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Occurrence and Control Methods of Oleander Aphid Infestation
Morphological characteristics: The aphid belongs to the order Homoptera, family Aphididae. Wingless parthenogenetic female: body length 2.3 mm, width 1.2 mm, oval in shape, yellow in color, with distinct markings on the eighth abdominal segment. The body surface has obvious reticulate patterns. The median frontal tubercle is raised, with a flat top; the antennae have imbricate sculpturing and are 2/3 of the body length. The cornicles are long and tubular; the cauda is tongue-shaped, constricted in the middle, bearing 11-14 long curved hairs. Winged parthenogenetic female: body length 2.1 mm, width 1.0 mm, elongate-oval; head and thorax black; antennae 3/4 of the body length. Abdominal segments 2-4 have small marginal tubercles; cornicles are long and cylindrical.
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How to prevent and control pests and diseases of oleander? A detailed guide to practical methods
1. After aphids are found, spray the plants with a 40% dichlorvos emulsion at 800 times dilution, or with water in which cigarette butts have been soaked; when there are only a few, they can also be brushed off. For other control methods, refer to the pest and disease control section for Chinese rose and scarlet sage. 2. Scale insects damage the branches and leaves. Control method: spray the plants with Jiesha at 2000 times dilution. For other control methods, refer to pest and disease control for crape myrtle. 3. Black spot disease This disease occurs easily under high temperature and high humidity and damages the leaves. After it appears, spray with 50% carbendazim at 500 times dilution or thiophanate-methyl at 600 times dilution. For other control methods
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Comprehensive Control Methods for Damping-Off Disease in Spruce Seedlings Grown in Greenhouse Tunnels
In high-cold mountain areas, greenhouse tunnel seedling cultivation is usually adopted to shorten the cultivation period of spruce seedlings and enable earlier out-planting. The special environment of the greenhouse tunnel creates conditions for the breeding and spread of various pathogenic bacteria and organisms that cause damping-off in newly sown spruce seedlings, and improper control can lead to failure of seedling cultivation. To control damping-off in newly sown spruce seedlings in greenhouse tunnels, the policy of "prevention first, comprehensive control" must be adhered to. 1 Damping-off symptoms The symptoms of damping-off mainly manifest in 4 types: (1) After sowing but before emergence, seeds and ungerminated sprouts rot and die in the soil,
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Symptom Identification and Control Methods for Black Locust Trunk Rot
Symptoms: The disease affects the branches and trunks of young trees to large trees, causing branch dieback or death of the entire tree. In large trees, it mainly occurs at the base of the trunk, and in a few cases at the forks of upper branches and tips. When the base of a large tree is affected, there are no obvious external symptoms; when the bark is peeled back, the interior has already discolored and rotted, with a foul odor, and irregular brown to dark brown patches appear on the surface of the xylem. The lesions continuously expand, encircling the trunk for 1 full turn, causing the branches and trunk above the lesion to die, and the leaves immediately turn yellow and wilt. When the branch tips or the main stem of young trees are affected, the diseased tissue shows water-soaked rot, producing obvious canker lesions that are slightly sunken with purplish-brown edges
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What are the control methods for spruce red blight?
In recent years, with the increase in the number of spruce plantings, spruce red blight has become severe, reaching up to 50% in some dense forest belts, seriously weakening tree vigor and even causing tree death. The disease develops rapidly, spreading from the lower part of the tree to the upper part, from the outer edge of the crown inward, and from the base of the compound leaves to the tip. In as many as 10 days, or as few as 1 week, the entire tree's leaves can turn yellow and then fall off. The disease is caused by fungi. When temperature changes abruptly and humidity increases, the tree shows symptoms. Diseased leaves first develop small brown spots, which later expand and turn dark brown; when wet from rain, the lesions produce
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Control Methods for Spruce-Bird Cherry Cone Rust
Spruce-bird cherry cone rust occurs in Inner Mongolia, Jilin, Heilongjiang, Sichuan, Yunnan, Tibet, Shaanxi, Gansu, Qinghai, ** and other places in China. The disease damages Picea asperata (dragon spruce), Picea purpurea (purple cone spruce), Picea likiangensis (Likiang spruce), Picea brachytyla var. complanata (oil wheat hanging spruce), Picea jezoensis (Yeddo spruce), Picea schrenkiana (Schrenk spruce), ** spruce and others. Symptoms: The disease damages the upper surface of female cone scales. Infected scales are twisted, rolled back and disorganized. On the upper surface, many purplish-brown small spheres are produced, arranged in a single layer; these are the aeciospore pustules of the pathogen. Sometimes aeciospore pustules also form on the underside of the scales.
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Control Methods for Several Diseases of Phalaenopsis
Anthracnose is severe under high temperature and high humidity, forming brown-black round spots that gradually expand outward. Spray evenly with Previcur 800 times solution, once every 5 days, for 2 to 3 consecutive sprays, to bring the disease under control. Soft rot symptoms are rot at the leaf base, rot of the pseudobulb, with a musty bacterial odor. Control method: spray agricultural streptomycin sulfate 4000 to 5000 times solution at the early stage of disease, once every 7 days, for a total of 2 to 3 sprays. Sclerotinia disease symptoms first appear at the leaf base, with light brown, water-soaked lesions that rot and can spread to the whole
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Occurrence Patterns and Control Methods of Jujube Witches' Broom
Jujube witches' broom is a devastating disease that should be prevented rather than cured. It is very prevalent in jujube-producing regions of China. Once a tree is infected, it rarely bears fruit the following year, and even if it does, the fruit loses its edible value; after 3~4 years the entire tree dies. I. Causes of jujube witches' broom: The main cause of jujube witches' broom is the invasion of mycoplasma-like organisms. Mycoplasma-like organisms can be spread through grafting. Under natural conditions, natural root grafting between trees can also spread the disease, and some leafhoppers are also carriers of mycoplasma-like organisms. II. Integrated control measures: 1. Select and breed disease-resistant
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Identification and Control Methods for the Peach Fruit Moth
Latin scientific name: Carposina niponensis Walsingham Distribution: Morphological characteristics: Adult body length 7-8 mm, wingspan 16-18 mm, grayish brown. The middle of the front wing's leading edge has a large blue-gray nearly triangular patch. The wing surface has 7 clusters of blue-brown obliquely erect scale hair tufts. The female's labial palps are longer, the male's shorter. Eggs are oval, red, with 2 or 3 rings of "corpse-shaped bristles" at the top. Larvae are 13-16 mm long, peach-red, with a brown pronotal plate. Young larvae are yellowish-white. No anal
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What are the control methods for bacterial shot hole disease in peach trees?
(1) Damage symptoms. Peach bacterial shot hole disease mainly damages peach leaves, and also infects twigs and fruit. After leaves are affected, nearly round or irregular brown lesions appear, and the lesions gradually dry up and fall off to form shot holes, hence the name shot hole disease. In severe cases, several lesions often join together to form large scorched patches, causing most of the leaf to dry up and resulting in early defoliation, so the disease is also called peach early defoliation disease. (2) Control methods. 1. Strengthen comprehensive management of the peach orchard. Apply more organic fertilizer, avoid
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