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How to control cotton aphids in summer? These methods you need to master
Control of cotton aphids in summer. 1. Rotate the use of pesticides. Rotate the use of conventional field pesticides such as acetamiprid, imidacloprid and chlorpyrifos to reduce the likelihood of aphids developing resistance. Once aphids develop resistance to a certain chemical pesticide, even if you increase the number of applications and raise the pesticide concentration, you will not achieve the desired control effect. 2. Spray the affected parts evenly and thoroughly. Cotton is now in full bloom and the plants are tall, so when spraying you must be careful and thorough, focusing on spraying the undersides of the leaves in the middle and lower parts of the cotton plant, strictly preventing missed spraying and missed coverage, and truly
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Control Methods and Technical Key Points for Cotton "Double Rot" Disease
Rotten bolls and rotten peaches are common, frequently occurring diseases of cotton that seriously affect cotton yield and quality. People customarily call these two diseases "double rot disease." (1) Causes 1. Excessive or too-late application of nitrogen fertilizer causes excessive cotton growth and a closed, shaded field, which weakens the disease resistance of cotton plants. 2. During the flowering and boll stage, cotton encounters heavy rainstorms or excessive autumn rain, field humidity is too high, and drainage is poor, causing pathogens to breed and invade. 3. Cotton is attacked by red rot, anthracnose, boll blight, and other diseases. (2
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Symptom identification and control methods of cotton white mildew
Symptoms The disease occurs in the middle and late growth stages of cotton in all cotton regions. At first, white spots 3-4 mm in diameter appear between individual leaf vein networks, then become irregular polygons. On the upper surface of the leaf, the lesions are light green to yellow-green, and on the corresponding lower surface, many white frost-like conidiophores and conidia are produced. In severe cases, the diseased leaves dry up and fall off. The pathogen Ramularia areola Atk. is called white-spot Ramularia or cotton Ramularia, a fungus of the Deuteromycotina. The conidiophores are colorless, emerge in bundles from the stomata on the lower leaf surface, mostly branch at the base, and have tooth-like
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Occurrence Patterns and Control Methods of Cotton Pests under Drip Irrigation
With the large-scale application of drip irrigation technology for cotton, the irrigation method has been improved. It delivers water and nutrients evenly and continuously to the vicinity of the cotton root system at scheduled times and specific locations, and the supporting cotton cultivation techniques have changed accordingly, causing corresponding changes in the ecological environment of cotton field pests and their occurrence patterns. For this reason, it is highly necessary to clearly understand the occurrence patterns of cotton pests and the technical control measures under mulched drip irrigation, so as to ensure sustained and balanced increases in cotton yield. 1. Cotton bollworm 1. Occurrence level Compared with previous years, the occurrence in 2005 was moderate to severe
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What are the control methods for the tea white scale (Pseudaulacaspis pentagona)?
The tea white scale belongs to the order Homoptera, family Diaspididae. It is distributed in most tea-producing provinces across the country and is an important tea tree pest in East China and Southwest China. Besides damaging tea, it also harms various plants such as citrus, pear, and apple. It damages tea trees by nymphs and female adults parasitizing on branches and trunks and sucking sap. Affected tea trees sprout sparsely, decline in vigor, age prematurely, and in severe cases shed a large number of leaves or even die. Morphological characteristics: the female's scale cover is grayish-white, about 1.5 mm long, narrow and slightly curved like a bent eggplant, slightly wider at the rear end and with a brown scale point at the front end.
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Identification and control methods of the tea shot-hole borer
The adult and larval stages of the tea shot-hole borer both bore into the branches and trunks of lychee and longan, with branches 1-2 cm in diameter being the most heavily affected, and numerous nearly circular small entrance holes visible on the exterior. If an affected branch is cut open, several nearly ring-shaped horizontal small galleries will be found in the xylem, and dark brown beetles smaller than a grain of rice, or milky white legless larvae and pupae, are commonly seen. Because the transport of water and nutrients in the affected branches is blocked, the trees weaken in vigor and often produce dead branches and broken branches, and entire young trees have even been found killed by the damage. In recent years the tea shot-hole borer
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Occurrence and Damage Characteristics of Tea Tussock Moth and Integrated Control Methods
In recent years, with the development of pollution-free tea and organic tea production, the frequency and amount of chemical pesticides used in tea gardens have decreased, and some tea gardens even do not use chemical pesticides, resulting in aggravated damage by the tea tussock moth in a short period. In the county where the author works, tea tussock moth damage has occurred for several consecutive years, and after being damaged, the tea plants were left with only bare branches, greatly affecting the economic income of tea farmers. 1. Damage symptoms: The tea tussock moth larvae bite and feed on leaves, causing leaf notches and bare branches. 1st-2nd instar larvae gather on the underside of leaves to feed on the mesophyll, leaving only the epidermis and veins, and the damaged leaves appear transparent
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Identification and Control Methods for the Tea Bug and the Yellow-Spotted Bug
Distribution area: Morphological characteristics: The adult tea bug (Halys dentata) is about 15 mm long and 8-9 mm wide. The body is flattened and oval. Grayish-brown, with a slight purplish-red tinge. The antennae have 5 segments; segment 2 is longer than segment 3; both ends of segment 4 and the base of segment 5 are yellow. The thorax dorsum and forewings are densely covered with dark brown punctures. The eggs are cup-shaped and grayish-white. 20-30 eggs are arranged into an egg mass. The nymph is slightly flattened and round, dark brown, with dark spots on its back. The adult yellow-spotted bug (Erthesina fullo) is 20-30 mm long and 8-11 mm wide. Grayish-brown, with the body dorsum and forewings densely
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What are the control methods for tea plant purple root rot?
Distribution and symptoms: It is found in all tea-producing areas, but occurs fairly commonly in North China and East China. This disease mainly occurs at the seedling stage and the mature plant stage, damaging the roots or the root collar. First the fibrous roots rot, turning brown or dark brown, then it spreads to the lateral roots, which after rotting turn purplish brown. The surface of the lesions is covered with purplish brown thread-like matter, and on the surface of the diseased roots there are hemispherical granular sclerotia. The base of the small stem plus cm is often surrounded by purplish red mycelium, soft in texture; it peels off easily, and the root cortex also peels off easily. In severe cases the aboveground part wilts, new shoot sprouting decreases, and the diseased plant dies. Occurrence pattern
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What to Do About Golden Privet Leaf Drop During the Growing Season? Causes and Control Methods
Causes and Control Measures for Leaf Drop of Golden Privet During the Growing Season Caused by Disease According to expert research, this leaf spot disease is caused by the pathogenic fungus Alternaria (afternaria) of the order Moniliales, class Hyphomycetes, subdivision Deuteromycotina. In the early stage, small brown spots appear on the leaves, surrounded by purplish-red halos, and black mold-like growth is visible on the spots.
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