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Onion _Bulb_ - Onion _dry bulb_

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					Onion (dry bulb-storage)
                                                                  Allium cepa (Alliaceae)

Fast Facts:
                Acres in Washington: Storage: 21,000 acres in 2006
                Per Acre Value: $2800
                Value of production in Washington: Storage: $132,840 million in 2006
                Number of Growers: 100 in 2007
                Percent of Value of U.S. Production: 12%
              *Statistics provided by the Washington Agriculture Statistic Service


              Onions are the 20th most valuable commodity in the state of Washington

Description
of crop:
       Dry bulb onions are either storage or nonstorage and both types are grown in
       Washington. However, 95 percent of Washington onions are storage. Washington
       is the 3rd largest onion producer in the United States with 12 percent of the U.S.
       onion production. Eastern Washington has the top onion producing counties in the
       State. Any cultivar can produce a dry bulb or be harvested earlier for green
       onions; however, storage varieties generally are harvested dry after the tops have
       matured. Onions are a cool-season, shallow-rooted, biennial monocot. They have
       multiple layers of thick, dark, papery skins. Storage onions have a higher
       percentage of solids than non storage varieties and they are usually rich in sulfur
       containing compounds, which gives them a characteristic pungent odor. Both the
       growing and storage environments can affect onions pungency which tends to
       increase with higher temperatures and more time in storage. Onions are described
       as short, or long-day types. The long day varieties need 15 hours or more of
       daylight and the short-day varieties 12 hours or less for proper bulb formation.
       Storage onions are planted in the spring and are harvested in September or
       October; several months after nonstorage onions are harvested. Storage onions
       can be produced from seed, seedlings or sets, although planting from seed is the
       most common method. Storage onions can be stored for up to eight months.

Key pests:
      Weeds are the primary pests of onions, since onions have shallow roots, sparse
      foliage and are poor competitors for nutrients and light. The most significant
      weeds are lambsquarter, nightshade, pigweeds, and grasses. The most damaging
      insect pest affecting onions are thrips, which feed on the onion leaves. This
      includes both the Western flower thrips and onion thrips. Other pests include the
      onion maggot and the seed corn maggot. The stubby-root nematode is also a
      concern in Washington. Major diseases of onions involve neck rot, black mold,
      gray mold, white rot, pink root and the iris yellow spot virus. The iris yellow spot
      virus is vectored by onion thrips and can cause yellowing of the leaves and death
       of the plant. Gray mold neck rot can cause as much as a 50 percent loss in storage
       onions and is the leading cause of storage onion loss.

Key pesticides:
      Lambsquarter and nightshade are controlled with Goal; grasses are controlled
      with Poast or Select. Thrips can be controlled with Radiant, Azadiractin, Lannate,
      and Carzol which has been used in Washington under a Section 18 Emergency
      Exemption. Thrips can be suppressed systemically with Vydate. Iris yellow spot
      virus can be managed by controlling thrips. The onion maggot and the seed corn
      maggot are treated with Lorsban. Stubby-root nematode is controlled with soil
      fumigation and Vydate. Neck rot can be treated with Mancozeb, Bravo and
      Rovral. Black mold is a disease of onions in transit and storage. Proper drying
      and handling are necessary to control black mold. White rot can be controlled
      with soil fumigation using Vapam and irrigation management. Pink root is a soil
      borne pathogen propagated by wheat and corn. It can be controlled with soil
      fumigation.

Critical pest
control issues:
       Growers should manage old onion residue, practice volunteer control, and utilize
       crop rotation. Onion fields are commonly fumigated once during each rotation
       cycle. Thrips are becoming resistant to some commonly used chemicals however
       they can be deterred by overhead irrigation and the use of beneficial insects.
       Irrigation management is also important regarding bacterial soft rots. Growers
       should consider pest resistance when selecting their onion cultivars. Some
       varieties offer resistant to diseases such as pink root. Eliminating wheat residue
       and corn residue helps with maggot problems. Other IPM practices include field
       scouting, cull management, avoiding crop injuries during harvest, maintaining
       proper nutrition, and using good sanitation practices.

Expert contacts: Kerrick Bauman
                  L & L Farms
                 7222 Coyan Rd.
                 Connell WA 99326
                 509 546 1578

Location
of production:
      The largest storage onion production areas are in the Columbia Basin region in
      Grant, Franklin, Benton, and Adams counties. Other counties that storage onions
      are grown in include: Chelan, Clallam, Clark, Columbia, Ferry, Grays Harbor,
      Island, Jefferson, King, Kitsap, Kittitas, Lewis, Mason, Okanogan, Pend Oreille,
      Pierce, San Juan, Skagit, Snohomish, Spokane, Stevens, Thurston, Wahkiakum,
      Walla Walla, Whitman, Whatcom and Yakima.

				
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Description: The latest research shows that onions not only a tasty vegetable, but also a strong human bones. Scientists at the University of Bern, Switzerland have found that lab mice in onion each day, after eating, osteoporosis, significantly alleviate the problem. The study leader Rudolph? Bulunneisen, said: "a certain amount of food each day onions may also contribute to osteoporosis prevention and treatment of mankind." He said, according to estimated weight, at least by people every day need to eat 400 grams of onions in order to achieve the same effect.