-
Symptom Identification and Control Methods of Red Pine Bark Rot
Red pine bark rot, also known as weeping branch disease, soft branch disease, dead branch disease, and shoot blight, is a type of branch and trunk canker disease that mainly affects pine species. Symptoms: The disease affects the bark of branches and trunks of young red pine trees, and in severe cases can also occur at the base of the trunk, causing cankers. Pine needles above the infected area turn yellow-green to gray-green, and gradually turn brown to reddish-brown. The affected branches and trunks shrink and wrinkle due to water loss, and the needle drop scars appear slightly swollen. When the base of a lateral branch is infected, the lateral branch droops downward. When the base of a twig is infected, it
-
Symptoms and Control Methods of Red Pine Bark Rot and Resin Flow Disease
[Distribution and Damage] This disease occurs in red pine (Pinuskoraiensis) plantations throughout the three northeastern provinces. In the Yanbian area of Jilin Province, the cities (counties) of Yanji, Hunchun, Helong, Wangqing, Dunhua, Antu, Longjing and others have relatively severe incidence, with a general incidence rate of 20%-30%, severely affected stands at 50%-60%, and in individual stands at the Mao'ershan Forest Farm in Yanji City, the incidence rate reaches as high as 98.6%. The pathogen attacks the phloem and cambium of the trunk and lateral branches of young red pines, even penetrating deep into the surface xylem of the sapwood, causing the tissue to rot and die with a brown discoloration
-
Symptom Identification and Control Methods of Red Pine Needle Cast
Red pine needle cast is a common disease worldwide. The disease can infect trees from young saplings to large trees, causing premature needle drop, affecting growth, and can lead to the decline and death of diseased plants. Symptoms: The disease usually affects 2-year-old needles, and some 1-year-old needles can also be affected. In the early stage of the disease, very small yellow spots or segmental spots appear on infected needles, and by late autumn the entire needle turns yellow and falls off. In the spring of the following year, larger, black or gray, long oval or oval raised granular dots appear on infected needles, with a paint-like luster and a longitudinal crack in the center, which are the ascocarps of the pathogen. Some diseased needles
-
Symptoms and Control Methods of Korean Pine Blister Rust
Symptoms: The disease occurs on the bark of branches and trunks. In the early stage of infection, the affected bark swells slightly and softens, cracks begin to form in early May, and yellowish-white blister sacs, which are the rust pustules (aecia) of the pathogen, emerge from within. In early to mid-June, the rust pustules mature and turn orange-yellow. From mid-May onward, the sacs rupture and release powdery rust spores, finally leaving a membranous white covering that gradually falls away and disappears. By the end of June, most blister sacs have ruptured and dispersed; the old diseased bark becomes rough and often develops a layer of sooty mold fungi, appearing black. Because the disease occurs year after year, the bark thickens and swells, and resin flows out. In late August and September
-
What are the control methods for red spider mites on rhododendrons?
The female adult is about 0.3 mm long, dark red, nearly oval, with a raised back and 4 pairs of dark red legs; the male adult is 0.25 mm long, wedge-shaped, flat and bright red. It produces multiple generations a year, and the adults overwinter at the base of the plant. They mainly cause damage on the underside of leaves near the midrib close to the petiole. During the high-temperature, low-rainfall, dry weather of June to July, they reproduce quickly, and when their numbers are high, the damaged leaves scorch and drop off. Control methods: manual control - check frequently after April, and if red spider
-
What are the control methods for anthracnose in Spanish dagger (Yucca gloriosa)?
Anthracnose in Spanish dagger (Yucca gloriosa) is a common disease of the plant, and it spreads very quickly. If it is not controlled in time after onset, it will not only affect the ornamental effect, but in severe cases it will also cause the plant to die. Its symptoms, development pattern and control methods are described below: Symptoms: It first appears at the leaf tip, initially as brown spots, which then expand outward in a circular or irregular shape. The inside of the lesion is grayish brown, surrounded by a yellow halo, with scattered black granular bodies on the surface. After the entire leaf is infected, it turns black. Development pattern: This disease is caused by
-
The Harm and Prevention and Control Methods of Orchid Virus Diseases
Viruses are relatively primitive organisms. They have no cellular structure and can only replicate by parasitizing host cells. Once infected, there is generally no specific drug for treatment, so viral diseases can only be prevented. Prevention can be achieved by improving environmental sanitation and raising cultivation techniques. More than 20 kinds of viruses that can infect orchids have been discovered so far. The more common ones include Cymbidium mosaic virus (CyMV), Cucumber mosaic virus (CMV), Dendrobium mosaic virus (DeMV), Cymbidium ringspot virus (CyRV), and others.
-
Symptoms Identification and Control Methods of Phalaenopsis Sunken Spot Disease
Main symptoms: When this disease first occurs, spots appear on the leaf surface
-
Common Disease Prevention and Control Methods and Technical Key Points for Silkworms
I. Pebrine. Commonly known as flower intestine, it is a devastating infectious disease. 1. Cause: Infection by the spores of Nosema bombycis. Transmission routes: first, transovarial transmission, that is, infected eggs laid by diseased female moths pass the infection to offspring; second, oral infection, that is, silkworms contract the disease after eating spores of Nosema bombycis. 2. Symptoms: Uneven colony development, thin and small silkworm bodies, poor appetite, many become non-molting silkworms, rise late or molt poorly, and sometimes there are dark brown spots of varying sizes like pepper powder on both sides of the ventral surface. Tearing open the outer skin of diseased 5th-instar silkworms reveals
-
Control methods and key technical points for the peach fruit moth
(1) Manual and physical control. Scraping bark to destroy pupae: during the dormant season of winter jujube, manually scrape off the coarse bark and scaly bark on the trunk and branch forks; beforehand, spread plastic sheeting under the tree to collect the bark and cocoons, then pour boiling water over them in a centralized manner. Blacklight trapping of adults: during the adult emergence period, set up blacklight lamps (insect-killing lamps) to trap and kill adults. From May to June, remove the moth cocoons missed by chemical control. From early September, tie grass bundles at the trunk and branch forks to attract the insects for pupation, then take them down and burn them. (2) Chemical control. The key is
条件筛选