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.

Morphology and biology

Potato rot nematodes are microscopic worms approximately 1.4 millimetres long. Their life cycle takes place inside 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...

 tubers where they eat starch

Starch

Starch or amylum is a carbohydrate consisting of a large number of glucose units joined together by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store...

 grains. This causes the affected tissues to becomes brown and powdery and the surface of the tuber to become covered with dark patches with dry cracking skin. The nematodes live inside the living tissue where they aggregate rapidly as the fecund females each produce up to 250 eggs. They survive in stored tubers during the winter and can infect the stolon

Stolon

In biology, stolons are horizontal connections between organisms. They may be part of the organism, or of its skeleton; typically, animal stolons are external skeletons.-In botany:...

s of planting material. The soil plays only a secondary role in the transfer of this nematode.

Ecology

This species is cosmopolitan and found throughout all the climatic zones where potatoes are cultivated. It is unable to withstand desiccation and is usually only important in cool, moist soils. It is not restricted to the potato and is able to survive on other host plants including garlic

Garlic

Allium sativum, commonly known as garlic, is a species in the onion genus, Allium. Its close relatives include the onion, shallot, leek, chive, and rakkyo. Dating back over 6,000 years, garlic is native to central Asia, and has long been a staple in the Mediterranean region, as well as a frequent...

, onion

Onion

The onion , also known as the bulb onion, common onion and garden onion, is the most widely cultivated species of the genus Allium. The genus Allium also contains a number of other species variously referred to as onions and cultivated for food, such as the Japanese bunching onion The onion...

, beet

Beet

The beet is a plant in the Chenopodiaceae family which is now included in Amaranthaceae family. It is best known in its numerous cultivated varieties, the most well known of which is the purple root vegetable known as the beetroot or garden beet...

, carrot

Carrot

The carrot is a root vegetable, usually orange in colour, though purple, red, white, and yellow varieties exist. It has a crisp texture when fresh...

, 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...

, cucumber

Cucumber

The cucumber is a widely cultivated plant in the gourd family Cucurbitaceae, which includes squash, and in the same genus as the muskmelon. The plant is a creeping vine which bears cylindrical edible fruit when ripe. There are three main varieties of cucumber: "slicing", "pickling", and...

, pumpkin

Pumpkin

A pumpkin is a gourd-like squash of the genus Cucurbita and the family Cucurbitaceae . It commonly refers to cultivars of any one of the species Cucurbita pepo, Cucurbita mixta, Cucurbita maxima, and Cucurbita moschata, and is native to North America...

, watermelon

Watermelon

Watermelon is a vine-like flowering plant originally from southern Africa. Its fruit, which is also called watermelon, is a special kind referred to by botanists as a pepo, a berry which has a thick rind and fleshy center...

, eggplant, pepper

Bell pepper

Bell pepper, also known as sweet pepper or a pepper and capsicum , is a cultivar group of the species Capsicum annuum . Cultivars of the plant produce fruits in different colors, including red, yellow, orange and green. Bell peppers are sometimes grouped with less pungent pepper varieties as...

, bulbous iris

Iris (plant)

Iris is a genus of 260-300species of flowering plants with showy flowers. It takes its name from the Greek word for a rainbow, referring to the wide variety of flower colors found among the many species...

, clover

Clover

Clover , or trefoil, is a genus of about 300 species of plants in the leguminous pea family Fabaceae. The genus has a cosmopolitan distribution; the highest diversity is found in the temperate Northern Hemisphere, but many species also occur in South America and Africa, including at high altitudes...

 and groundnuts

Peanut

The peanut, or groundnut , is a species in the legume or "bean" family , so it is not a nut. The peanut was probably first cultivated in the valleys of Peru. It is an annual herbaceous plant growing tall...

. Altogether, about 70 crops and weeds have been recorded as hosts along with a similar number of species of fungus.

External links

• Nemaplex, University of California - Ditylenchus destructor