Helicotylenchus multicinctus | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Nematoda |
Class: | Secernentea |
Order: | Tylenchida |
Family: | Hoplolaimidae |
Genus: | Helicotylenchus |
Species: | H. multicinctus |
Binomial name | |
Helicotylenchus multicinctus (Cobb, 1893) Golden, 1956 | |
Synonyms | |
Tylenchus multicinctus Contents |
Helicotylenchus multicinctus is a plant pathogenic nematode that affects primarily bananas and plantains. Nematodes of the genus Helicotylenchus are spiral nematodes and feed on a large variety of plant species.
Helicotylenchus multicinctus was first described by Nathan A. Cobb in 1893 as Tylenchus multicinctus. After further study by A.M. Golden in 1956 it was transferred to the genus Helicotylenchus . [1] As a plant parasitic nematode of bananas it is often considered second in importance to Radopholus similis . [2]
Found in most banana and plantain growing regions of the world including tropical and temperate regions of Asia, Africa, North America, Central America, South America and the Pacific Islands. [2]
Refer to Helicotylenchus for morphological description
The average life cycle is 30–45 days. The first stage juvenile and first molt are completed within the egg. Second stage juveniles possess a digitate tail. The esophagus measures 41% of the body length with a 14 μm stylet. After the second molt the tail disappears and there is rapid growth in the intestine region. Female gonad development begins in the third stage juvenile with the esophagus measuring 28% body length and the stylet measuring 18 μm. After the fourth molt female gonads are completely developed but the vulva and vagina are not visible until molting is complete. An adult female has an esophagus measuring 22% body length and a stylet of 22.5 μm. Males are shorter and thinner than females. [3]
Helicotylenchus multicinctus feeds primarily on cortical root tissue 4–6 cells deep. [3] The nematode produces small lesions that are mostly shallow and superficial. Heavy infestations may cause root necrosis. Ultimately feeding deprives the plant of water and nutrients and can lead to shorten plant stand. [2]
Nematodes are spread through the soil and through infested banana plantlets. The best option is to ensure that banana corms are free of any nematodes prior to planting. Researchers in Hawaii found that a hot-water treatment at 50 °C for 10 minutes was enough to kill all nematodes in a corm 2–6 inches thick. Soil solarization, or heating and insulating of the soil, can cause nematode death although heat may not penetrate deep enough to kill all nematodes. Cover crops such as sunn hemp and some species of marigold may reduce the amount of spiral nematodes in the soil prior to banana establishment. [4] Nematicides are also an option. In Africa, nematicides applied with drip irrigation have showed to decrease cost and increase effectiveness. [5]
Radopholus similis is a species of nematode known commonly as the burrowing nematode. It is a parasite of plants, and it is a pest of many agricultural crops. It is an especially important pest of bananas, and it can be found on coconut, avocado, coffee, sugarcane, other grasses, and ornamentals. It is a migratory endoparasite of roots, causing lesions that form cankers. Infected plants experience malnutrition.
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.
Rotylenchulus reniformis, the reniform nematode, is a species of parasitic nematode of plants with a worldwide distribution in the tropical and subtropical regions.
Meloidogyne arenaria is a species of plant pathogenic nematodes. This nematode is also known as the peanut root knot nematode. The word "Meloidogyne" is derived from two Greek words that mean "apple-shaped" and "female". The peanut root knot nematode, M. arenaria is one of the "major" Meloidogyne species because of its worldwide economic importance. M. arenaria is a predominant nematode species in the United States attacking peanut in Alabama, Florida, Georgia, and Texas. The most damaging nematode species for peanut in the USA is M. arenaria race 1 and losses can exceed 50% in severely infested fields. Among the several Meloidogyne species that have been characterized, M. arenaria is the most variable both morphologically and cytologically. In 1949, two races of this nematode had been identified, race 1 which reproduces on peanut and race 2 which cannot do so. However, in a recent study, three races were described. López-Pérez et al (2011) had also studied populations of M. arenaria race 2, which reproduces on tomato plants carrying the Mi gene and race 3, which reproduces on both resistant pepper and tomato.
Meloidogyne javanica is a species of plant-pathogenic nematodes. It is one of the tropical root-knot nematodes and a major agricultural pest in many countries. It has many hosts. Meloidogyne javanica reproduces by obligatory mitotic parthenogenesis (apomixis).
Pratylenchus zeae is a plant-pathogenic nematode found on potatoes, maize, cereal, tobacco, coffee, blackberry, and found most often on sugarcane.
Ditylenchus destructor is a plant pathogenic nematode commonly known as the potato rot nematode. Other common names include the iris nematode, the potato tuber eelworm and the potato tuber nematode. It is an endoparasitic, migratory nematode commonly found in areas such as the United States, Europe, central Asia and Southern Africa.
Anguina tritici is a plant pathogenic nematode.
Hirschmanniella oryzae, i.e. rice root nematode (RRN), is among the major pests of rice and is the most common plant-parasitic nematode found on irrigated rice. Recent modifications in cultivation practices have led to a substantial increase in rice production, which has been accompanied by heightened levels of RRN. The proportional increases in RRN with rice production can be explained by the nematode's impeccable adaptation towards constantly flooded conditions in which irrigated rice is often being grown.
Paratylenchus hamatus, the fig pin nematode, is a species of migratory plant endoparasites, that causes lesions on plant roots resulting in symptoms of chlorosis, wilting and ultimately yield losses. They move and feed on different parts of host tissue throughout their life cycle in order to find enough susceptible host tissue to survive and reproduce. A wide range of host plant species are susceptible to the fig pin nematode, including many valuable fruit and vegetable crops such as figs, carrots and celery. They are also commonly found associated with woody perennials in California. P. hamatus inhabits soils in both Europe and North America, and was originally isolated from fig in central California in 1950.
Xiphinema americanum, the American dagger nematode, is a species of plant pathogenic nematodes. It is one of many species that belongs to the genus Xiphinema. It was first described by N. A. Cobb in 1913, who found it on both sides of the United States on the roots of grass, corn, and citrus trees. Not only is Xiphinema americanum known to vector plant viruses, but also X. americanum has been referred to as "the most destructive plant parasitic nematode in America", and one of the four major nematode pests in the Southeastern United States.
Xiphinema diversicaudatum is an amphimictic ectoparasitic nematode species. This species has a characteristically long stylet capable of penetrating into a host's vascular tissue. They have a wide host range with some of the extensively studied ones being strawberry, hops and raspberry, due to their economic importance. The direct root damage caused through penetration near the root tip and formation of galls is a secondary concern when compared with the damage caused by vectoring the Arabis mosaic virus. The virus attaches to the interior cuticle lining and can be transferred from infected to uninfected root tissue as the nematode feeds and sheds. Management of this particular nematode relies on nematicides such as 1,3-Dichloropropene (Telone) at 40 gpa.or methyl bromide at 1000 lb/ac to control to 28 in deep.
Tylenchulus semipenetrans, also known as the citrus nematode or citrus root nematode, is a species of plant pathogenic nematodes and the causal agent of slow decline of citrus. T. semipenetrans is found in most citrus production areas and diverse soil textures worldwide. Their feeding strategy is semi-endoparasitic and has a very narrow host range among commonly grown crops. These nematodes are considered as major plant-parasitic nematode because they can cause 10-30% losses reported on citrus trees. They also parasitize other hosts such as olive, grape, persimmon and lilac. The citrus nematode was first discovered in California in 1913 by J. R. Hodges, a horticultural inspector for Los Angeles County, and was later described and named by Nathan Cobb that year. T. semipenetrans is the only species of Tylenchulidae that are economically important to agriculture.
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.
Helicotylenchus is a genus of nematodes in the family Hoplolaimidae. They are known generally as spiral nematodes. They are found worldwide because they can live and survive in a wide range of habitats. They are among the most common parasitic nematodes of plants; found in corn, bananas, grass, soybeans.
Pratylenchus alleni is a migratory endoparasitic nematode, living inside of plant roots and feeding on parenchyma cells in the root cortex. P. alleni is an obligate biotroph, meaning it must have a living host in order to survive. Due to their incredibly broad host range, Pratylenchus species fall third in total economic impact, finishing just behind cyst nematodes and root knot nematodes (Meloidogyne). In Canada, it was isolated for the first time in 2011 in a soybean field.
Scutellonema bradys, also known as yam nematode, is a migratory endoparasitic nematode causing major damage to yam crop in many African tropical regions, as well in parts of South and Central America and Asia. They can cause reduction of 20-30% in tuber weight at harvest.