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What is leaf curl disease in geranium viral diseases
There are many types of geranium viral diseases. The following common ones are mainly distributed in Europe and the Americas, with a few reports also in Asia. Geranium leaf curl disease is also known as geranium crinkle leaf disease. [Pathogen] Pelargonium leaf curl virus (Pelargoniumleafcurlvirus, PLCV), thermal death point 85-90°C. [Symptoms] Chlorotic spots appear on young leaves, then develop into yellow round or star-shaped spots with a dark yellow center and a pale halo around them, along with necrotic perforation
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A Detailed Guide to Common Geranium Diseases and Their Control Methods
The main diseases of geraniums include: ① Leaf spot disease. In the early stage, needle-tip-sized, round or irregular small brown spots appear on the leaves, which gradually expand into dark brown or reddish-brown lesions. In severe cases, the entire leaf is covered with lesions until it dries up and falls off; the stems and branches also turn black, shrink and rot, and even the leaves on the stems wither and die, leaving only a few leaves at the top. Preventive measures: a. When cultivating in a greenhouse, do not plant too densely, and pay attention to frequent ventilation and light exposure; b. When watering, avoid pouring water onto the plants and avoid splashing water droplets
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Symptoms and Control Methods of Common Leaf Spot Diseases in Geraniums
Geranium leaf spot disease is a common disease in spring and summer. It is most likely to occur in hot and rainy seasons, often causing most of the infected leaves to die and drop off. When the stem is infected, it turns black, wilts and rots; cutting open the base reveals brown or black vascular bundles. Affected cuttings fail to root, with rot starting from the stem and developing upward, causing leaves to wilt and die. Symptoms: Geranium leaf spot disease includes two types: black spot disease and brown spot disease. Black spot disease: initial water-soaked spots appear on leaves, semicircular to irregular in shape, later becoming circular, 2 to 3 mm in diameter,
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What types of silkworm diseases are there? A full analysis of common types
Silkworm diseases can be divided into two categories: one is infectious diseases, and the other is non-infectious diseases. Any disease caused by pathogenic microorganisms such as viruses, bacteria, and fungi invading the silkworm body and then multiplying is an infectious disease. It can be transmitted from diseased silkworms to healthy silkworms and is an important factor affecting sericulture production. Any disease of silkworms caused by attacks by arthropods (fly maggots, lice mites), pesticide poisoning, and mechanical trauma is called a non-infectious disease. It cannot cause healthy silkworms to become ill through silkworms as a medium, and it is also an important factor affecting sericulture production.
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What is the difference between the two rice diseases? Explained clearly in one article
In recent years, bacterial brown spot of rice has shown a trend of relatively severe occurrence in some rice areas of our province. Most farmers mistakenly treat this disease as rice blast, which both increases costs and fails to achieve good results. For this reason, the two diseases are specifically distinguished below. 1. Symptoms. The symptoms of bacterial brown spot of rice are that reddish-brown small spots first appear on the upper leaves of the rice starting from the leaf tip and leaf edge, then expand into spindle-shaped, long oval, or irregular strip-like streaks, gradually spreading to the entire leaf, causing local necrosis of the leaf, with no bacterial ooze visible
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How are common diseases of Silkie chickens diagnosed? With a detailed explanation of rearing methods
1. Newcastle disease (fowl pest) [Diagnosis] Sick chickens are listless, have reduced appetite, elevated body temperature, tremors, head tilted backward, opisthotonus, and circular movement, etc. Difficulty breathing, drooping wings, greenish watery droppings, death after 2 to 3 days, with a relatively high mortality rate. [Treatment] At 7 to 8 days of age, chicks are given Newcastle disease strain II vaccine by nasal or eye drops; at 28 days of age, the vaccine is administered once more; at 50 to 60 days of age, Newcastle disease strain I vaccine is injected intramuscularly. If the disease breaks out suddenly, Newcastle disease strain I vaccine should immediately be injected intramuscularly.
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How to prevent and control non-physiological diseases of mushrooms?
(1) Deformed mushrooms Deformed mushrooms are mostly induced by temperature differences or unfavorable environments; they may also be related to the strain used. Deformities mainly include the following types: 1. Hollow stipe. Mushrooms on the bed look normal, but when the base is cut off, part of the stipe is found to be hollow, usually with a ring-shaped cavity around a hard core. Afterwards, the cut surface of the stipe may crack and then curl backward, causing the mushrooms to lose their appealing appearance and decline in quality. This is mainly caused by low air humidity during the fruiting period, rapid evaporation of water from the mushroom bodies, excessively dry casing soil, and the fruiting bodies being unable to obtain water.
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What are the two main diseases of carnations?
Carnations are most susceptible to leaf spot and stem wilt, and calyx rot. The fungal spores of leaf spot and stem wilt persist in carnation plants and in decayed, rotting plants, and spread through the air. When water remains on the plant surface for 8-10 consecutive hours, the pathogen can penetrate through the moisture. The symptoms of leaf spot and stem wilt are: grayish-brown leaves or spots with purple edges appearing on the petals. The spots are formed by clusters of black spores, and the stems begin to yellow and wither from the internodes, then develop into a wilt that encircles the stem completely. The pathogen of calyx rot persists in the old leaves, lower stems and branches, or decayed and rotting plants of carnations. High
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Symptom Identification and Control Methods of Carnation Viral Diseases
Carnation viral disease is a worldwide disease, occurring in all cultivation regions. The common viral diseases are vein mottle disease, necrotic spot disease, etched ring disease, and latent disease. Viruses often cause carnations to grow weakly, with short flower stems, smaller flowers, mottled petals, and split calyces, severely affecting the quality and yield of cut flowers. (1) Carnation necrotic spot disease: the middle leaves of infected plants turn grayish-white, showing pale yellow necrotic mottling, or irregularly shaped streaks or stripes. The lower leaves often show purplish-red streaks or stripes. As the plant
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A Detailed Guide to Controlling the 3 Major Diseases of Carnations
Leaf spot, Fusarium wilt and viral diseases are the main diseases that occur on carnations. The control methods are as follows: Leaf spot mainly infects the leaves, and the disease usually starts on the lower leaves. On severely affected plants the diseased parts are distorted, and the diseased leaves wither, droop and hang down over the stem, but do not fall off. Old leaves are affected more often and more severely, while new leaves are affected less, and the disease occurs more in open-field cultivation than in greenhouses. Control methods: start spraying regularly from the early stage of the disease; spray a fungicide immediately after disbudding and cutting flowers for protection. A 75% chlorothalonil wettable powder solution diluted 800 to 1000 times can be used for spraying
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