• Verticillium wilt

  vessels. The presence of both the fungus and the gum causes the xylem vessels to get blocked, which in turn causes the plant to wilt. Spores may be wind-dispersed [...] wind-dispersed to new hosts. In the senescent tissue, the resting mycelium or the microsclerotia are formed. The spread of the fungus by mycelium growth is limited [...] cause wilting of plants. The wilting starts at the lower leaves. These leaves are pale-green, then orange-yellow. In the beginning the plant seems to recover

• Pierce's disease of grapevine

  along the margin or the tip from early to midsummer. The necrotic area spreads over the leaf from the margin and is marked by a chlorotic band. In the beginning [...] substance, in the vessels. The bacteria, gum and tyloses block the vessels, causing the plants to wilt. Transport to different plant parts depends on the plant [...] plums): In peach, the canopy of infected plants is compact and umbrella-like due to the shorter internodes. The foliage is denser and the leaves are a darker

• Bacterial canker of tomato

  brown centre. In potato, the disease usually only occurs in the second half of the season. The first symptoms are wilting of the lower leaves and subsequent [...] expansion of the wilt upwards. Cutting the stem at the foot shows whitish ooze with bacteria in the case of C lavibacter infection, but other than that the disease [...] then growing into the vessels of the plant. Plant growth is inhibited and the plant wilts because the xylem vessels become blocked. The bacterium can survive

• Dwarf bunt

  sporidia infect the wheat seedlings even before emergence and the fungi grow inside the plants to the growing tip. The fungi grow between the plant cells and [...] survives as teliospores in the soil or on seed. The soil-borne teliospores are the main source of primary infection. The soil-borne teliospores may survive [...] heads. The glumes are opened either on some or on all spikelets, showing the bunt (smut spore) they contain, which is larger than a normal kernel. The bunt

• Downy mildew of Cucurbits

  For most downy mildews, the optimum temperature is around 15 o C and the closer the temperature is to this, the shorter the leaf wetness period that is [...] Inside the plant, the pathogens produce haustoria, small organs with which the pathogen can take up nutrients from the living plant cells. The pathogens [...] brown. On the underside of the leave fluffy growth appears which is first white and later turns grey-brown. This is actually the sporulation of the pathogens

• Damping-off

  bulbs. At first, the plants recover during the night, but later the plants wilt irreversibly. In potted plants the flower buds fall off. The side roots rot [...] of the root system survives. On the border between air and soil or substrate the plant turns brown. A typical symptom of a Pythium infection is the easy [...] enable the spores to move through water. The zoospores are chemically drawn to the growing roots of young plants and move towards them through the soil water

• Loose smut of barley

  survives inside the seed and when the seed germinates, the mycelium of the fungus grows upwards inside the plant into the growing tip and the seed primordia. It [...] smut of barley The seeds are infected during flowering and the infected seeds are the primary source of inoculum in the next crop. The fungus survives [...] invisible until head emergence. The first sign of infection is the appearance of a smutted ear. Instead of normal tissue, the ear contains a mass of olive-brown

• Loose smut of wheat

  survives inside the seed and when the seed germinates, the mycelium of the fungus grows upwards inside the plant into the growing tip and the seed primordia. It [...] Loose smut of wheat The seeds are infected during flowering and the infected seeds are the primary source of inoculum in the next crop. The fungus survives [...] invisible until head emergence. The first sign of infection is the appearance of a smutted ear. Instead of normal tissue, the ear contains a mass of olive-brown

• Crazy roots, hairy roots, crown gall

  crown gall The primary source of infection by Rhizobium rhizogenes has not yet been defined. The assumption is that the bacteria survive in the soil, but [...] caused by a change in the hormonal system of the plant resulting from the Rhizobium infection. Rhizobium rhizogenes puts a Ri-plasmid in the plant tissue and [...] Adjust the work order in greenhouses to fit with the hygiene protocol Disinfect the nutrient solution in order to prevent biofilm growth inside the irrigation

• Wheat bunt

  sporidia infect the wheat seedlings even before emergence and the fungi grow inside the plants to the growing tip. The fungi grow between the plant cells and [...] heads. The glumes are opened either on some or on all spikelets, showing the bunt (smut spore) they contain, which is larger than a normal kernel. The bunt [...] sporidium. Two mating types are distinguished. The filiform basidiospores fuse in the middle with a basidiospore of the other mating type so that H-shaped structures