Guava Cultivation Technology and Pest Control: Prevention and Control of Diseases and Pests of Fruit Trees

3. The damage and occurrence of powder scale insects (1) The powder scale insects are common pests of fruit trees. Although their body size is small, they are no less harmful than large insects. In the past when bananas and citrus were exported, they were listed as Important quarantine pests. In recent years, due to the drought year by year, the entomopathogenic guava, Indian jujube, and cherimoya were all more serious than in previous years. The worm is characterized by an oval-shaped pale yellowish nymph, covered with white powdery secretions, commonly known as the white turtle, which occurs about 10 generations a year, and occurs during the dry season (November to May of the following year). About 26-55 days. After the mature female adults are mature, cotton-like white oocysts are secreted from the tail and spawned in the oocysts. The female adults each produce 234-507 eggs. Eggs are oblong, light yellow, smooth surface, egg period of about 2-8 days, in addition to male and female eggs in each period, can crawl on the leaves. Adults and larvae are often densely punctured and sucked on branches, leafhoppers and fruits. Excreta can cause coal disease and attract ants to feed on the plants, which can cause poor plant growth and affect quality. Ants have the behavior of protecting and spreading powder scale insects, and they have a mutual symbiotic relationship. Some farmers reported that the fruit was still damaged by powder scale insects after being bagged, causing the appearance of the fruit to be covered with a layer of coal disease, which seriously affected the quality. The reason may be that the farmer could not completely control the insects before fruit bagging, so that the powdered scale insects breed in the fruit after bagging, or they do not continue to control after bagging, and the powdered shell impregnates the bag and damages the fruit. (2) Prevention and cure method 1 Pay attention to plant pruning at ordinary times so that the plants are well ventilated and have good sunshine. 2 The fruit should be thoroughly controlled before the bagging, so as to avoid the scale insects breeding in the fruit, control difficulties. 3 Injury can be selected by 25%, cotton-preserved phosphate WP 800 times or 50% phobic emulsion 8000 times or 50% omethoate 1000 times, applied once every 10 days, 2-3 times in succession. When the medicine is sprayed, the leaves are evenly sprayed on the surface, but the spraying should be stopped 6 days before harvesting. When the near harvest period occurs, in order to consider the problem of remnants, it is recommended that 40% of the anti-phosphorus emulsion be sprayed 8,000 times, but the drug should be stopped 6 days before harvest. 4. Injury and Occurrence of Carp Follicles (1) Injury The guava horses have ventral hook horses, red belt thrips and flower thrips, of which the ventral hook horses are the most common and the most serious. The ventral hamster is the most severely damaged on the southern part of the mist. In recent years, it has increased its ability to adapt to crops. It poses a threat to guava, mango, carambola, cherimoya and grapes in fruit trees. The farmers call it chicken broilers. . Because of its adult worms on the sides of the fourth abdominal segment, it is called the name of the abdomen. The insects occurred in May. They mainly attacked the leaves, and they also gathered on the fruits. They sucked the juice from the skin and injured the skin, resulting in grey spots on the damaged parts. They turned to auburn, resulting in rough scars and reduced the appearance quality of the fruit. The growth in the field is different due to different climate and host species. In general, the density of the monthly population begins to rise from the $month to peak in August-September, and after 10-11 months, it is affected by low temperature and the density declines. Temperature and rainfall are related, especially the influence of temperature factor is more than the rain factor.(3) Prevention and control method The body is small, early occurrence is often overlooked, so there are three main points for prevention and control of the insect: 1 understand the ecology of the insect, predict the occurrence of the insect, Do a good job of field observation, and grasp the economic prevention and control.2 Familiar with the physiology of the worm, including the mouth licking device, the method of sucking and the position of the sucking horse.3 The choice of the right medicine, including the identification of the humming horse and the method of prevention and control. Choose 48.34% of the hydrogen bromide or 1500 times of butyl thiocarbamate (good winter), or 1000 times of the 50% Methionine WP, and apply it to the whole garden. In the afternoon, spray the medicine so as not to cause harm due to high temperature.5.Spiral aphid (1) Harmfulness and regularity This insect is a newly invasive pest in recent years. Its host is quite extensive, and fruit trees, flowers, and ornamental trees may be harmed and the host is harmed. There are 156 species in 65 families, and the host range will increase with the increase of adaptability. Adults spawn on young leaves, arranged in a spiral, and protected by white wax covering them, and the egg period is 10.3 days. After the nymphs inhabited on the back of the leaves, they only flew away from the activities until they became adults. The nymphal period is about 20.5 days. In addition to the direct nymphs sucking, the pests also secrete honeydew to induce coal diseases, affecting plant respiration and photosynthesis. The instar nymph secretes a white powdery and filamentous material from the body's back, and some of the powdery or false pods are scattered on the leaves and stick to honeydew to form a silver-black soot disease. ------(Unfinished)------- China Agriculture Network Editor

Vaccine Biotechnology

Vaccine Biotechnology,Vaccine Pre-Filled Syringe,Live Chickenpox Vaccine,Freeze-Dried Rabies Vaccine

Changchun Changsheng Life Sciences Ltd. , http://www.ccls-vaccine.com

Posted on