi is a fungal plant pathogen that causes A scochyta blight on pea (leaf blight or pea blight) and lesions of stems, leaves, and pods (pea leaf spot and pea pod spot). Damage symptoms Ascochyta pisi causes spots on leaves, stems and pods of peas. The spots on leaves and pods are round, on the stems they are more elongated. The lesions are light brown, sunken and surrounded by a dark brown to red-brown border. The first infection

• Bacterial wilt, brown rot

  General Ralstonia solanacearum is a plant pathogenic bacterium. It is a soil-borne disease and colonises the xylem, causing bacterial wilt and brown rot in a very wide range of potential host plants. Damage symptoms In potato, field symptoms of Ralstonia solanacearum are wilting and yellowing of leaves and stunted plants. Inside, vascular browning is common with bacterial slime oozing from the cut. When the bacteria transfers to young plants