| 翻訳と辞書 |
| Alternaria black spot of canola ： ウィキペディア英語版 |
Alternaria black spot of canola
Alternaria Black Spot of Canola or grey leaf spot is an ascomycete fungal disease caused by a group of pathogens including: ''Alternaria brassicae'', ''A. alternata'' and ''A. raphani''. This pathogen is characterized by dark, sunken lesions of various size on all parts of the plant, including the leaves, stem, and pods. Its primary economic host is canola. In its early stages it only affects the plants slightly by reducing photosynthesis, however as the plant matures it can cause damage to the seeds and more, reducing oil yield as well.
== Host and symptoms ==
The major canola species that are susceptible to Alternaria Black Spot include ''Brassica rapa'' and ''Brassica napus'' (which are modified forms of rapeseed or brown mustard). The Canola Council of Canada has reported that ''B. rapa'' is more susceptible to the disease than ''B. napus'', because the latter has leaf wax, which provides more tolerance to black spot disease.〔(black spot. Canola Council of Canada (2014, February 13). Retrieved October 17, 2014, from http://www.canolacouncil.org/canola-encyclopedia/diseases/alternaria-black-spot/ )〕
There are no macroscopic signs of the pathogen, however conidia and fungal hyphae can be observed microscopically inside lesions. Symptoms can be observed at every stage of the life cycle and on almost every part of the plant, including in the seedling stage on cotyledons and in later growth stages on leaves, leaf petiole, stem, flowers, pods and seeds. 〔 A characteristic symptom of the pathogen is the name itself: black spots. Brown, black or dark grey lesions, surrounded by a yellow halo can be observed on lower leaves during the beginning stages of infection and can vary in size from 1 to 20mm. 〔 Lesions can combine to cause leaf death and premature defoliation. 〔 (alternaria black spot in canola. (n.d.). Department of Agriculture and Food, Government of Western Australia. Retrieved October 17, 2014, from https://www.agric.wa.gov.au/mycrop/diagnosing-alternaria-black-spot-canola ) 〕 These lesions can vary in size and color, and can rapidly spread to upper leaves, stems, and pods in favorable conditions. Infected pods will show dark, sunken lesions. If the lesion is large enough to infect the pod early in the season, they may fail to fully develop, and drop to the ground. Severely spotted pods dry, shrink, and may split open prematurely, causing the shrunken,〔 discolored seeds inside to drop to the ground. 〔 (H., & Gent, D. (n.d.). Alternaria Black Spot. In High Plains IPM Guide (Canola & Mustard ed.) Accessed 10/21/2014 from http://wiki.bugwood.org/uploads/AlternariaBlackSpot-CanolaMustard.pdf ) 〕 Infection of the pods is the most economically concerning symptom of Alternaria black spot, because this is the part of the plant where the oil is produced.
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「Alternaria black spot of canola」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.
|
|