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Symptoms and Control Methods of Smut Disease in the Medicinal Plant Sagittaria
Sagittaria, scientific name Sagittaria trifolia L., commonly known as arrowhead, belongs to the family Alismataceae. The whole plant and corms are used as medicine. It has the effects of clearing heat and stopping bleeding, detoxifying and reducing swelling, and dissipating nodules. It is also a vegetable for autumn and winter. It is mostly planted in rice fields after the rice harvest. It is distributed in all provinces and regions of northern and southern China. Symptoms mainly damage leaves, petioles, flowers and corms. On the leaves, yellow to orange-yellow, slightly raised blister spots of varying sizes first appear, and later the blister spots wither and yellow and rupture, releasing small black powder particles, which are the spore masses of the pathogen. Some diseased leaves are deformed and twisted. Leaf
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What are the control methods for the privet geometrid?
Distribution: distributed in Northeast China, Henan, Jiangsu, Zhejiang; also in Korea, Japan, and the Soviet Union. Damage: it harms water fir, privet, lilac, water wax, and small wax. The larvae spin silk webs and feed inside them. When the population is high, they form large silk webs that cover the entire tree, eating all the leaves, affecting tree growth and even causing the trees to die. Morphological characteristics: [Adult] body length 12-15 mm, wingspan 31-40 mm, body and wings white with a silky luster. The outer margin of the wings has 2 pairs of black dots, the outer row between the veins and the inner row on the veins; the forewing has at the upper end of the discal cell
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Identification Features and Control Methods of the Privet Looper
Scientific name: Naxa seriaria Motschulsky. Morphological features: The adult has a wingspan of about 40 mm, with a slender body that is yellow-white. The forewings and hindwings are thin, white, and slightly transparent, with two rows of black star-shaped spots along the outer margin, and each wing has a relatively large black spot in the middle. The forewing also has a row of dark brown spots near the basal angle. Newly laid eggs are white, gradually turning orange-red, glossy, and arranged in bead-like strings. The larva is about 30 mm long, dark brown, with indistinct black patterns and spots on its body. Except for the thoracic legs and the prolegs on the eighth and ninth abdominal segments, the prolegs on the other segments are all reduced, and each segment is covered with gray-white hairs. The pupa is yellow-brown with dark brown spots and patterns. Damage situation: This insect mainly damages privet (Ligustrum), water wax (Ligustrum obtusifolium), and osmanthus (Osmanthus fragrans). It is a voracious leaf-eating pest that often gathers in groups and nibbles away the leaves. Especially when the population density is high, it can completely devour the leaves of an entire plant or a whole patch of water wax and privet in a short period, seriously affecting growth and ornamental value. Occurrence pattern: This insect has two generations per year and overwinters as middle-instar larvae on the tree canopy. Pupation begins in mid-May, and adults emerge at the end of May and in early June. Adults mate on silk webs and lay eggs in strings. After the eggs hatch, the larvae spin silk webs on the tree canopy and nibble the leaves until they are eaten up, then spread to neighboring canopies. The second-generation adults appear around August, and the adults are phototactic. Control methods: 1. During the peak emergence period of adults, use lights to trap and kill the adults. 2. The pupae and eggs are all attached to the insect silk webs near the tree canopy, so they can be searched for and removed. 3. In the early stage of larval hatching, spray 1-2 times with insecticides such as dichlorvos, trichlorfon, and omethoate at a 1000-fold dilution. This insect has strong resistance to pesticides, so spraying should be thorough and should be done early; otherwise, the efficacy will be affected.
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What are the control methods for scale insects on privet hedges?
In recent years, with the widespread use of golden privet (Ligustrum sinense 'Variegatum') and small-leaf privet (Ligustrum quihoui) in urban landscaping, pests and diseases on privet have become a major problem in garden maintenance and management. The scale insect occurring on Ligustrum landscaping plants is mainly the white wax scale (Ericerus pela). It has been reported that comstock mealybug (Pseudococcus comstocki) has occurred on privet hedges in Hebei. The identification characteristics and control measures of the white wax scale are described below: Distribution and damage. The white wax scale Ericerus pela (Chavannes) belongs to the order Homoptera, family Coccidae. It is widely distributed in China. It damages
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What are the control methods for the Ligustrum looper moth?
The adult Ligustrum looper moth has wing patterns that slightly resemble the woven texture of a basket, with distinctive features, and a wingspan of about 9-10cm, making it a large moth. The larvae are grayish-black, or brightly colored in lighter shades; when young, the 2nd and 3rd body segments each bear two dorsal horns, and when nearly mature, the 2nd and 3rd segments swell and the area around the spiracles is vividly colored. When disturbed, the larvae can produce a cackling sound from their mouths. Adults emerge in June-July. Host plants include Ligustrum lucidum (glossy privet), Ligustrum sinense (Chinese privet), Ligustrum japonicum (Japanese privet), Fraxinus chinensis (Chinese ash), Osmanthus fragrans (sweet osmanthus), and others. Currently it is the period when older larvae are causing damage, and it is commonly seen in our area. Control methods:
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Symptoms and Control Methods of Privet Leaf Rust
Privet, also known as wintergreen and wax insect tree, is an evergreen small tree native to China and Japan. It likes light and tolerates slight shade, prefers warm and humid conditions, is suitable for slightly alkaline soil, is slightly cold-resistant, and has strong resistance to air pollution. Privet is a commonly used landscaping tree in courtyards and can be used as hedges and courtyard landscaping trees. Symptoms: Round brown spots appear on the surface of infected leaves and gradually become sunken, while the corresponding parts on the back of the leaves bulge. The mesophyll of the diseased area thickens and turns yellow or purplish red, after which many cup-shaped rust spore receptacles grow on the raised spots. Rust spores
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What to Do About Root Rot in Golden Privet? A Detailed Guide to Effective Prevention and Control Methods
To prevent root rot, pay attention to the following points: 1. Do a good job of disinfecting the seedbed. Avoid using land that has previously been sown or used for cuttings of similar seedlings as a seedbed. 2. Do a good job of disinfecting the cuttings. After cuttings are inserted, the entire seedbed should be disinfected; generally, the branches can be soaked directly in thiophanate or carbendazim solution, which gives a clear disinfection effect. 3. Pay attention to rooting time. Golden privet is a plant of the Oleaceae family that roots very easily; its cutting method can follow that used for golden-leaf privet, with attention to management and timely spraying of medicine to prevent disease. 4. Open
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Control Methods for the Ligustrum Looper Moth Damaging Ornamental Garden Trees
Distribution and Damage The ligustrum looper moth Naxa seriaria Motschulsky, also known as the lilac looper moth, belongs to the order Lepidoptera, family Geometridae. It is distributed throughout Northeast, North, Northwest, Southwest and East China. The larvae damage Syringa reticulata, Syringa pekinensis, Syringa reflexa, Syringa oblata, Syringa wolfii, Syringa oblata var. alba, ligustrum, large-leaved ligustrum, osmanthus, camellia, tea, privet, Manchurian ash and Chinese ash, etc. The larvae gather in groups to feed on leaves and often strip the leaves completely. The larvae have the habit of spinning silk to form webs; in severe cases the webs cover the tree crown,
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Causes and Control Methods of Leaf Yellowing in Winter Red Fruit Bonsai
Winter red fruit flowers easily and has a high fruit-setting rate. Its fruits are entirely red, and the fruiting period can extend to the next year's flowering and leafing stage without dropping. It is an excellent variety for fruit-viewing bonsai and is deeply loved by the people. However, during cultivation, due to the limitation of pot capacity and other influences, the leaves often turn yellow and drop. The main causes of yellowing are as follows: Temperature. Winter red fruit prefers warm and humid conditions and likes light but not excessively strong light. Especially in hot summers, strong direct sunlight will make the air dry and raise the pot soil temperature.
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What are the control methods for southern blight in orchids?
Southern blight is caused by the fungus Selerotiumrolfsii, which harms the stem base and roots from seedlings to mature plants, and Cymbidium hybridum is more susceptible to this disease. When the disease occurs, white mycelium can be seen at the stem base, the stem base turns brown, the roots dry up, and a large number of small brown sclerotia form, causing the plant's stem base to soften and die. This pathogen has a very wide host range and causes more serious damage to bulbous flowers and perennial flowers. It also has strong saprophytic ability and can survive for a long time in the substrate or old pots through sclerotia. This fungus can also infect Phalaenopsis
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