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Occurrence Characteristics and Control Methods of Pear Orchard Armored Scale
Pear orchard armored scale belongs to the order Homoptera, family Diaspididae, and is a pest that is relatively difficult to control on pear trees. In recent years, through observation, we have basically grasped the occurrence pattern of pear orchard armored scale in the Korla region, and through several years of control trials, we have developed a set of effective control methods. I. Damage Characteristics Pear orchard armored scale mainly damages fruit trees and forest trees. Among fruit trees, it mainly damages the branches, fruits and leaves of pear, apple, jujube, grape, apricot, plum, etc. Branches are often densely covered with many scale insects, and the damaged areas show red round spots; in severe cases, the cortex splits and even dies.
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Pest and Disease Control Methods and Technical Key Points for Bonsai
Diseases on branches and trunks: These manifest as rot of the phloem and cambium of branches and trunks, stem rot and cankers on branches and trunks, surface rot of branches and trunks, decay of the inner wood, and spots on twigs. In such cases, Bordeaux mixture should usually be sprayed, followed by lime sulfur mixture, and the decayed parts should be scraped off. Foliar diseases: Foliar diseases usually show symptoms such as yellow-brown or black spots, leaf curling, wilting, and early leaf drop, and may be chlorosis, leaf spot disease, sooty mold, powdery mildew, etc. For leaf spot disease, remove the diseased leaves and spray Bordeaux mixture; for chlorosis, use 0.1-0
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Pests Harming Orchids and Their Control Methods (Part One)
Pests that harm orchids include scale insects, aphids, spider mites, thrips, whiteflies, leaf miners, snails and slugs, nematodes, caterpillars, cockroaches, ants, and others. 1. Scale insects Scale insects are one of the most common pests harming orchids. There are many species, mainly parasitizing the stems and leaves of orchids, and they can also be seen on the petioles and the membranous sheaths at the base of pseudobulbs, appearing as a white powdery substance. They feed by sucking plant sap with their piercing-sucking mouthparts. In mild infestations, they cause the affected organs to turn yellow and age, affecting the growth of the orchid plant; in severe cases, they cover the leaf surface in patches, consuming nutrients and affecting the orchid's
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Causes and Control Methods of Magnolia Chlorosis
Also known as chlorosis, it is a common disease of magnolia, and occurs more commonly in areas with alkaline soil. In the northern regions of our country, the disease is relatively severe. Symptoms: The diseased plant first shows symptoms on the young tender leaves at the top of the shoots. The mesophyll tissue of the diseased leaves turns yellow or pale yellow, while the veins remain green; as the disease progresses, the entire leaf turns yellow to yellow-white, and the leaf margins become gray-brown or brown and necrotic. The condition gradually worsens, the plant grows weak, and eventually dies. Causes: Magnolia chlorosis is a non-
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Causes and Control Methods of Azalea Chlorosis
Azalea chlorosis is a non-infectious disease and also a common disease in azalea cultivation. After the plant is affected, the leaves become thinner, lose their green color, and turn pale, so this disease is also called chlorosis. The lack of green is obvious in new leaves. When the color of new shoot leaves becomes lighter and the leaf mesophyll turns yellow while the veins remain green, it is generally diagnosed as iron deficiency symptoms. This phenomenon mostly occurs in alkaline soil and in areas where slightly alkaline water is used to water flowers. After symptoms appear on the leaves, photosynthesis cannot proceed normally. In mild cases, it affects the growth and development of the plant
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What are the control methods for azalea leaf spot?
1. Symptoms: Small reddish-brown spots first appear on diseased leaves, gradually expanding into nearly circular spots, or restricted by leaf veins into polygonal lesions, 1-5 mm in diameter, dark brown; sometimes grayish-white in the center with indistinct edges. The spots are darker on the upper surface and lighter on the lower surface of the leaf, and lesions at the leaf margin may merge with one another; when humid, grayish-black mold spots mostly form on the surface of the diseased areas. 2. Pathogen: The pathogen of azalea leaf spot is Cercospora rhododendri Ferraris, belonging to the order Hyphomycetales, class Hyphomycetes. The grayish-black mold spots on the lesions are
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Identification and Control Methods of Rhododendron Flower Rot
Symptoms Rhododendron flower rot only harms the flowers, causing the flowering period to shorten, flowers to droop, and early withering and dropping. After the petals are infected, the diseased parts lose their luster, become water-soaked, soft and discolored, and finally turn brown, rot and blacken; when humid, a gray mold layer grows on the surface, affecting ornamental value. Pathogen and disease pattern This disease is caused by a fungus of the class Hyphomycetes, subphylum Deuteromycotina. The pathogen forms sclerotia on rotten flowers, and the sclerotia fall into the soil with the spent flowers to overwinter. In the flowering period of the following year, conidia are produced, spread by wind and rain or air currents, and when the flowers sprout
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Control Methods for the Azalea Spider Mite
Distribution and damage: it has occurred in Japan, South Korea, the United States and other countries. It damages azaleas, camellias, tea plants and others. Morphological features: female mite: reddish-brown, body length about 0.14 mm. Male mite: body length about 0.33 mm. This mite damages azaleas mostly from May to July and from October to December, when the damage is severe; it can suck sap on both the upper and lower surfaces of leaves, and in severe cases the leaves lose their green color and turn yellow-green.
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Occurrence and Control Methods of Brown Spot Disease in Rhododendrons
Brown spot disease is a common leaf spot disease of rhododendrons. It occurs fairly commonly throughout the country, and is especially severe in Guangzhou, Suzhou, Nanjing, Lianyungang, Wuhan, Hefei, Shenyang and other places. Besides harming rhododendrons, this disease also harms other plants of the genus Rhododendron. Symptom characteristics: Brown spot disease mainly occurs on the leaves. Initially, small reddish-brown spots appear on the leaf surface. They then gradually expand into nearly circular lesions, or polygonal lesions due to restriction by the leaf veins. The lesions are 2-5 mm in diameter and dark brown; in the later stage, the center of the lesion turns yellowish-white to grayish-white, with a dark brown edge (varying by variety).
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Identification and Control Methods for the Rhododendron Lace Bug
Also known as the pear lace bug and pear flower lace bug, it belongs to the order Hemiptera, family Tingidae. It is distributed throughout the country. The nymphs and adults damage potted ornamental plants such as rhododendrons, Chinese roses, camellias, banana shrubs, jasmine, wintersweet and Chinese wisteria. Damage symptoms: both adults and nymphs gather on the undersides of leaves to pierce and suck the sap, and the undersides of the damaged leaves show a black sticky substance that looks very much like splattered dirt. This feature makes it easy to distinguish from other sap-sucking pests. The entire underside of the damaged leaf turns rusty yellow, while the upper surface develops many pale spots; when the damage is severe, the spots merge into patches, so that the whole leaf loses its green color and looks pale from a distance.
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