The following is a list of diseases of pears (Pyrus communis).
Bacterial diseases | |
---|---|
Crown gall | Agrobacterium tumefaciens |
Fire blight | Erwinia amylovora |
Pseudomonas blossom blast and canker | Pseudomonas syringae pv. syringae |
Pear decline | Phytoplasma |
Fungal diseases | |
---|---|
Alternaria fruit rot | Alternaria spp. |
Anthracnose canker and bull's-eye rot | Pezicula malicorticus |
Armillaria root rot (shoestring root rot) | Armillaria mellea |
Bitter rot | Glomerella cingulata |
Black rot, leaf spot and canker | Botryosphaeria obtusa |
Black spot (of Japanese pear) | |
Blister canker | |
Blister disease | Coniothecium chomatosporum |
Blue mold rot | |
Botrytis spur and blossom blight | Botrytis cinerea |
Brown rot | |
Cladosporium fruit rot | Cladosporium herbarum |
Clitocybe root rot (mushroom root rot) | |
Coprinus rot | |
Dematophora root rot (Rosellinia root rot) | Rosellinia necatrix |
Diplodia canker | Botryosphaeria stevensii |
Elsinoe leaf and fruit spot | Elsinoe piri |
European canker | Nectria galligena |
Fabraea leaf and fruit spot | Diplocarpon mespili |
Fly speck | Schizothyrium pomi |
Gibberella canker | Gibberella baccata |
Gray mold rot | |
Late leaf spot | |
Mucor fruit rot | Mucor spp. |
Mycosphaerella leaf spot (ashy leaf spot and fruit spot) | Mycosphaerella pyri |
Nectria twig blight (coral spot) | Nectria cinnabarina |
Pear scab | Venturia pyrina |
Perennial canker | Neofabraea perennans |
Phyllosticta leaf spot | Phyllosticta sp. |
Phytophthora crown and root rot (sprinkler rot) | |
Pink mold rot | |
Powdery mildew | |
Pythium dieback | Pythium spp. |
Rhizopus rot | |
Rust, American hawthorne | |
Rust, Kern's pear | |
Rust, Pacific Coast pear | |
Rust, pear trellis (European pear rust) | |
Rust, Rocky Mountain pear | |
Side rot | |
Silver leaf | |
Sooty blotch | |
Thread blight (Hypochnus leaf blight) | Corticium stevensii |
Valsa canker | Valsa ceratosperma |
Wood rot | Trametes versicolor |
Xylaria root rot | Xylaria spp. |
Miscellaneous diseases and disorders | |
---|---|
Alfalfa greening (green stain) | Unknown |
Bitter pit | Localized calcium deficiency |
Black end | Water imbalance |
Black speck (skin speckling) | Associated with low oxygen in storage |
Blossom blast | Boron deficiency |
Brown core | High CO2 |
Core breakdown (Bartlett) | Senescence |
Cork spot | Associated with calcium deficiency |
Green stain | Unknown |
Internal bark necrosis | Unknown |
Mealy core (d`Anjou) | Senescence |
Pink end (Bartlett) | Preharvest low temperature |
Rosette | Unknown |
Scald | Senescence |
Nematodes, parasitic | |
---|---|
Dagger, American | |
Dagger | |
Lesion | |
Pin | Paratylenchus spp. |
Root-knot | Meloidogyne spp. |
Viruslike diseases | |
---|---|
Flemish beauty corky pit | Virus suspected |
Pear blister canker | Virus suspected |
Pear decline | Phytoplasma |
Pear freckle pit | Virus suspected |
Pear red mottle | Virus suspected |
Pear ring pattern mosaic | Virus suspected |
Pear rough bark | Virus suspected |
Pear stony pit | Virus suspected |
Pear vein yellows | Virus suspected |
Quince bark necrosis | Virus suspected |
Quince sooty ring spot | Virus suspected |
Quince stunt | Virus suspected |
Quince yellow blotch | Virus suspected |
Coronary artery disease (CAD), also called coronary heart disease (CHD), ischemic heart disease (IHD), myocardial ischemia, or simply heart disease, involves the reduction of blood flow to the heart muscle due to build-up of plaque (atherosclerosis) in the arteries of the heart. It is the most common of the cardiovascular diseases. Types include stable angina, unstable angina, myocardial infarction, and sudden cardiac death. A common symptom is chest pain or discomfort which may travel into the shoulder, arm, back, neck, or jaw. Occasionally it may feel like heartburn. Usually symptoms occur with exercise or emotional stress, last less than a few minutes, and improve with rest. Shortness of breath may also occur and sometimes no symptoms are present. In many cases, the first sign is a heart attack. Other complications include heart failure or an abnormal heartbeat.
The Centers for Disease Control and Prevention (CDC) is the national public health agency of the United States. It is a United States federal agency, under the Department of Health and Human Services, and is headquartered in Atlanta, Georgia.
A disease is an abnormal condition that negatively affects the structure or function of all or part of an organism, and that is not immediately due to any external injury. Diseases are often known to be medical conditions that are associated with specific signs and symptoms. A disease may be caused by external factors such as pathogens or by internal dysfunctions. For example, internal dysfunctions of the immune system can produce a variety of different diseases, including various forms of immunodeficiency, hypersensitivity, allergies and autoimmune disorders.
Tuberculosis (TB) is an infectious disease usually caused by Mycobacterium tuberculosis (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in which case it is known as latent tuberculosis. Around 10% of latent infections progress to active disease which, if left untreated, kill about half of those affected. Typical symptoms of active TB are chronic cough with blood-containing mucus, fever, night sweats, and weight loss. It was historically referred to as consumption due to the weight loss associated with the disease. Infection of other organs can cause a wide range of symptoms.
An infection is the invasion of an organism's body tissues by disease-causing agents, their multiplication, and the reaction of host tissues to the infectious agents and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable disease, is an illness resulting from an infection.
Huntington's disease (HD), also known as Huntington's chorea, is a neurodegenerative disease that is mostly inherited. The earliest symptoms are often subtle problems with mood or mental abilities. A general lack of coordination and an unsteady gait often follow. It is also a basal ganglia disease causing a hyperkinetic movement disorder known as chorea. As the disease advances, uncoordinated, involuntary body movements of chorea become more apparent. Physical abilities gradually worsen until coordinated movement becomes difficult and the person is unable to talk. Mental abilities generally decline into dementia. The specific symptoms vary somewhat between people. Symptoms usually begin between 30 and 50 years of age but can start at any age. The disease may develop earlier in each successive generation. About eight percent of cases start before the age of 20 years, and are known as juvenile HD, which typically present with the slow movement symptoms of Parkinson's disease rather than those of chorea.
Diarrhea, also spelled diarrhoea, is the condition of having at least three loose, liquid, or watery bowel movements each day. It often lasts for a few days and can result in dehydration due to fluid loss. Signs of dehydration often begin with loss of the normal stretchiness of the skin and irritable behaviour. This can progress to decreased urination, loss of skin color, a fast heart rate, and a decrease in responsiveness as it becomes more severe. Loose but non-watery stools in babies who are exclusively breastfed, however, are normal.
Crohn's disease is a type of inflammatory bowel disease (IBD) that may affect any segment of the gastrointestinal tract. Symptoms often include abdominal pain, diarrhea, fever, abdominal distension, and weight loss. Complications outside of the gastrointestinal tract may include anemia, skin rashes, arthritis, inflammation of the eye, and fatigue. The skin rashes may be due to infections as well as pyoderma gangrenosum or erythema nodosum. Bowel obstruction may occur as a complication of chronic inflammation, and those with the disease are at greater risk of colon cancer and small bowel cancer.
Coeliac disease is a long-term autoimmune disorder, primarily affecting the small intestine, where individuals develop intolerance to gluten, present in foods such as wheat, rye and barley. Classic symptoms include gastrointestinal problems such as chronic diarrhoea, abdominal distention, malabsorption, loss of appetite, and among children failure to grow normally. This often begins between six months and two years of age. Non-classic symptoms are more common, especially in people older than two years. There may be mild or absent gastrointestinal symptoms, a wide number of symptoms involving any part of the body, or no obvious symptoms. Coeliac disease was first described in childhood; however, it may develop at any age. It is associated with other autoimmune diseases, such as Type 1 diabetes mellitus and Hashimoto's thyroiditis, among others.
Lyme disease, also known as Lyme borreliosis, is a vector-borne disease caused by the Borrelia bacterium, which is spread by ticks in the genus Ixodes. The most common sign of infection is an expanding red rash, known as erythema migrans, which appears at the site of the tick bite about a week afterwards. The rash is typically neither itchy nor painful. Approximately 70–80% of infected people develop a rash. Early diagnosis can be difficult. Other early symptoms may include fever, head aches and tiredness. If untreated, symptoms may include loss of the ability to move one or both sides of the face, joint pains, severe headaches with neck stiffness or heart palpitations. Months to years later repeated episodes of joint pain and swelling may occur. Occasionally shooting pains or tingling in the arms and legs may develop. Despite appropriate treatment about 10 to 20% of those affected develop joint pains, memory problems and tiredness for at least six months.
Cardiovascular disease (CVD) is a class of diseases that involve the heart or blood vessels. CVD includes coronary artery diseases (CAD) such as angina and myocardial infarction. Other CVDs include stroke, heart failure, hypertensive heart disease, rheumatic heart disease, cardiomyopathy, abnormal heart rhythms, congenital heart disease, valvular heart disease, carditis, aortic aneurysms, peripheral artery disease, thromboembolic disease, and venous thrombosis.
Alzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems with language, disorientation, mood swings, loss of motivation, self-neglect, and behavioral issues. As a person's condition declines, they often withdraw from family and society. Gradually, bodily functions are lost, ultimately leading to death. Although the speed of progression can vary, the typical life expectancy following diagnosis is three to nine years.
Sexually transmitted infections (STIs), also referred to as sexually transmitted diseases (STDs) and the older term venereal disease, are infections that are spread by sexual activity, especially vaginal intercourse, anal sex and oral sex. STIs often do not initially cause symptoms, which results in a risk of passing the infection on to others. Symptoms and signs of STIs may include vaginal discharge, penile discharge, ulcers on or around the genitals, and pelvic pain. Some STIs can cause infertility.
An autoimmune disease is a condition arising from an abnormal immune response to a functioning body part. There are at least 80 types of autoimmune diseases. Nearly any body part can be involved. Common symptoms include low grade fever and feeling tired. Often symptoms come and go.
Lupus, technically known as systemic lupus erythematosus (SLE), is an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue in many parts of the body. Symptoms vary between people and may be mild to severe. Common symptoms include painful and swollen joints, fever, chest pain, hair loss, mouth ulcers, swollen lymph nodes, feeling tired, and a red rash which is most commonly on the face. Often there are periods of illness, called flares, and periods of remission during which there are few symptoms.
Sickle cell disease (SCD) is a group of blood disorders typically inherited from a person's parents. The most common type is known as sickle cell anaemia. It results in an abnormality in the oxygen-carrying protein haemoglobin found in red blood cells. This leads to a rigid, sickle-like shape under certain circumstances. Problems in sickle cell disease typically begin around 5 to 6 months of age. A number of health problems may develop, such as attacks of pain, anemia, swelling in the hands and feet, bacterial infections and stroke. Long-term pain may develop as people get older. The average life expectancy in the developed world is 40 to 60 years.
Cirrhosis, also known as liver cirrhosis or hepatic cirrhosis, and end-stage liver disease, is the impaired liver function caused by the formation of scar tissue known as fibrosis due to damage caused by liver disease. Damage causes tissue repair and subsequent formation of scar tissue, which over time can replace normal functioning tissue, leading to the impaired liver function of cirrhosis. The disease typically develops slowly over months or years. Early symptoms may include tiredness, weakness, loss of appetite, unexplained weight loss, nausea and vomiting, and discomfort in the right upper quadrant of the abdomen. As the disease worsens, symptoms may include itchiness, swelling in the lower legs, fluid build-up in the abdomen, jaundice, bruising easily, and the development of spider-like blood vessels in the skin. The fluid build-up in the abdomen may become spontaneously infected. More serious complications include hepatic encephalopathy, bleeding from dilated veins in the esophagus, stomach, or intestines, and liver cancer.
Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms become more common. The most obvious early symptoms are tremor, rigidity, slowness of movement, and difficulty with walking. Cognitive and behavioral problems may also occur with depression, anxiety, and apathy occurring in many people with PD. Parkinson's disease dementia becomes common in the advanced stages of the disease. Those with Parkinson's can also have problems with their sleep and sensory systems. The motor symptoms of the disease result from the death of cells in the substantia nigra, a region of the midbrain, leading to a dopamine deficit. The cause of this cell death is poorly understood, but involves the build-up of misfolded proteins into Lewy bodies in the neurons. Collectively, the main motor symptoms are also known as parkinsonism or a parkinsonian syndrome.
The COVID-19 pandemic, also known as the coronavirus pandemic, is an ongoing global pandemic of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The novel virus was first identified from an outbreak in the Chinese city of Wuhan in December 2019, and attempts to contain it there failed, allowing it to spread across the globe. The World Health Organization (WHO) declared a Public Health Emergency of International Concern on 30 January 2020 and a pandemic on 11 March 2020. As of 12 March 2022, the pandemic had caused more than 455 million cases and 6.03 million deaths, making it one of the deadliest in history.
Coronavirus disease 2019 (COVID-19) is a contagious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The first known case was identified in Wuhan, China, in December 2019. The disease has since spread worldwide, leading to an ongoing pandemic.