Comprehensive prevention and control technology of white and rust to help crops grow healthily
High Leather
Bletilla striata is a perennial herbaceous plant of the family Orchidaceae. There are 6 species of Blyurella worldwide, mainly in Myanmar, China and Japan. There are 4 species in the mainland, namely B. alba, B. japonica and B. ochracea), B. Hua Bai and B. sinensis) and B. formosana. In the mainland, it is mainly distributed in the south of the Yangtze River, and in the mountainous areas of southern Anhui Province, the Dabie Mountains, and the areas along the Yangtze River. Among the 4 species of B. alba, only B. alba is included in the Chinese Pharmacopoeia. It has a variety of pharmacological activities such as hemostasis, antitumor, antibacterial, promoting wound healing, and promoting cell growth. The traditional Chinese medicine made of white and false bulbs is sun-dried, which has the effects of astringent hemostasis, swelling and muscle growth. Dried flowers or dried tubers can also be made into tea. White and white extract is an excellent biological polymer material and excellent pharmaceutical excipients. It also has great utilization value in food, textile printing and dyeing, special coatings and daily chemicals. White and purple flowers, 18~60 cm high, can be used for roadside, parks, squares, flower beds greening, or placed in the park between rocks, beside the water system, or used to decorate gardens and flowers, or as a potted plant to enjoy.
Most of the land in the mountainous areas of southern Anhui is distributed on both sides of the valley and the larger river, and the humidity is higher in the morning and evening, and the field planting white and white rust is easy to spread, while the woodland is generally more slopeous, and the upper layer is covered by the canopy of trees, and the humidity under the forest is high, and the white and rust are more likely to spread. Once the occurrence of white and rust will affect the growth of white and false bulbs, if the prevention and control is not timely, it will cause a serious reduction in production and affect the economic income of the operator.
In order to solve the technical problems of rust control in field and understory planting, the author has carried out a series of studies on the occurrence of rust and its comprehensive prevention and control technology after planting, and has been successful.
1 Symptoms and source of white and rust
White and rust mainly damage white and leaves. In the early stage, yellow summer spores were scattered on the back of the infected leaves, and small pale yellow lesions appeared on the front. In the middle stage, the summer spores on the back of the leaf are piled up in large pieces, and pale yellow lesions can be seen on the front. In the later period, yellow-brown winter spore piles gradually appeared in and around the summer spore pile, and the winter spore pile was solitary or clustered together. Winter spores are oblong and arranged in a single layer in a palisade-like shape, and the surface is covered with a transparent sheath-like substance. When the damage is severe, it can make the white leaves turn yellow or even die.
The pathogen of white and rust is a fungus of the class Rust Fungus of the class Rust Fungus of the class Busidiomycetes, the summer spores are scattered, round or oval, the length-width ratio is less than 2:1, yellow, there is a layer of reticulation and wart on the surface; the summer spore pile can be combined into a large block, and it is raised in the back of the leaf, causing the front of the leaf to be covered with light yellow spots; the winter spores are oblong, the length-width ratio is less than (4~5):1, yellow-brown, there are infertile cells at the bottom, and the single layer is arranged. Winter spores spend the winter in the soil in September ~ October, which is similar to the monocotyledon rust pathogens such as wheat and corn, and has the characteristics of fast propagation speed and high degree of harm.
2. Comprehensive prevention and control of white and rust
2.1 Principles of prevention and control
Adhere to the principle of prevention. In autumn and winter, cut weeds (shrubs), plough the field or clear the litter under the forest to reduce the occurrence of rust. Strengthen fertilizer and water management, adopt formula fertilization, apply fully decomposed organic fertilizer, and appropriately increase phosphorus and potassium fertilizer to improve plant disease resistance. Once the diseased leaves are found during the growth period of white and seedlings, they should be cut off in time, and the whole plant should be buried or burned after the serious uprooting. Priority is given to the use of biological pesticides, and it is strictly forbidden to use highly toxic, highly toxic, high residue pesticides and teratogenic, mutagenic and other pesticides; adhere to the rotation of drugs, give priority to the rotation of pesticides with mutual resistance; adhere to one spray and multiple prevention, and reduce the number and amount of drugs as much as possible.
2.2 Prevention and control methods
2.2.1 种苗培育期防控
Before planting seedlings or sterile domesticated seedlings in the field or understory, at least apply pesticides (50% carbendazim wettable powder) 2~3 times, which can effectively prevent the occurrence of rust and do a good job in the prevention and control of rust during the cultivation period of white and seedlings from the source.
After the aseptic seedlings reach the acclimation conditions, the seedlings can be refined, the seedlings can be washed, the washed seedlings are soaked in 1 000 times liquid chlorine dioxide solution for 3~5min disinfection, dried and planted in a hole tray filled with a moist substrate (perlite 1: peat 2: vermiculite 1), after planting, it is watered and sterilized with less than 1 000 times liquid chlorothalonil solution, and then sterilized once every 15~20 days until it is planted in the shed.
Within 60 days before planting, the seedlings should be watered or sprayed 3 times with the above concentration of pesticides to ensure that they do not carry pathogens before planting.
2.2.2 Prevention and control of white and planting links
Seedlings sown in the ground or sterile domesticated seedlings should be sprayed with 32.5% benzoxystrobin 1 500 times or 75% oxime tebuconazole 2 000 times before planting after seedlings are planted for prevention and control, and can also be sprayed with 1 500 times of shenzimycin or 1 000 times of tetramycin for prevention and control. Spray evenly, and the surface of the leaves can be planted after the moisture is dried.
2.3 Prevention and control of white and growth periods
From the year of planting to the fourth year, the monitoring of white and rust is carried out every year. Once white and rust is found, it is necessary to carry out pesticide prevention and control in time to ensure that rust does not occur during the entire growth period.
2.3.1 Prevention and control of field white and rust
(1) Application time and equipment. In late March or mid to late April of the year of planting, pesticide prevention should be taken before or at the beginning of the disease of B. spp., and field observation should be made every 10~15 days, and when a small number of yellow spots appeared behind the leaves, pesticide control should be carried out in time. In the 3~4th year of planting, combined with cultivating and weeding, the white and rust should be observed, and the rust should be prevented and controlled in time. The number of pesticide applications depends on the degree of rust occurrence, and the pesticides are generally applied 2~3 times a year. The first is in mid-to-late April (after the leaves of the seedlings have grown together), the second is in early to mid-May (the peak growth period of the seedlings), and the third is from late May to early June. The applicator is a knapsack electric sprayer (water capacity ≦ 15 kg) or a high-pressure gasoline sprayer (four-stroke sterilizer).
(2) Agents and application methods. In order to promote the growth of white and white grains, 1 packet of "Good Harvest" foliar fertilizer is added to each barrel of medicine when dispensing. First, put 1 package of "good harvest" foliar fertilizer in a sprayer and add a small amount of water to dissolve, then put 30 mL of 20% triazolone emulsion and 15mL of 25% pyraclostrobin suspension into them, and add an appropriate amount of water to mix the liquid medicine. Spray the liquid from the white to the ground in order on the front and back of the white leaves. The liquid medicine should be sprayed evenly until the liquid medicine is moistened on the front and back sides of the leaves without dripping. Do not miss spraying and do not repeat spraying, so as not to cause waste of liquid medicine and increase labor costs.
2.3.2 Prevention and control of understory white and rust
(1) The time and frequency of application. In mid to late April of the year of planting, monitor the understory and the understory and the yellow spots on the back of the leaves, and carry out pesticide prevention and control in time, generally 2~3 times / year. The first time was in late April, after the leaves were full, the second time was in mid-to-late May, and the third time was in late May to early to mid-to-mid-June.
(2) The application equipment and dispensing method are the same as above.
(3) Application method. 3~5 people as a group, each person carries 1 knapsack sprayer filled with liquid medicine, lined up in a row (the distance between each applicator is about 3 m), apply the pesticide along the contour line or along the edge of the grass belt, and require the liquid to be evenly sprayed to the front and back of the white leaves. After the first bucket of liquid medicine is applied, use a branch to insert it into the sprayed place to make a mark, so that the operator can continue to apply the medicine when applying the second barrel of medicine, so as to avoid repeated application or missed application. Finish one plot and spray another.
(4) Quality requirements. It is required that the white and the front and back sides of the leaves should be sprayed with the liquid. Because there may be a small number of weeds in the planting plot, some of the liquid medicine will be blocked by the weeds, resulting in a small number of leaves that cannot be sprayed, which affects the control effect. Therefore, spraying should be serious, careful and even, and avoid missing and repeated application. When applying pesticides, it is necessary to spray the plots that have just finished tending and management, near, small slope, low altitude and serious disease, and then spray the plots with light disease, far away, large slope and high altitude according to the water source, manpower, site conditions, etc.
3 Conclusion
With the increase of market demand year by year, its benefits are also getting better year by year, the enthusiasm of forest farmers and enterprises to plant Britain has improved, and the planting scale of B. barley has gradually expanded. In recent years, the planting areas of southern Anhui have been more or less affected by white and rust. Once the rust disease occurs, it will inevitably affect the output and quality of the products, and have a negative impact on the development of the industry. Therefore, in the process of planting and management, it is necessary to strengthen the monitoring and comprehensive prevention and control of B. leuticis to ensure that rust does not occur or occurs less, improve the yield and planting efficiency of B. spp., and promote regional economic development.