What are the methods for controlling pests and diseases of golden privet?
Along the roadsides of most cities, we can often see golden privet (detailed introduction), which is mainly used for urban greening. The leaves of golden privet are golden yellow, and the various patterns they form with other plants are of great significance to the ecological construction of our cities.
Golden privet (detailed introduction)
Although golden privet brings much beauty to our cities, it often suffers from certain diseases, which not only fail to beautify our cities but instead cause a certain amount of pollution. The control of pests and diseases of golden privet was once a rather troublesome matter for the relevant personnel. However, with the development of industry, we have found many methods to prevent these diseases. Even so, the control of pests and diseases of golden privet still requires the attention of the relevant workers. So what are the methods for controlling pests and diseases of golden privet?
In fact, the control of pests and diseases of golden privet mainly includes three major categories: protecting and utilizing natural enemies, using insect adhesive glue to trap and kill, and chemical and biological control. Using insect adhesive glue to trap and kill means fixing the insect adhesive glue onto the branches and trunks of golden privet, so that flying pests get stuck on the glue, unable to move normally, and die. Although chemical and biological pest control methods using insecticides have the effect of quickly killing pests, they will damage the environment to a certain extent. Among these three major categories of pest and disease control methods, the method of protecting and utilizing natural enemies is relatively environmentally friendly, but it is somewhat difficult to carry out.
Methods for controlling pests and diseases of golden privet
Golden privet is an evergreen small shrub with very strong adaptability and low requirements for the growing environment, but even so, some pests and diseases still occur. Today, the editor shares with you the methods for controlling pests and diseases of golden privet.
Golden privet pest: mealybugs
Adult and nymph mealybugs pierce and suck plant sap. In severe cases, the branches and trunks are covered with the insects, causing weak growth and susceptibility to sooty mold and other diseases. It is a pest that is difficult to control and causes serious damage.
Mealybugs occur in three generations a year, overwintering as egg sacs in the coarse bark cracks of branches, outside cracked bark, in soil and stone crevices near the plants, or in fallen leaves. When the female adult lays eggs, it first forms a cotton-like waxy egg sac, then lays eggs inside the sac. The first-generation nymphs begin to hatch in large numbers from mid to late May, and this generation hatches relatively uniformly. The second-generation nymphs hatch in large numbers from mid to late July, and the third-generation nymphs hatch in large numbers from late August, with the latter two generations hatching less uniformly. According to observation, Hengshui City is more severely affected by mealybugs from June to September.
Control methods for the golden privet pest mealybugs:
(1) Thoroughly clear and burn fallen leaves in winter and spring, which can greatly reduce the insect population; use a stiff brush to brush away the egg sacs in coarse bark cracks and cracked bark.
(2) During the growth period of the first-generation pests, spray them twice with an interval of about 10 days, with remarkable results. Spraying should also be carried out during the damage period of nymphs of each generation. It is recommended to use scale-insect-specific products, dilute the product 1000-1500 times and spray evenly. Use continuously 2-3 times with an interval of 7-10 days, with remarkable results.
Golden privet leaf spot disease
Leaf spot disease has been the most serious disease affecting golden privet in Hengshui City in recent years. When it breaks out, it even causes the leaves of entire patches of plants to fall off. This not only affects the growth of the plants but also makes them lose their ornamental value.
Leaf spot disease is a fungal disease. It overwinters in the form of mycelium on diseased plant residues. Conidia spread through airflow or contact between branches and leaves, and invade the host through wounds and stomata. The optimum temperature for pathogen growth is 26°C, and the optimum temperature for spore germination is 18°C to 27°C. In the early stage of the disease, nearly round brown spots appear on the leaves, often with concentric rings, and the outer edge is yellow. In the early stage, the spots are relatively small, then expand into irregular reddish-brown large spots with a grayish-white center and scattered small black dots, and later the spots merge into patches. Diseased leaves fall off the branches very easily, thus causing the affected areas of golden privet to appear bare of branches and stems.
Control methods for golden privet leaf spot disease:
(1) The planting density should be appropriate and not too dense; clear and centrally burn dead branches and fallen leaves in late winter and early spring; prune appropriately, especially heavy pruning before sprouting in spring, which can effectively reduce branch density. Appropriate pruning during the growing season can effectively improve ventilation and light transmission conditions and reduce conditions favorable to disease occurrence.
(2) Appropriately reduce the application of nitrogen fertilizer and increase the application of phosphorus and potassium fertilizers to enhance plant resistance.
(3) Before the disease occurs in mid-June, spray Junmie products, dilute the product 400-600 times, and spray evenly.
The above is the article on methods for controlling pests and diseases of golden privet. We hope it can help you. Do not assume that golden privet will not get sick just because its growth ability is particularly strong. We still need to pay attention to the prevention and control of pests and diseases of golden privet.
Control of pests and diseases of golden privet
Control of pests and diseases of golden privet -- The advantages of golden privet, such as easy cultivation, rapid growth, and tolerance to pruning and shaping, make it widely used in landscaping projects in northern regions. Hengshui City, Hebei Province, has a history of more than ten years of planting golden privet. With the increase in application area and time, its pests and diseases have also become increasingly serious. Based on years of observation and research, the author summarizes the occurrence patterns and control techniques of several of the most common and seriously damaging pests and diseases.White grubs
Observation has found that golden privet is a high-quality food source for white grubs. In areas planted with red-leaf barberry, large-leaf boxwood, Henan juniper, and dragon juniper, only golden privet is obviously harmed by white grubs. In seriously affected areas, they even often cause entire patches of plants to die.
White grubs are the larvae of scarab beetles. They bite and feed on the roots of golden privet. The aboveground parts of the bitten plants initially show symptoms of water-deficiency wilting. If the damaged plants have sufficient water and the ground remains moist, they will not die, but their growth will be weak. In addition, the root epidermis below the ground of the damaged plants is gnawed away, making them easy to pull out. Plants with sufficient water can only grow a small number of new roots close to the soil surface.
The physiological characteristics of white grubs are one generation per year, overwintering in the soil as adults or larvae. In northern regions, from April to the end of May each year is the period when overwintering larvae emerge, pupate, and lay eggs. From May to July is the emergence and egg-laying period of the first-generation larvae. From September to November is the period of vigorous activity of overwintering larvae.
Control methods:
(1) When planting seedlings, use compost and barnyard manure as base fertilizer, and apply them only after they are fully decomposed. (2) When the area damaged by white grubs is relatively small, pull out the damaged seedlings and dig out the larvae near the roots of the seedlings, and the digging range should be appropriately enlarged. (3) Take advantage of the adults' death-feigning behavior to catch or shake them off the crops where they rest and kill them. Or take advantage of their phototaxis and use black light lamps to trap and kill adults. (4) When adults feed and cause damage, spray 4.5% beta-cypermethrin 1000 to 1500 times dilution, 50% phoxim emulsifiable concentrate 1000 times dilution, or 15% chlorpyrifos 1000 times dilution and other insecticides to kill adults; during the larval damage period, pour 1000 to 1500 times dilution of 50% phoxim emulsifiable concentrate, or 900 to 1000 times dilution of 90% trichlorfon solution onto the roots of the seedlings. The author's practice is to pour phoxim once in early June on the area damaged the previous year, and pour it again in early July. Through these two pourings, the pests are completely eliminated.
Mealybugs
Adult and nymph mealybugs pierce and suck plant sap. In severe cases, the branches and trunks are covered with the insects, causing weak growth and susceptibility to sooty mold and other diseases. It is a pest that is difficult to control and causes serious damage.
Mealybugs occur in three generations a year, overwintering as egg sacs in the coarse bark cracks of branches, outside cracked bark, in soil and stone crevices near the plants, or in fallen leaves. When the female adult lays eggs, it first forms a cotton-like waxy egg sac, then lays eggs inside the sac. The first-generation nymphs begin to hatch in large numbers from mid to late May, and this generation hatches relatively uniformly. The second-generation nymphs hatch in large numbers from mid to late July, and the third-generation nymphs hatch in large numbers from late August, with the latter two generations hatching less uniformly. According to observation, Hengshui City is more severely affected by mealybugs from June to September.
Control methods:
(1) Thoroughly clear and burn fallen leaves in winter and spring, which can greatly reduce the insect population; use a stiff brush to brush away the egg sacs in coarse bark cracks and cracked bark. (2) During the growth period of the first-generation pests, spray them twice with an interval of about 10 days, with remarkable results. Spraying should also be carried out during the damage period of nymphs of each generation. The insecticides used include Dujie, Lesiben, Jiesijing, and others. Spray evenly, and add 0.1% neutral laundry powder when spraying to increase efficacy.
Leaf spot disease
Leaf spot disease has been the most serious disease affecting golden privet in Hengshui City in recent years. When it breaks out, it even causes the leaves of entire patches of plants to fall off. This not only affects the growth of the plants but also makes them lose their ornamental value.
Leaf spot disease is a fungal disease. It overwinters in the form of mycelium on diseased plant residues. Conidia spread through airflow or contact between branches and leaves, and invade the host through wounds and stomata. The optimum temperature for pathogen growth is 26°C, and the optimum temperature for spore germination is 18°C to 27°C. In the early stage of the disease, nearly round brown spots appear on the leaves, often with concentric rings, and the outer edge is yellow. In the early stage, the spots are relatively small, then expand into irregular reddish-brown large spots with a grayish-white center and scattered small black dots, and later the spots merge into patches. Diseased leaves fall off the branches very easily, thus causing the affected areas of golden privet to appear bare of branches and stems.
Control methods:
(1) The planting density should be appropriate and not too dense; clear and centrally burn dead branches and fallen leaves in late winter and early spring; prune appropriately, especially heavy pruning before sprouting in spring, which can effectively reduce branch density. Appropriate pruning during the growing season can effectively improve ventilation and light transmission conditions and reduce conditions favorable to disease occurrence. (2) Appropriately reduce the application of nitrogen fertilizer and increase the application of phosphorus and potassium fertilizers to enhance plant resistance. (3) Before the disease occurs in mid-June, spray protective fungicides such as mancozeb. After the disease occurs, spray once every 10 days with 50% carbendazim wettable powder 500 to 800 times dilution, or 75% thiophanate-methyl 700 to 1000 times dilution, or 75% chlorothalonil 600 to 800 times dilution and other fungicides, for 5 to 6 consecutive sprays. The several agents should be used alternately, with remarkable control efficacy.
Fusarium wilt
Fusarium wilt is a devastating disease for golden privet. Once it occurs, almost all plants die, so prevention work is key.
After golden privet becomes infected, the leaves wilt and droop, lose their luster, gradually lose green until the leaves turn yellow and dry, until the entire plant dies. The underground part shows dead fibrous roots.
Golden privet fusarium wilt is a fungal systemic infection-type disease. The pathogen overwinters in the soil and diseased plant residues, invades through underground roots, spreads to all parts of the plant through vascular bundles, and multiplies within the vascular bundles, causing blockage or poisoning, which causes the plant to wilt until it dies. After the pathogen infects the roots, it causes the loss of nutrient and water transport functions, thereby causing nutritional deficiency in the plant and then death. High temperature and high humidity favor the occurrence of the disease, so the peak incidence period of golden privet fusarium wilt is from June to August each year, and it continues until October.
Control methods:
This disease should be mainly prevented, with prevention more important than treatment. Strengthen cultivation management, enhance plant resistance, and reduce opportunities for disease occurrence. In mid to late May, spray fungicides for prevention in key affected areas, and protective fungicides such as zineb and mancozeb can be used. At the same time, fungicides such as 50% carbendazim wettable powder 500 to 600 times dilution, or 75% thiophanate-methyl 600 to 700 times dilution, or 75% chlorothalonil 600 to 800 times dilution can be used for drenching, once every 10 to 15 days, for 6 to 7 consecutive drenchings. The several agents should be used alternately, with relatively good control efficacy.