Wheat seed and leaf gall nematode | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Nematoda |
Class: | Secernentea |
Order: | Tylenchida |
Family: | Heteroderidae |
Genus: | Anguina |
Species: | A. tritici |
Binomial name | |
Anguina tritici (Steinbuch, 1799) Chitwood, 1935 | |
Synonyms [1] | |
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Anguina tritici (ear-cockle nematode, seed-gall nematode, seed and leaf gall nematode, wheat gall nematode, wheat seed gall nematode, wheat seed-gall nematode, wheat seed and leaf gall nematode) is a plant pathogenic nematode. [2] [3] [4]
Anguina tritici was the first plant parasitic nematode to be described in the literature in 1743. It causes a disease in wheat and rye called "ear-cockle" or seed gall. Originally found in many parts of the world but has been eradicated from the western hemisphere. Currently in north Africa and west Asia only. [5] Yield losses up to 70% have been reported, ranging from 30-70%. [6] Threshold of 10,000 juveniles/kg soil develop disease.[ citation needed ]
It is a large nematode, ranging from 3–5 millimetres (1⁄8–1⁄4 in) in length. Anguina tritici has a three part esophagus and the esophageal glands do not overlap with intestine. The female body tends to be thickened and curved ventrally. It has a short stylet (8-11 μm). Females have one ovary and the vulva located posterior. Males possess small spicules and small bursae or alae.
Juveniles find a host and move up the plant in a film of water. They invade meristems and penetrate inflorescences. Once in the developing seed they molt, become adults, mate, and reproduce. Eggs laid by the female develop and hatch as J2 within the seed gall where they desiccate and become dormant. Dormant J2 overwinter in the seed galls until spring. They are released when galls come in contact with moist soil and hydrate. Total life cycle is completed in 113 days.
It is an ectoparasite that becomes endoparasitic invading inflorescence and developing seeds. It causes a disease called "ear-cockle", "gout" or seed gall on wheat and rye, and also infects barley and oat. [7] : 784 It does not infest maize or sorghum. On wheat it causes stunted plants and distorted leaves. Seeds are transformed into galls which contain a dried mass of nematodes. If compared to normal wheat seeds, galls are smaller in size, lighter, and their color ranges from light brown to black (normal wheat seeds are tan in color). [8]
The disease has been eradicated by seed sanitation methods. Seed certification programs get rid of galls (lighter and less dense than seed) by flotation, hot water treatments, winnowing or gravity table seed processing.
Root-knot nematodes are plant-parasitic nematodes from the genus Meloidogyne. They exist in soil in areas with hot climates or short winters. About 2000 plants worldwide are susceptible to infection by root-knot nematodes and they cause approximately 5% of global crop loss. Root-knot nematode larvae infect plant roots, causing the development of root-knot galls that drain the plant's photosynthate and nutrients. Infection of young plants may be lethal, while infection of mature plants causes decreased yield.
Meloidogyne incognita, also known as the southern root-nematode or cotton root-knot nematode is a plant-parasitic roundworm in the family Heteroderidae. This nematode is one of the four most common species worldwide and has numerous hosts. It typically incites large, usually irregular galls on roots as a result of parasitism.
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Rotylenchulus reniformis, the reniform nematode, is a species of parasitic nematode of plants with a worldwide distribution in the tropical and subtropical regions.
Aphelenchoides ritzemabosi is a plant pathogenic nematode. It was first scientifically described in 1890 in England. This nematode has a wide host range. Among the most important species affected are Chrysanthemums and strawberries. A. ritzemabosi is a migratory foliar feeding nematode. It can feed both ectoparasitically and endoparasitically, with the later causing the most significant damage. When adequate moisture is present, this nematode enters the leaves and feeds from inside the tissue. Typical damage is characterized by necrotic zones between the veins of the leaves. Its lifecycle is short; only ten days from egg to mature adult. A single female can lay as many as 3,500 eggs. This pest can be difficult to control. Host plant resistance, hot water treatments, and predatory mites are recommended.
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Meloidogyne brevicauda is a plant-parasitic nematode. It is also called tea root-knot nematode, mature tea nematode or Indian root-knot nematode. It is a member of the root-knot nematodes, which was identified by C. A. Loos in 1953 in Sri Lanka.
Mesocriconema xenoplax is a species of plant parasitic nematodes. Nematodes of this particular species are collectively called ring nematodes.
There are many plant-parasitic species in the root-knot nematode genus (Meloidogyne) that attack coffee such as M. incognita, M. arenaria, M. exigua, M. javanica and M. coffeicola. Study has already shown interspecific variability coffee, in which show how this species can be adapting to new hosts and environments.
Anguina agrostis is a plant pathogenic nematode.
Heterodera sacchari, the sugarcane cyst nematode, mitotic parthenogenic sedentary endoparasitic nematode. This plant-parasitic nematode infects the roots of sugarcane, and the female nematode eventually becomes a thick-walled cyst filled with eggs. Aboveground symptoms are species specific and are similar to those caused by other Heterodera species. Symptoms include: stunted and chlorotic plants, and reduced root growth. Seedlings may be killed in heavily infested soils.
Anguina is a genus of plant pathogenic nematodes.
Anguina amsinckiae is a plant pathogenic nematode, which attacks the weed called fiddleneck.
Nematology is the scientific discipline concerned with the study of nematodes, or roundworms. Although nematological investigation dates back to the days of Aristotle or even earlier, nematology as an independent discipline has its recognizable beginnings in the mid to late 19th century.
Pratylenchus is a genus of nematodes known commonly as lesion nematodes. They are parasitic on plants and are responsible for root lesion disease on many taxa of host plants in temperate regions around the world. Lesion nematodes are migratory endoparasites that feed and reproduce in the root and move around, unlike the cyst or root-knot nematodes, which may stay in one place. They usually only feed on the cortex of the root. Species are distinguished primarily by the morphology of the stylets.
Heterodera zeae, the corn cyst nematode (CCN), is a plant parasitic nematode that feeds on Zea mays (maize/corn). The CCN has a limited economic impact worldwide due to its high soil temperature requirements.
Lolium rigidum is a species of annual grass. Common names by which it is known include annual ryegrass, a name also given to Italian ryegrass, rigid ryegrass, stiff darnel, Swiss ryegrass and Wimmera ryegrass. It is a native of southern Europe, northern Africa, the Middle East and the Indian subcontinent and is grown as a forage crop, particularly in Australia, where it is also a serious and economically damaging crop weed.