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How to prevent and control bacterial leaf spot in geraniums?
Geranium, also known as zonal geranium, fish geranium and horseshoe geranium. Native to South Africa. It prefers cool conditions, fears high temperatures, and is not cold-tolerant either. It requires ample sunlight. It is not tolerant of waterlogging but is slightly tolerant of drought, and prefers well-drained, fertile loam. In spring and autumn, when the weather is cool, conditions are most suitable for the growth of geraniums. In winter, indoors at around 15°C during the day and no lower than 5°C at night, with sufficient light maintained, they can bloom continuously. In hot summers, the plants enter a dormant or semi-dormant state, so they should be placed in partial shade and watering should be carefully controlled. It is resistant to chlorine. Plants of the genus Pelargonium are important potted flowers. Cultivation is extremely
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Symptoms and Control Methods of Carnation Leaf Spot Disease
There are many types of pests and diseases that harm carnations, and unsuitable cultivation environments and management mistakes can both aggravate pests and diseases. Carnation leaf spot disease, also known as carnation white star disease, can harm many flowers of the Caryophyllaceae family. [Pathogen] Septoria dianthi Desm., belonging to the fungi Deuteromycotina, genus Septoria. [Symptoms] The disease harms leaves and stems. Nearly round small spots form on leaves and stems, with a diameter of about 5 mm; the spots are light brown with purple edges,
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What is the fungal leaf spot disease of cut-flower carnations?
Symptoms: purple round spots 0.5-1.5 cm in diameter, surrounded by a yellow-green margin; the centers of the spots then turn brownish-gray and dry out, and finally the lesions enlarge, black spores appear, and the leaves begin to yellow and drop. Causes: watering from above the plant, poor ventilation, excessively high humidity at night, and overwatering and overfertilizing after planting are also among the causes of the disease. Control methods: keep the plants as dry as possible, preferably use drip irrigation, and maintain good ventilation. Use 1% Bordeaux mixture or 75% chlorothalonil wettable powder at 500 times dilution,
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What are the control methods for Dianthus leaf spot?
Identification points: Dianthus leaf spot mainly affects the leaves. Leaf spots are initially yellow, gradually becoming dark brown round to oval spots, and later the spots turn grayish brown with dark brown edges; in severe cases the spots join together, causing the leaves to turn yellow, wither and drop early. Under humid conditions, many small black granules appear beneath the spots, namely the conidia and conidiophores of the pathogen. Occurrence characteristics: a fungal disease. It can occur year-round in greenhouses. Under conditions such as abundant rain, heavy fog and heavy dew, the disease occurs easily. Poor ventilation and light transmission, extensive management and weak plant growth can all
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How to control leaf spot disease in hydrangea (Impatiens)
[Alias] Impatiens brown spot disease. Hydrangea leaf spot is one of the common diseases on hydrangea. [Distribution] Sichuan, Henan, Guangdong, Taiwan, China, Jilin, Shanghai, Zhejiang, Hunan and other places. [Symptoms] The disease mainly occurs on leaves. Leaf spots initially appear as light yellowish-brown water-soaked small dots, then expand into circular or nearly circular shapes, 2-5 mm in diameter, with a maximum of about 15 mm. Later the center becomes light brown, the edge dark brown, slightly raised, with inconspicuous concentric rings, and black small dots, which are the fungus's pycnidia, are produced on the diseased area. In severely infected
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Symptom Identification and Control Methods for Licorice Gray Leaf Spot
It damages the leaves, forming nearly round brown lesions with gray centers. Control methods: (1) Clear the garden in winter and dispose of plant debris. (2) During the disease period, spray 1:1:120 Bordeaux mixture or 70% thiophanate-methyl wettable powder at 1500-2000 times dilution.
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Symptoms and Control Methods of Bacterial Leaf Spot in Lilies
Bacterial leaf spot is an important disease of lilies, occurring and distributed in certain regions, and can develop both under protected cultivation and in open fields. Typically 5%-10% of plants are affected, impacting yield and quality to some extent. In severely affected plots, the field incidence rate can reach over 20%, significantly affecting lily production. [Symptoms] This disease can affect all parts of the lily, with symptoms mostly appearing on above-ground parts. Initially, densely packed water-soaked greenish-brown nearly oval small spots appear on the leaves, which later develop into nearly spindle-shaped yellowish-brown to dark brown necrotic lesions, slightly sunken, with water-soaked edges
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Annam leaf turtle spotted in the wild for the first time in 65 years
Researchers with the Asian Turtle Program have announced that late last month, in a wild area of Quang Nam Province, Vietnam, they captured an Annam leaf turtle, a species listed by the International Union for Conservation of Nature as one of the world's 25 most endangered turtles. It is said that the blood of the Annam leaf turtle can be used as a traditional medicine for treating heart disease. This year Vietnam passed a new law stating that it is illegal for anyone to keep or sell an Annam leaf turtle. The Asian Turtle Program is running an education and awareness campaign in Quang Nam Province, Vietnam, to guide people toward understanding the importance of protecting the Annam leaf turtle
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Symptoms and Control Methods of Primula Leaf Spot Disease
Symptoms: It mainly affects the leaves of the plant. The disease spreads from the lower part of the plant to the upper part. The spots are usually 3 to 4 mm in diameter and brown; in severe cases, the diseased leaves wither and die, causing defoliation (see Figure 2). The disease is caused by Ramularia primulae. The pathogen overwinters as mycelium or conidiomata on diseased plant debris, and seeds can also carry the pathogen, becoming the primary infection source for the following year. The disease mainly spreads through conidia carried by air and rainwater. Reinfection is frequent during the growing season. Plants are usually prone to the disease in warm, humid weather and when nitrogen fertilizer is applied excessively.
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What are the control methods for primrose leaf spot disease?
Symptoms The disease occurs on the leaves. The spots are usually 3-4 mm in diameter and brown; in severe cases, the diseased leaves wither and die, causing defoliation. The disease spreads from the lower leaves to the upper leaves. The pathogen is Ramularia primulae Thumen, the primrose Ramularia fungus. It belongs to the Deuteromycotina fungi. The conidiophores emerge from the stomata, growing in clusters of several branches, very short, unbranched, colorless, with slightly curved tips; the conidia are cylindrical or short club-shaped, single-celled or two-celled, colorless, measuring 16-24 x 3-4 micrometers. Transmission routes and conditions for disease development
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