| 翻訳と辞書 |
| Bur oak blight ： ウィキペディア英語版 |
Bur oak blight
Bur oak blight (BOB) is a fungal disease that is relatively new to the plant pathogen landscape. BOB started to appear in Midwestern states in the 1990s. The first few diagnoses pointed to a common fungus, ''Tubakia dryina'', as the culprit. However upon further research BOB was said to be caused by a new unnamed species of ''Tubakia'', later named ‘’Tubakia iowensis T.C. Harr. & D. McNew sp. nov. ‘’ BOB has severe symptoms and is a serious new problem amidst the plant pathology world.
==Hosts and symptoms==
The host for this disease is the bur oak, ''Quercus macrocarpa''. Research shows that ''Q. macrocarpa var. olivaeformis'' tends to be the most susceptible to the pathogen, but the more common and widespread ''Q. macrocarpa var. macrocarpa'' has also been affected by BOB. ''Q. macrocarpa var. olivaeformis'' has a range centered in the state of Iowa and is characterized by acorns that are olive shaped and smaller than the acorns of other susceptible varieties.〔Deitschmann GH. 1965. Bur oak (Quercus macrocarpa Michx.). In: Fowells HA, comp. 1965. Silvics of forest trees of the United States. USDA, Handbook 271. Washington DC. p 563–568.〕 The range of BOB is centered in the state of Iowa, however, it has also recently been confirmed in southern Minnesota.
When affected by the disease, the oak develops vein necrosis confined to the leaf midvein and major lateral veins, eventually causing leaf death. Symptoms typically start in the lower crown of the tree and eventually spread to the entire tree.〔Engelbrecht, C., and A. Flickinger. "What’s happening to Iowa’s bur oaks." Iowa State University Extension, Hort & Home Pest News IC-497 (21) 22 (2007): 8-22.〕 If this disease persists for many years, there can be lasting effects. One example is the possible loss of food reserves. This can leave the tree susceptible to greater insect predation, secondary infections from other pathogens, and death. A distinguishing characteristic of ''T. iowensis'' is the formation of black crustose asexual fruiting bodies at the base of the petioles that are retained until the following year. These distinctive fruiting bodies are pycnothyria (conidiomata) with radiating setae-like hyphae that form along the necrotic veins.
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
■ウィキペディアで「Bur oak blight」の詳細全文を読む
スポンサード リンク
| 翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|