Property:Has Description

From PRG Wiki
Jump to: navigation, search

This is a property of type Text.

Pages using the property "Has Description"

Showing 25 pages using this property.

(previous 25) (next 25)


Corky Root Rot +infected roots of plants with corky root rot are distinctly corky. Extensive brown lesions, often arranged in bands with lengthwise cracking of the cortex, develop on the larger roots. The tips of infected older roots are pinched off. Small feeder roots may be completely decayed. Infected plants are stunted and slow growing. Branches on mature plants may die back from the tips.
Cucumber Mosaic Virus +Cucumber mosaic appears as a chlorosis and blistering mottle of leaves. Margins of leaves are wavy. Intense yellow flecks may develop over the leaf surface. Plants are stunted.
Curly Top Potato +Curly top symptoms include dwarfing, yellowing, and rolling of upper leaves. Leaves near the growing point develop yellow margins and become twisted and cupped. Veins of outer leaflets remain green while the rest of the leaflet turns yellow. Aerial tubers may form.
Curly Top Tomato +Plants with curly top are stunted because growth ceases. Plants turn yellow to bronze in color with purple-tinged leaves. Plants become stiff and soon die. Green fruit turns red, regardless of age.


Damping Off +Seeds may be infected as soon as moisture penetrates the seed coat or a bit later as the radicle begins to extend, all of which rot immediately under the soil surface (pre-emergence damping-off). This condition results in a poor, uneven stand of seedlings, often confused with low seed viability. Cotyledons may break the soil surface only to whither and die or healthy looking seedlings may suddenly fall over (post-emergence damping-off). Infection results in lesions at or below the soil line. The seedling will discolor or wilt suddenly, or simply collapse and die. Weak seedlings are especially susceptible to attack by one or more fungi when growing conditions are only slightly unfavorable. Damping-off is easily confused with plant injury caused by insect feeding, excessive fertilization, high levels of soluble salts, excessive heat or cold, excessive or insufficient soil moisture, or chemical toxicity in air or soil.Above ground symptoms of root rot include stunting, low vigor, or wilting on a warm day. Foliage of such plants may yellow and fall prematurely starting with the oldest leaves. The roots of a diseased plant will have some shade of brown or black and evidence of water-soaking. Healthy roots are fibrous appearing and are usually white or tan in color. These symptoms are easily confused with severe mite, aphid, scale infestations, or root-feeding by nematodes or insect larvae. Environmental factors such as accumulated salts in the soil, insufficient light or nitrogen, potbound roots, cold drafts, etc. can be eliminated only by examination of the roots.
Deforming Mosaic +Symptoms of mosaic with leaf distortion were seen in infected potato plants and a virus was suggested as the causal pathogen. In this study, we have characterised the causal agent of this disease by transmission experiments and molecular analysis of the viral genome.
Deforming Rust +Deforming rust, infection of leaves and petioles of potato
Didymella Stem Rot +Brown clear-cut lesions occur at different levels along the stem, usually at soil level and show characteristic dark dots (pycnidia).
Downy mildew +Downy mildew first appears as small, pale green to yellow, angular spots delimited by leaf veins that give the foliage a mottled appearance. Eventually the spots coalesce and the leaf will turn brown. During moist weather, the lower surface of the leaf may be covered with a white to purple growth. Older leaves become infected first.
Downy mildew lettuce +Downy mildew causes light green to yellow angular spots on the upper surfaces of leaves. White fluffy growth of the fungus develops on the lower sides of these spots. With time these lesions turn brown and dry up. Older leaves are attacked first. Severely infected leaves may die. On rare occasions the pathogen can become systemic, causing dark discoloration of stem tissue.If downy mildew infects the cotyledons of young seedlings, the plants can die. Greenhouse grown lettuce transplants can also be infected.
Downy mildew mellon +Downy mildew first appears as small, pale green to yellow, angular spots delimited by leaf veins that give the foliage a mottled appearance. Eventually the spots coalesce and the leaf will turn brown. During moist weather, the lower surface of the leaf may be covered with a white to purple growth. Older leaves become infected first.
Downy mildew sunflower +Downy mildew occurs in sunflower when 2-3 inches of rain occur within two to three weeks of planting. The only control for downy mildew has been to use Apron treated seed. Downy mildew is common in many fields, especially where heavy rains has occurred shortly after planting. Plants with systemic downy mildew are recognized by the stunted plants, yellow symptoms on the main veins and a downy white growth on the lower surface of the main veins. Occasional plants with systemic infection do not result in yield losses since nearby plants compensate in yield. When large areas of plants have systemic infection, then yield loss occurs.
Dumping-off +Seedlings affected by damping-off fail to emerge or fall over and die soon after emergence. Stems usually have a dark, shriveled portion at the soil line. Damping-off is generally limited to areas where drainage is poor or where soil is compacted, but whole fields can be affected, especially in early plantings exposed to rain.


Early Blight Tomato +"Plants infected with early blight develop small black or brown spots, usually about 0.25 to 0.5 inch in diameter, on leaves, stems, and fruit. Leaf spots are leathery and often have a concentric ring pattern. They usually appear on older leaves first. Spots on fruit are sunken, dry, and may also have a concentric pattern; frequently they occur near the calyx end of the fruit."
Early blight Potato +Early blight is primarily a disease of stressed or senescing plants. Symptoms appear first on the oldest foliage. Affected leaves develop circular to angular dark brown lesions 0.12 to 0.16 inch (3-4 mm) in diameter. Concentric rings often form in lesions to produce characteristic target-board effect. Severely infected leaves turn yellow and drop. Infected tubers show a brown, corky dry rot.
Eliciting Bacteria +Using of an elicitor to test the R-gene function instead of a pathogen. All information on gene litterature
Eliciting Fungus +Using of an elicitor to test the R-gene function instead of a pathogen. All information on gene litterature


False Root Knot Nematode +Nematodes in the genus Nacobbus produce galls that are similar in appearance to those caused by root-knot nematodes. If diagnosis is primarily based on field symptoms, it is often erroneously assumed that crop damage caused by Nacobbus species is due to Meloidogyne species. For this reason, Nacobbus species are referred to as false root-knot nematodes.
Flax rust +Rounded orange-yellow pustules develop on seedlings about mid-season. In summer, orange pustules develop on the leaves. In late summer, brown to black pustules develop on the leaves; on stems they are elongated and purplish black. Bolls break off or fail to develop.
Fusarium Crown +Foliar symptoms on plants with Fusarium crown and root rot include yellowing along the margin of the oldest leaves, followed by necrosis. Dry brown lesions develop in the cortex of the tap or main lateral roots. A necrotic lesion may also develop on the surface of the stem from the soil line to 4 to 12 inches (10?30 cm) above it. Internally, a reddish brown or chocolate-brown discoloration extends no more than 6 to 12 inches (15?30 cm) above the soil line. Infected plants may be stunted and wilted, and older plants may die.
Fusarium Dry Rots +Fusarium dry rot causes a dry rot of infected tubers, although a moist rot may occur if secondary infection by soft rot bacteria is also involved. Initially, lesions appear as brown to black flecks on the tuber surface. Lesions later form large, hollow cavities. Frequently, the lesions appear wrinkled on the tuber surface with numerous white tufts of mycelium. Infected seed pieces may completely decay.
Fusarium Foot Rot +Fusarium foot rot causes varying degrees of interveinal chlorosis and necrotic spotting on young foliage. Foliar symptoms may be similar to certain viruses (tomato spotted wilt or alfalfa mosaic). Flowers are often necrotic. Aboveground symptoms may be restricted to single branches. In severe cases, plants die. A dark brown lesion, about 0.5 to 1 inch (1?2.5 cm) long, is visible on the tap root or a main lateral root. Often the lesion completely girdles the root. The lesion usually occurs on the roots within the top 12 inches (30 cm) of soil. Internally, a brown discoloration of the vascular system extends 1 to 4 inches (2.5?10 cm) from the lesion.
Fusarium Wilt +The Fusarium wilt fungus infects plants through the rootlets, invading the xylem and eventually extending throughout the plant. Individual branches and associated leaves on plants infected with Fusarium become yellow and wilt. Sometimes only one branch or one side of the plant is affected, creating a yellow flag effect. Infected plants usually die. A dark brown vascular discoloration extends far up the stem. Symptoms often first appear during fruit sizing.


Gray Mold +Gray mold appears on young plants as gray-brown velvety mold covering stems or leaves. Infections that girdle the stem cause wilting above the infected area. In the field gray spores cover dying flowers and the calyx of fruit. Under a hand lens, the spore-bearing structures resemble bunches of grapes. Infections spread from flowers or fruit back toward the stem, which turns white and develops a canker that may girdle it.


Kinase +Kinase domain involved in resistance process
(previous 25) (next 25)
Personal tools