Prevention of early deciduous apple disease
2018-04-26 14:00:35
In recent years, many early epidemics of apple larvae in Shaanxi Province led to the early fall of leaves, which not only seriously affected the yield and quality of apples, but also led to declining tree vigor, which in turn caused the apple tree rot disease to increase, causing great damage to apple production. .
Early defoliation mainly includes two diseases, one is apple brown spot and the other is apple deciduous disease. In the fruit area where Fuji apples are the main cultivars, the occurrence of brown spot disease in apples is serious. In the fruit area where the Marshal is the main apple cultivar, brown spot and spotted larvae may be more serious.
A. Comparison of two diseases
1. The occurrence of brown spot mainly damages old leaves and also damages fruits and branches; spotted leaf disease mainly damages young leaves, and also harms fruits and branches.
2. Characteristics of leaf lesions Brown spot lesions are brown in the center, green in the periphery, and yellow in the periphery. There are small black spots on the lesions, which may be needle-like or ring-shaped. Spotted deciduous lesions are nearly round, reddish-brown, with no black spots, and sometimes with long black backs.
3. Two winter diseases of pathogens are mainly wintering on fallen leaves.
4, the occurrence of characteristics of brown spot disease in late May to early June for initial infection. July-August is popular with rain. Distinctive deciduous disease has two peak periods of spring shoots and autumn shoots. After flowering, it was rainy and the incidence of spring shoots was heavy. From late June to July, it was rainy and heavy in autumn.
5, the response to drugs The effective drugs for brown spot is more, but the effect of polyoxin is extremely poor; the specific effects of polymyxins of spotted leaf disease, copper preparations, carbendazim, and ketamine are almost ineffective.
6. Responses to Apple Varieties Most apple varieties of the brown spot disease are susceptible; the Marshal species of the spotted leaf disease is highly susceptible, the Golden Crown and some new varieties are also susceptible, and the Fuji lineages are rarely affected.
7, the characteristics of prevention and control thoroughly remove leaves is very important for the prevention and control of both diseases. There are major differences between the two types of diseases. The first drug of brown spot from late May to early June is very important; continuous spraying in the rainy season from July to August is the key to control the epidemic. Spotting defoliation along the coast, along the lake, along the river and other high-humidity fruit areas mainly prevent the occurrence of spring shoots; from June to July, the rainy fall attention to the prevention and treatment of the shoots. Inland fruit areas generally do not need to control the spring period, the main control of the incidence of autumn shoots.
Second, the apple brown spot prevention and control technology for many years of investigation has proved that the fruit spot in early fruits of apple in Shaanxi Province is the focus of control of brown spot, the main measures are as follows.
1, completely clear the deciduous apple brown spot pathogens mainly in the diseased leaves overwintering, leaf rot decomposition, bacteria will also die. Thorough removal of fallen leaves can significantly reduce the amount of orchard bacteria, reduce or delay the occurrence of diseases, is very important for the control of the growth period. The time for clearing the fallen leaves is from the time of defoliation to before germination. The method of clearing is to plant the trees first, then under the trees, and then thoroughly remove them and then bury them or bury them in a centralized manner. Partial removal has a certain effect, a large area at the same time clear better.
2. The key to chemical control of pesticides on apple brown spot disease is prevention and treatment. The first is spraying 7-10 days before the onset of disease to prevent the initial infection of overwintering pathogens; the second is spraying continuously during the rainy season to control the epidemic of diseases; Spraying technology to ensure the quality of spraying; Fourth, the use of effective drugs to ensure the effectiveness of spraying.
(1) It is very important to spray for the first time. The brown spot pathogens are overwintering on diseased deciduous trees. From May to early June, as long as there is rain, the germs can be transmitted through the rain and splashed to the near-ground leaves. The spores germinate and invade the interior. Causes the onset of the lower canopy leaves. These newly infected diseased leaves become the basic pathogens of the epidemic in that year. Years of prevention and treatment practices have proved that it is very important to control late stage infection by spraying medicine and preventing initial infection.
(2) Spraying in the rainy season is the key. Brown spot is an epidemic disease caused by wind and rain. From July to August, it is rainy, the disease is serious, and from July to August, it is less rainy. It is very difficult for the disease to occur seriously. The farmers should pay close attention to the rainfall from July to August on the basis of the first spraying, and spray pesticides in time to control the epidemic. . In general years, 7 to 8 doses should be sprayed 2-4 times. In recent years, the main reason for the serious occurrence of brown spot in Shaanxi Province was caused by the majority of fruit growers neglecting to spray the medicine after bagging.
(3) Improving the quality of spraying The quality of sprays has a great effect on control. The so-called spray, the main indicators are three, one is the amount of water per mu. The age of orchards should reach 200-300 kilograms per acre, and the amount of water is too small to have good results. The second is thorough and uniform. Brown spot pathogens mainly invade from the back of the leaves. Spraying should pay attention to the uniform medicine on the back of the leaves, and only spray the front of the leaves. It is difficult to achieve the desired effect. The third is the degree of atomization. The higher the degree of liquid atomization, the better the control effect.
(4) There are many kinds of effective agents for effective control of brown spot, and many years of experiments and production practices at Shaanxi Plant Protection Station have proved that 80% of Mustelis Mz-120 has 600-800 times the best effect, compared with imported similar drugs. The control effect is quite, but the price is cheap, and it is the key promotion product of the National Agricultural Technology Promotion Center of the Ministry of Agriculture. In addition, 10% Shigao (difenoconazole) water dispersible granules or emulsifiable concentrate 6000 times, 25% true high microemulsion 10000 times, Yibao 1000-1500 times, 70% thiophanate-methyl 1200-1500 times, 50 % 800-1000 times of carbendazim. The safety of the above agents is very good, and use before bagging will not harm young fruit. After bagging, the above agents can also continue to be used. (Hebei Agricultural University professor) Author: Hou Baolin
Early defoliation mainly includes two diseases, one is apple brown spot and the other is apple deciduous disease. In the fruit area where Fuji apples are the main cultivars, the occurrence of brown spot disease in apples is serious. In the fruit area where the Marshal is the main apple cultivar, brown spot and spotted larvae may be more serious.
A. Comparison of two diseases
1. The occurrence of brown spot mainly damages old leaves and also damages fruits and branches; spotted leaf disease mainly damages young leaves, and also harms fruits and branches.
2. Characteristics of leaf lesions Brown spot lesions are brown in the center, green in the periphery, and yellow in the periphery. There are small black spots on the lesions, which may be needle-like or ring-shaped. Spotted deciduous lesions are nearly round, reddish-brown, with no black spots, and sometimes with long black backs.
3. Two winter diseases of pathogens are mainly wintering on fallen leaves.
4, the occurrence of characteristics of brown spot disease in late May to early June for initial infection. July-August is popular with rain. Distinctive deciduous disease has two peak periods of spring shoots and autumn shoots. After flowering, it was rainy and the incidence of spring shoots was heavy. From late June to July, it was rainy and heavy in autumn.
5, the response to drugs The effective drugs for brown spot is more, but the effect of polyoxin is extremely poor; the specific effects of polymyxins of spotted leaf disease, copper preparations, carbendazim, and ketamine are almost ineffective.
6. Responses to Apple Varieties Most apple varieties of the brown spot disease are susceptible; the Marshal species of the spotted leaf disease is highly susceptible, the Golden Crown and some new varieties are also susceptible, and the Fuji lineages are rarely affected.
7, the characteristics of prevention and control thoroughly remove leaves is very important for the prevention and control of both diseases. There are major differences between the two types of diseases. The first drug of brown spot from late May to early June is very important; continuous spraying in the rainy season from July to August is the key to control the epidemic. Spotting defoliation along the coast, along the lake, along the river and other high-humidity fruit areas mainly prevent the occurrence of spring shoots; from June to July, the rainy fall attention to the prevention and treatment of the shoots. Inland fruit areas generally do not need to control the spring period, the main control of the incidence of autumn shoots.
Second, the apple brown spot prevention and control technology for many years of investigation has proved that the fruit spot in early fruits of apple in Shaanxi Province is the focus of control of brown spot, the main measures are as follows.
1, completely clear the deciduous apple brown spot pathogens mainly in the diseased leaves overwintering, leaf rot decomposition, bacteria will also die. Thorough removal of fallen leaves can significantly reduce the amount of orchard bacteria, reduce or delay the occurrence of diseases, is very important for the control of the growth period. The time for clearing the fallen leaves is from the time of defoliation to before germination. The method of clearing is to plant the trees first, then under the trees, and then thoroughly remove them and then bury them or bury them in a centralized manner. Partial removal has a certain effect, a large area at the same time clear better.
2. The key to chemical control of pesticides on apple brown spot disease is prevention and treatment. The first is spraying 7-10 days before the onset of disease to prevent the initial infection of overwintering pathogens; the second is spraying continuously during the rainy season to control the epidemic of diseases; Spraying technology to ensure the quality of spraying; Fourth, the use of effective drugs to ensure the effectiveness of spraying.
(1) It is very important to spray for the first time. The brown spot pathogens are overwintering on diseased deciduous trees. From May to early June, as long as there is rain, the germs can be transmitted through the rain and splashed to the near-ground leaves. The spores germinate and invade the interior. Causes the onset of the lower canopy leaves. These newly infected diseased leaves become the basic pathogens of the epidemic in that year. Years of prevention and treatment practices have proved that it is very important to control late stage infection by spraying medicine and preventing initial infection.
(2) Spraying in the rainy season is the key. Brown spot is an epidemic disease caused by wind and rain. From July to August, it is rainy, the disease is serious, and from July to August, it is less rainy. It is very difficult for the disease to occur seriously. The farmers should pay close attention to the rainfall from July to August on the basis of the first spraying, and spray pesticides in time to control the epidemic. . In general years, 7 to 8 doses should be sprayed 2-4 times. In recent years, the main reason for the serious occurrence of brown spot in Shaanxi Province was caused by the majority of fruit growers neglecting to spray the medicine after bagging.
(3) Improving the quality of spraying The quality of sprays has a great effect on control. The so-called spray, the main indicators are three, one is the amount of water per mu. The age of orchards should reach 200-300 kilograms per acre, and the amount of water is too small to have good results. The second is thorough and uniform. Brown spot pathogens mainly invade from the back of the leaves. Spraying should pay attention to the uniform medicine on the back of the leaves, and only spray the front of the leaves. It is difficult to achieve the desired effect. The third is the degree of atomization. The higher the degree of liquid atomization, the better the control effect.
(4) There are many kinds of effective agents for effective control of brown spot, and many years of experiments and production practices at Shaanxi Plant Protection Station have proved that 80% of Mustelis Mz-120 has 600-800 times the best effect, compared with imported similar drugs. The control effect is quite, but the price is cheap, and it is the key promotion product of the National Agricultural Technology Promotion Center of the Ministry of Agriculture. In addition, 10% Shigao (difenoconazole) water dispersible granules or emulsifiable concentrate 6000 times, 25% true high microemulsion 10000 times, Yibao 1000-1500 times, 70% thiophanate-methyl 1200-1500 times, 50 % 800-1000 times of carbendazim. The safety of the above agents is very good, and use before bagging will not harm young fruit. After bagging, the above agents can also continue to be used. (Hebei Agricultural University professor) Author: Hou Baolin