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Garlic Bloat Nematode

Garlic bloat nematode, which is also known as a bulb and stem nematode, causes bloated, twisted, swollen leaves, and distorted and cracked bulbs with dark rings.

garlic bloat nematode
Garlic Bloat Nematode
Courtesy of Sandra Jensen,
Cornell University,

Infestation with this nematode can weaken plants, causing them to be susceptible to secondary infections. Presence of this pest can affect export of the infested crop. Besides being a concern in garlic, this nematode can also affect other Allium species, such as leeks, onions, and chives, as well as other crops and plants including flower bulb crops, iris and gladiolus, and nightshades. The nematode can overwinter in the soil, and can be moved throughout the field on farming equipment, shoes, etc. Management recommendations include destruction of dry plant debris which can harbor the nematode, management of nightshade near crops, crop rotation away from Allium species on a four year cycle, good sanitation practices, use of bio-fumigant cover crops, and chemical fumigants.

You can submit plant samples for identification of boxwood blight to the University of New Hampshire Plant Diagnostic Lab. UNH Cooperative Extension Plant Pathologist Cheryl Smith asks growers to please call her at (603) 862-3841 for sampling instructions and to let her know they are sending samples. Samples should be either brought in or shipped overnight via Fed Ex or UPS. The PDF of the lab sample formpdf file, is also available on the website.

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NH Department of Agriculture, Markets and Food
Mailing: PO Box 2042, Concord NH 03302 -2042
Physical: 25 Capitol Street, Second Floor, Concord, NH 03301
(603) 271-3551 | fax: (603) 271-1109