• Loose smut of barley

  Ustilago nuda f.sp. hordei affects barley and can destroy a large proportion of the crop. It is also known as barley smut, or loose smut of barley. Damage [...] symptoms Infection by Ustilago nuda f. sp. hordei r emains invisible until head emergence. The first sign of infection is the appearance of a smutted ear. Instead [...] Instead of normal tissue, the ear contains a mass of olive-brown smut spores. Life cycle and appearance of Loose smut of barley The seeds are infected

• Fusarium head blight or scab

  General Fusarium is a group of soil-borne fungi with many different species. Fusarium is widespread and can infect a range of host crops. Many species [...] species are considered weak pathogens and can only infect wounded or stressed host plants. Damage symptoms Fusarium fungi cause vascular wilt, root rot, foot [...] head blight in cereals, such as wheat (fusarium head blight wheat) and post-harvest decay. Life cycle and appearance of Fusarium head blight or scab Most

• Pierce's disease of grapevine

  Xylella fastidiosa is a gram-negative bacterium which is limited to xylem tissue. It has many hosts, many of which show minor or no symptoms. More and [...] discovered as hosts. Xylella fastidiosa is best known in grapevine, stone fruit (peach and plum) and citrus, where it causes diseases such as Pierce's disease [...] disease of grapevines, phony peach disease, plum leaf scald, citrus variegated chlorosis and quick decline syndrome. Recently, it is becoming more problematic

• Wheat bunt

  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 [...] such as common wheat bunt, stinking smut, karnal bunt of wheat. Damage symptoms Plantsinfected by Tilletia tritici and Tilletia laevis are hard to distinguish [...] may be slightly stunted. Infected (bunted) heads are slender and remain green longer than healthy heads. The glumes are opened either on some or on all

• Bacterial spot

  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 [...] spots may merge with lesions on the petioles and stems and form long dark streaks. On fruits, first small black specks are seen on green fruits. The specks

• 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 [...] 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 [...] leads to the death of the leaf. The leaf splits at the end which makes it look shredded. This is typical for this disease. Infected plants may be stunted

• Bacterial soft rot, bacterial stem rot

  carotovora . It is one of the pectolytic bacteria causing extensive bacterial rots (bacterial soft rot, bacterial stem rot). Damage symptoms In tomato, Erwinia [...] 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 [...] harvest or after that. The pith disintegrates and the stem becomes hollow. Because of the bacterial growth in the pith, the stem seems wet and slimy. Above

• Angular leaf spot

  fragariae is a leaf spot disease found in strawberry. Damage symptoms Xanthomonas fragariae initially causes small, water-soaked lesions on the underside [...] 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 [...] reflected light is used, the lesions look dark green, but when transmitted light is used, they are translucent. When conditions are humid, a viscous bacterial

• Gummy stem blight

  bryoniae) is a fungal plant pathogen that causes gummy stem blight. Damage symptoms Mycosphaerella cucumis in cucumber causes brown lesions on the foot [...] 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 [...] visible. On the leaves, round and extending lesions may occur. In cucumber, the most important symptom is internal fruit rot, which can only be recognized

• 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 [...] 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 [...] yellow-brown to black and ultimately die. Black lesions with fruiting bodies occur more commonly at temperatures of approximately 20 °C whereas at 10 °C the lesions