[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-513580-105":59,"doc-detail-513580-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","what-is-a-plant-disease","What Is a Plant Disease?","","Plant diseases are described as broad conditions in which a plant differs from a normal healthy plant in structure or function. The document explains that disease is not a fixed, tangible object but a harmful process driven by a causal agent, distinct from injuries and from normal life processes. It outlines why plant pathology studies both nature and control, introduces historical crop impacts, and emphasizes how disease names reflect the attacked plant, affected plant part, and the way it is affected.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":35,"@type":76,"position":81},"https://docshare.wps.com/document/healthcare/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/what-is-a-plant-disease/513580/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/what-is-a-plant-disease/513580.png","ImageObject",300,407,{"name":92,"@type":93},"Quinn Holloway","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-11-03","2026-10-06",true,{"@type":102,"interactionType":103,"userInteractionCount":44},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"What defines a plant disease in this document?","Question",{"text":112,"@type":113},"A plant disease is any condition where a plant differs from a normal healthy plant in either structure or function. It may show changes in size, branching, leaves, wilting, or failure to produce flowers or fruit.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"How is disease different from injury and normal life processes?",{"text":117,"@type":113},"The document states that disease is a process caused by some agent and involves physiological changes. It must be distinguished from injury and from normal processes like maturation and leaf dropping.",{"name":119,"@type":110,"acceptedAnswer":120},"What are the three key pieces of information used to name a plant disease?",{"text":121,"@type":113},"A plant disease name generally includes: (1) the plant attacked, (2) the plant part affected, and (3) how that part is affected. Examples include peach leaf curl and black stem rust of wheat.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},513580,1791389712,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":34,"category_name":35,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":44,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":139,"language":140,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":141,"faqs":142,"seo_title":143,"seo_description":67,"update_tm":144,"read_time":145,"preview_page_count":4},2336474466712,"https://ap-avatar.wpscdn.com/davatar_a8503ba1806abce46bf441b54a3ca4cd","# What Is a Plant Disease?\n\nTop 10 Crops in Washington  \nWheat(Triticum aestivum)Alfalfa(Medicago sativa)Apple(Malus sylvestris)Potato (Solanum tuberosum)Sugar beet (Beta vulgaris)Barley (Hordeum vulgare)Hops (Humulus lupulus)Peas (Pisum sativum)Mint(Mentha spp.)Asparagus (Asparagus officinalis)  \nPLANT DISEASESOtis C.Maloy,Extension Plant Pathologist  \nThere have been many attempts to define what a plant disease is but all definitions have to bequalified to some extent.A plant disease is not a tangible object as is an insect or a weed.Itdoes not have absolute,fixed dimensions but varies in its appearance in a great many ways.  \nBroadly defined,a plant disease is any condition in which a plant is different in some way froma normal(i.e.,healthy)plant in either structure or function.The diseased plant may be shorter,have more branches,or fewer leaves than normal-it differs in structure.It may wilt and dieprematurely,or not produce flowers or fruit-it differs in function.  \nPlant diseases affect all plants,crop and noncrop,to some extent.They generally cause minordamage but when all of the required interacting and contributing factors are present,they canbe catastrophic.Famines caused by blights and mildews are recorded from biblical times.Lateblight of potatoes led to the great famine in Ireland in the mid-1800s and chestnut blighteliminated American chestnut as a commercial tree in the United States in a few decades.Incommercial crops,even minor losses to disease can be serious.  \nThe relative occurrence of plant diseases in the Pacific Northwest is demonstrated in Table 1which lists the top ten crops in Washington.The table gives the number of plant diseasesreported on that crop in the United States and separates out the number of those diseases thathave occurred in the Pacific Northwest.For example,of 87 diseases reported on wheat in theUnited States,39 of them occur in the Pacific Northwest.  \nTABLE 1  \nNumber Diseases Reported in  \nN.W.U.S.39872166601935914522553150920256  \nThe science that has developed which deals with the nature and control of plant diseases iscalled plant pathology.Plant pathology also involves other sciences,such as mycology,bacteriology,plant physiology,nematology,etc.  \nEM 3540-Page 2  \nAlthough we sometimes refer to a disease as a condition,it is not a static,constant conditionbut an everchanging one.Disease is a process,a eries of changes in the plant,always caused bysome agent.It is physiological,affecting all or part of the functions of the plant.It is abnormalto the plant and not the normal termination of some particular function(for example,normaldropping of leaves).Diseases are always harmful to the plant in the long run even though therehave been attempts to benefit from certain diseases.Attempts have been made to put toeconomic use the virus-induced color break in tulip and the virus-caused shortening of internodesof cherries but have not succeeded.  \nThe causal agent of a disease has a prolonged influence as compared to the sudden,instantaneous effect of an injury.So we must distinguish between disease and injury.We mustalso not confuse normal life processes,such as maturation and falling of leaves,with diseases.One common confusion is that causal agent and disease are the same.Some believe that afungus,bacterium,or nematode is a disease but it is not.It is the causal agent of a disease.  \nThe agent causing a plant disease is called a plant pathogen whether the agent is living(parasitic)or nonliving(nonparasitic),but usually the term pathogen is restricted to the former.  \n# How Are Diseases Classified?\n\nPlant diseases can be classified or categorized in a number of ways.One of the earliest and stillpopular ways is to separate diseases on the basis of the crop affected.Thus,there are diseasesof tree fruits,small fruits,vegetables,forest trees,cereals and grasses,ornamentals,etc.Anothersystem is to categorize diseases on the basis of the causal agent.In this system we have fungusdiseases,bac","cbCaie0NLnL9Fz81","https://ap.wps.com/l/cbCaie0NLnL9Fz81","pdf",1369017,51,"English","# What Is a Plant Disease?\n# How Are Diseases Classified?\n# How Do Plants Work?","[{\"question\":\"What defines a plant disease in this document?\",\"answer\":\"A plant disease is any condition where a plant differs from a normal healthy plant in either structure or function. It may show changes in size, branching, leaves, wilting, or failure to produce flowers or fruit.\"},{\"question\":\"How is disease different from injury and normal life processes?\",\"answer\":\"The document states that disease is a process caused by some agent and involves physiological changes. It must be distinguished from injury and from normal processes like maturation and leaf dropping.\"},{\"question\":\"What are the three key pieces of information used to name a plant disease?\",\"answer\":\"A plant disease name generally includes: (1) the plant attacked, (2) the plant part affected, and (3) how that part is affected. Examples include peach leaf curl and black stem rust of wheat.\"}]","What Is a Plant Disease? | PDF",1791287378,129]