Wilt disease
Encyclopedia
A wilt disease is any number of disease
Disease
A disease is an abnormal condition affecting the body of an organism. It is often construed to be a medical condition associated with specific symptoms and signs. It may be caused by external factors, such as infectious disease, or it may be caused by internal dysfunctions, such as autoimmune...

s that affect the vascular system of plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...

s. Attacks by fungi, bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...

, and nematode
Nematode
The nematodes or roundworms are the most diverse phylum of pseudocoelomates, and one of the most diverse of all animals. Nematode species are very difficult to distinguish; over 28,000 have been described, of which over 16,000 are parasitic. It has been estimated that the total number of nematode...

s can cause rapid killing of plants, large tree
Tree
A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...

 branches or even entire trees.

Wilt diseases in woody plants tend to fall into two major categories, those that start with the branches and those that start with the roots.
Those that start with the branches most often start with pathogens that feed on the leaves or bark, those that start with the roots start with wounding or direct entry by the pathogen into the roots, some are spread from one plant to another by way of root grafts.

Pathogen
Pathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...

s that cause wilting diseases invade the vascular vessels and cause the xylem
Xylem
Xylem is one of the two types of transport tissue in vascular plants. . The word xylem is derived from the Classical Greek word ξυλον , meaning "wood"; the best-known xylem tissue is wood, though it is found throughout the plant...

 to fail to transport water to the foliage, thus causing wilting of stems and leaves.

Bacterial wilt of cucurbits

Bacterial wilt of cucurbit
Cucurbit
Cucurbit may refer to:*A plant of the family Cucurbitaceae*The lower part of an alembic*Cucurbit flute, Chinese musical instrument...

s is cause by the bacteria Erwinia tracheiphila, it affects cucumber, squash, muskmelon, pumpkin, gourds; certain varieties of cucumber and squash have different degrees of resistance. Once a plant is infected, the bacteria spread through the xylem vessels from the area of infection to the main stem, and the entire plant wilts and dies. Initial symptoms may include the wilting of single leaves and smaller stems. Infected plants may produce a creamy white bacterial ooze when cut. The bacteria survive winter in the digestive tract of striped cucumber beetles and spotted cucumber beetles. In the spring when the beetles are feeding on susceptible plants, the bacteria, which are contained in the fecal matter of the beetles enters the plant through wounds in the epidermis
Epidermis (botany)
The epidermis is a single-layered group of cells that covers plants' leaves, flowers, roots and stems. It forms a boundary between the plant and the external environment. The epidermis serves several functions, it protects against water loss, regulates gas exchange, secretes metabolic compounds,...

. The bacteria need a film of water to facilitate infection. The bacteria can also be transmitted from one plant to another when beetles feed on an infected plant and the bacteria becomes attached to the beetles mouthparts.

The bacteria Ralstonia solanacearum
Ralstonia solanacearum
Ralstonia solanacearum is an aerobic non-sporing, Gram-negative plant pathogenic bacterium. R. solanacearum is soil-borne and motile with a polar flagellar tuft. It colonises the xylem, causing bacterial wilt in a very wide range of potential host plants...

and related species, cause bacterial wilt of banana
Banana
Banana is the common name for herbaceous plants of the genus Musa and for the fruit they produce. Bananas come in a variety of sizes and colors when ripe, including yellow, purple, and red....

s and plantain
Plantain
Plantain is the common name for herbaceous plants of the genus Musa. The fruit they produce is generally used for cooking, in contrast to the soft, sweet banana...

s. The same bacteria also cause wilt diseases of Potatoes, (Solanum tuberosum) Tomatoes, (Solanum lycopersicum) Aubergine (egg plant) (Solanum melongena), Banana, (Musa
Muša
Mūša is a river in Northern Lithuania and Southern Latvia , having its confluence with river Nemunėlis , in Latvia, near city Bauska. Mūša is a tributary of the river Lielupė. Mūša is 164 kilometres long....

species) Geranium (Pelargonium
Pelargonium
Pelargonium is a genus of flowering plants which includes about 200 species of perennials, succulents, and shrubs, commonly known as scented geraniums or storksbills. Confusingly, Geranium is the correct botanical name of a separate genus of related plants often called Cranesbills. Both Geranium...

species) Ginger, (Zingiber officinale) Tobacco, (Nicotiana tabacum
Nicotiana tabacum
Nicotiana tabacum, or cultivated tobacco, is a perennial herbaceous plant. It is found only in cultivation, where it is the most commonly grown of all plants in the Nicotiana genus, and its leaves are commercially grown in many countries to be processed into tobacco. It grows to heights between 1...

) Sweet peppers, (Capsicum
Capsicum
Capsicum is a genus of flowering plants in the nightshade family, Solanaceae. Its species are native to the Americas where they have been cultivated for thousands of years, but they are now also cultivated worldwide, used as spices, vegetables, and medicines - and have become are a key element in...

species) Olive (Olea europea) and others.

Dutch elm disease

Dutch elm disease
Dutch elm disease
Dutch elm disease is a disease caused by a member of the sac fungi category, affecting elm trees which is spread by the elm bark beetle. Although believed to be originally native to Asia, the disease has been accidentally introduced into America and Europe, where it has devastated native...

 is caused by the fungus Ophiostoma ulmi
Ophiostoma ulmi
Ophiostoma ulmi is a species of fungus in the Ophiostomataceae family. It is one of the causative agents of Dutch elm disease. It was first described under the name Graphium ulmi, and later transferred to the genus Ophiostoma....

, it affects elm
Elm
Elms are deciduous and semi-deciduous trees comprising the genus Ulmus in the plant family Ulmaceae. The dozens of species are found in temperate and tropical-montane regions of North America and Eurasia, ranging southward into Indonesia. Elms are components of many kinds of natural forests...

 trees.

Elm yellows

Elm yellows sometimes called elm phloem necrosis, affects elm trees and is caused by a Mycoplasma
Mycoplasma
Mycoplasma refers to a genus of bacteria that lack a cell wall. Without a cell wall, they are unaffected by many common antibiotics such as penicillin or other beta-lactam antibiotics that target cell wall synthesis. They can be parasitic or saprotrophic. Several species are pathogenic in humans,...

 like organism. It is spread by the white-banded leafhopper.

Oak wilt

Oak wilt is a fungal caused by Ceratocystis fagacearum, is a disease originating in eastern Russia. It can slowly or quickly kill an oak tree
Oak
An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...

 when the tree reacts to the fungus by plugging its own cambial tissue while attempting to block the spread of the fungus. This plug prevents the cambium vascular tissue from delivering nutrients and water to the rest of the plant, which eventually kills it. Red oaks are very susceptible.

Persimmon wilt

Persimmon wilt attacks persimmon
Persimmon
A persimmon is the edible fruit of a number of species of trees in the genus Diospyros in the ebony wood family . The word Diospyros means "the fire of Zeus" in ancient Greek. As a tree, it is a perennial plant...

s and is caused by Acromonium diospyri, a fungus. In the United states it has nearly eliminated persimmons from the central basin of Tennessee. Because of its lethality to persimmons, it was proposed as a biological control agent to eliminate unwanted native persimmons.

Pine wilt

Pine wilt is caused by the North American native pinewood nematode (Bursaphelenchus xylophilus
Bursaphelenchus xylophilus
Bursaphelenchus xylophilus, commonly known as pine wood nematode or pine wilt nematode , is a nematode that infects pine trees and causes pine wilt...

). Where it is indigenous
Indigenous (ecology)
In biogeography, a species is defined as native to a given region or ecosystem if its presence in that region is the result of only natural processes, with no human intervention. Every natural organism has its own natural range of distribution in which it is regarded as native...

 it is not major pathogen of native pine species, but in North America it causes wilt in a few non-native North American pine species. In has been introduced into Japan and China, where it has become a troubling disease of Japanese red pines (Pinus densiflora) and black pines (Pinus thunbergii
Pinus thunbergii
Pinus thunbergii is a pine native to coastal areas of Japan and South Korea.- Description :Japanese Black Pine can reach the height of 40 m, but rarely achieves this size outside its natural range...

). Over 46 million cubic meters of trees have been lost alone in Japan over a 50 year period. It is spread among conifers by pine sawyer beetles (Monochamus
Monochamus
Monochamus is a genus of longhorn beetles found throughout the world. They are commonly known as sawyer beetles or sawyers, as their larvae bore into dead or dying trees, especially conifers such as pines. A more ambiguous name is "bark beetles"...

spp). The nematodes can reproduce quickly in the sapwood under favorable conditions within susceptible pine species, causing wilting and death, sometimes in only a few weeks. North America lumber products are under export restrictions because of the nematode. In the Midwest United States it has killed many Scots pines (Pinus sylvestris), and this attractive tree is no longer recommended for landscaping uses there.

Stewart’s Wilt

Stewart's Wilt
Stewart's Wilt
Stewart's Wilt is a serious bacterial disease of corn caused by the bacterium Pantoea stewartii. This bacterium affects plants, particularly types of maize or corn such as sweet, flint, dent, flower and popcorn. The disease is also known as bacterial wilt or bacterial leaf blight and has shown...

 is caused by the bacteria Pantoea stewartii and affects corn plants especially sweet corn. It is a problem in the production of sweet corn in the Northeastern USA.

Verticillium wilt

Verticillium wilt
Verticillium wilt
Verticillium Wilt is a wilt disease of over 300 species of eudicot plants caused by one of two species of Verticillium fungus, V. dahliae and V. albo-atrum. Many economically important plants are susceptible including cotton, tomatoes, potatoes, eggplants, peppers and ornamentals, as well as others...

 affects over 300 species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of eudicot plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...

s caused by one of two species of Verticillium
Verticillium
Verticillium is a genus of fungi in the division Ascomycota, and are an anamorphic form of the Plectosphaerellaceae family. The genus used to include diverse groups comprising saprobes and parasites of higher plants, insects, nematodes, mollusc eggs and other fungi thus it can be seen that the...

 fungus
Fungus
A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...

, V. dahliae and V. albo-atrum. Many economically important plants are susceptible including cotton
Cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective capsule, around the seeds of cotton plants of the genus Gossypium. The fiber is almost pure cellulose. The botanical purpose of cotton fiber is to aid in seed dispersal....

, tomato
Tomato
The word "tomato" may refer to the plant or the edible, typically red, fruit which it bears. Originating in South America, the tomato was spread around the world following the Spanish colonization of the Americas, and its many varieties are now widely grown, often in greenhouses in cooler...

es, potato
Potato
The potato is a starchy, tuberous crop from the perennial Solanum tuberosum of the Solanaceae family . The word potato may refer to the plant itself as well as the edible tuber. In the region of the Andes, there are some other closely related cultivated potato species...

es, eggplants, pepper
Capsicum
Capsicum is a genus of flowering plants in the nightshade family, Solanaceae. Its species are native to the Americas where they have been cultivated for thousands of years, but they are now also cultivated worldwide, used as spices, vegetables, and medicines - and have become are a key element in...

s and ornamentals, as well as others in natural vegetation communities.
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