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Occurrence Patterns and Control Methods of Cherry Brown Spot Shot Hole Disease
Symptoms: Small brown, grayish-brown, or purplish-brown spots initially appear on the leaves, gradually forming circular lesions that are non-water-soaked and opaque, with no yellow-green halo around the lesions, 2-4 in diameter, with clear boundaries and a purplish-brown outer margin. In the later stage, the center turns white or brown, slightly zonate, and the lesions die and fall off, forming irregular shot holes. 2. Occurrence patterns: The pathogen overwinters on fallen leaves and spreads by wind and rain in the following spring. The disease begins in June, with the peak period from August to September. Heavy rainfall promotes disease occurrence and epidemic, and weakened tree vigor leads to severe disease. 3. Control methods:
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Occurrence Patterns and Control Methods of the White-Spotted Flower Chafer
The white-spotted flower chafer belongs to the order Coleoptera, family Cetoniidae, and is also known as the white-striped copper flower chafer, white-spotted flower chafer, white-spotted golden chafer, and copper chafer. It is distributed in Northeast China, North China, and the Huang-Huai-Hai region. When the white-spotted flower chafer damages crops, the market quality is greatly reduced in mild cases, and completely lost in severe cases, bringing relatively serious economic losses to growers. Hosts Currently, the hosts of the white-spotted flower chafer include corn, sunflower, tomato, watermelon, peach, grape, plum, strawberry, hop, the large composite weed bull thistle, willow, and elm. Damage characteristics The
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Occurrence Patterns and Control Methods of Cherry Blossom Pests and Diseases
Cherry blossom belongs to the genus Prunus in the rose family (Rosaceae). It has both the subtle fragrance of plum and the gorgeous beauty of peach, with as many as several hundred cultivars. In recent years, with the demand for landscape gardening, cherry blossoms have been widely used in gardens, adding much beautiful scenery to urban landscapes. However, cherry blossoms suffer from many pests and diseases, mainly the following: 1. Cherry blossom witches' broom disease. The symptom is that many short, thin branches emerge from the affected parts, resembling a bird's nest. On these branches, either no flowers or only a few flowers are produced, and the leaves on the branches are numerous and small. Each year, deformed branches increase at the affected parts.
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Occurrence and Integrated Control Methods of Sheep Nasal Bot Fly
Cause: Sheep nasal bot fly is a disease caused by the larvae of the sheep nasal bot fly parasitizing the nasal cavity of sheep, mainly affecting sheep (Ovis aries). The adult sheep nasal bot fly directly deposits larvae, and the larvae become adults after passing through the pupal stage. Adult sheep nasal bot flies appear from May to September each year. After mating, the male fly dies, and the female fly rests until the larvae inside her body develop before flying and becoming active, depositing maggots in the nostrils of sheep to breed larvae. The first-stage larvae attach to the nasal mucosa of sheep and gradually migrate inward, molting into second-stage larvae in the nasal cavity and frontal sinuses, and by the spring of the following year, they develop into mature third-stage larvae.
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Occurrence and Control of Panax notoginseng Leaf Rot
Symptoms This disease can harm all aboveground organs except the roots. The most typical symptom is the formation of black spindle-shaped lesions at the top of the petiole. When temperatures are high, the lesions rapidly encircle the petiole and quickly spread to the base of the leaflets, forming light black water-soaked lesions on the leaves with irregular edges. The diseased part of the petiole quickly softens, causing the upper leaflets to droop (commonly known as "twisted-down plate"). On the diseased areas, pale yellow powdery masses tinged with pink are often visible, which are the fruiting bodies of the pathogen. When attacking the middle of the leaf blade, it forms black irregular lesions with irregular edges,
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Analysis of the Occurrence of Canine Distemper and Preventive Measures
Canine distemper is a highly contagious infectious disease caused by the canine distemper virus, a member of the genus Morbillivirus in the family Paramyxoviridae. We analyzed a total of 55 cases of canine distemper and suspected cases diagnosed and treated from February to April 2003. The occurrence patterns were diverse and rather complex. They are reported below for reference. 1. Occurrence of canine distemper. 1.1 Causes of the disease. There are many and rather complex causes of this disease. According to the investigation, 22 cases (40%) developed the disease suddenly after being chilled from bathing
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Occurrence and Control Methods of Potato Tuber Rot Nematode
Fengning and Weichang counties in the north of Chengde City plant more than 40,000 hectares of potatoes annually, producing more than 800 million kg of seed potatoes and commercial potatoes per year, with about 120 million kg stored in winter, making it one of the four major potato production bases in the country. In recent years, the damage caused by the potato tuber rot nematode has led to great losses in stored potatoes. In 1994, it caused 5%-7% loss of stored potatoes, and in severely affected potato cellars, losses reached as high as 20%-30%. According to the currently retrieved data, this nematode is widely distributed in potato-growing areas of Asia, Europe, the Americas and Africa
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Occurrence Patterns and Control Methods of the Potato Tuber Moth
The potato tuber moth, also known as the potato borer and the tobacco leafminer, is commonly called the "string-skin worm," "embroidery worm," and "potato maggot" by farmers. 1. Damage symptoms: The larvae cause damage mainly by boring and feeding, usually entering through the buds and broken skin of the tubers. Larvae hatched on the plant spin silk and spread with the wind, boring from the leaf surface into the leaf interior to feed and cause damage. After the damaged leaves wither and die, the larvae move to other leaves to cause damage. 2. Occurrence patterns: The potato tuber moth produces several generations a year, overwintering in various stages on mother tubers in the field and on the residual plants and fallen leaves of various hosts. Adult
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How to prevent and control soybean anthracnose? Detailed explanation of occurrence patterns and control techniques
1 Disease symptoms A considerable portion of infected seeds die in the soil before emergence. The disease can occur from the seedling stage to the maturity stage. The pathogen can invade young stems from the cotyledons, damaging stems and pods, and also damaging leaves or petioles. 1.1 Cotyledon disease symptoms The disease can occur from the seedling stage to the maturity stage. On the emerged cotyledons there are dark brown lesions with slightly lighter edges. After the lesions expand, cracking or sunken areas often appear. When the climate is humid, the cotyledons become water-soaked and quickly wilt and fall off. 1.2 Leaf disease symptoms When leaves are infected, the lesions are irregular in shape, with dark
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How to prevent and control soybean phytophthora root rot? Detailed explanation of occurrence patterns and control methods
After soybean phytophthora root rot was introduced into our prefecture with the transfer of soybean seeds in July 2005, our station immediately established a soybean phytophthora root rot monitoring leading group and dispatched professional and technical personnel to carry out field monitoring work in Gongliu County. 1. Disease investigation In 2005, the affected area was 2239 hectares, and in 2006 the affected area was 2858 hectares. 1. Disease situation in Xinyuan County The soybean planting area was 0.67 million hectares, the investigated area was 0.3 million hectares, and the affected area was 0.23 million hectares, of which the sporadic occurrence area was 0.2
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