How to control corn borer with Beauveria bassiana?

1) In the spring maize area of Northeast China, the overwintering larvae were eliminated by sealing the corn straw stacks with Beauveria bassiana. In early to mid-May, before the pupation of the overwintering corn borer larvae, 10 20 grams of Beauveria bassiana (30 billion spores per gram) were sprayed and sealed with powder per cubic meter.

Corn borer. 2) In the peak hatching period of corn borer eggs in the field, Beauveria bassiana granules are sprinkled directly into the corn heart leaves, or Beauveria bassiana powder is mixed into poisonous soil and sprinkled into the bell mouth, and the dosage is 750 grams of Beauveria bassiana powder (30 billion grams) per hectare and 30 kg of soil (50 grams of soil mix 2 kg per mu). Because the pathogenicity of Beauveria bassiana is affected by temperature, humidity, bacterial volume, insects, insect age, etc., in use, one is to choose a strain against corn borer; Second, it is necessary to choose the appropriate application time (temperature 23 26); Third, it is necessary to choose the right area (field relative humidity 80% 100%), and it is difficult to play a good control effect in dry climate areas; Fourth, it is necessary to choose the young larval stage, the lower the larval stage, the more likely it is to be infected.

1. Biological control.

There are many kinds of natural enemies of corn borer, mainly parasitic egg red-eyed wasps, black egg wasps, parasitic larvae parasitic flies, Beauveria bassiana, bacteria, viruses, etc. Predatory natural enemies include ladybugs, walking insects, grass dragonflies, etc., all of which have a certain inhibitory effect on the insect population. The main control methods are the egg killing of red-eyed wasps, the use of Beauveria bassiana to treat the borer and the use of Bacillus thuringiensis to control the borer.

2. Chemical control.

1. Prevention and control of the cardiac lobe stage. At present, the application of pesticides in the bell at the end of the heart leaf stage of corn is still the best pesticide control method to control the first generation of spring maize and the second generation of summer maize corn borer in northern China.

2. Prevention and control at the panicle stage. When the spike rate reaches 10% or there are 50 insects in the spike filament, it should be controlled once in the peak silking period, and the nymph spike rate exceeds 30%, and it needs to be controlled again after 6-8 days.

3. Trapping adult insects.

According to the phototaxis of the adult corn borer, a large number of adults can be trapped. During the occurrence of overwintering adult insects, a water basin trap was set up in 15 hm2 in wheat field with a trap dose of 20ug to trap and kill a large number of male insects, which significantly reduced the control pressure of the first generation.

1. Agricultural prevention and control technologyPromote straw returning to the field, or use it as manure, feed, fuel, etc., to reduce the overwintering base of corn borer.

2. Biological control technology:Vigorously promote biological control technologies such as Beauveria bassiana. Beauveria bassiana biological control can be done by using Beauveria bassiana sealing technology (note, this technology needs to be controlled and controlled), or made into Beauveria bassiana granules to be put in the large flare period, both of which need to master the time of delivery to achieve the effect.

3. Physical and chemical inducement and control technologyUsing the phototaxis and chemotaxis of corn borer to make sexual attractants, trapping and killing corn borer adults before laying eggs can effectively reduce the amount of eggs and reduce the harm of corn borer.

4. Chemical control technologyUse the sprinkle chemical agents (such as carbofuran, phosphine, etc.) to kill the heart leaf stage corn larvae, in the corn heart leaf stage, the first and second generation of hatched larvae in the spring and summer corn heart leaves to feed for the damage when the granules are applied, the dosage is 1 2 kg per mu, add 5 times of fine river sand mixed and sprinkled into the bell mouth.

5. Spraying insecticide control technology:At the budding stage of the male panicle, spray with fenvalerate EC or deltamethrin EC. In the intercropping field between wheat and corn, octathion emulsifiable concentrate can also be used to control corn borer.

Corn borer habits:

Adults are diurnal and nocturnal, phototaxis, and have strong ability to fly and spread. Adults mostly emerge at night, do not need to supplement nutrition after emergence, and can mate on the same day after emergence. Male moths have the habit of mating multiple times, and most female moths only mate once in their lifetime.

Female moths begin laying eggs one to two days after mating. Each female moth lays 10 20 eggs, about 300 600 eggs.

After hatching, the larvae first cluster near the egg shell and begin to disperse after about an hour. The larvae have a total of 5 instars, and have glycotaxis, tactile tropism, humidity tropism and negative phototaxis, and like to latent harm. After the larvae are old and mature, they mostly pupate in their harmful places, and a few larvae crawl out of the stalks to pupate.

Summary. The main control measures for corn mildew disease are as follows:1

Good field management: Regularly remove weeds in the field, keep the field ventilated and exposed to sunlight, and prune the leaves of the plants in time to reduce the chance of germ growth. 2.

Planting disease-resistant varieties: Choose corn varieties with strong disease resistance for planting, which can reduce the invasion of pathogens and improve the disease resistance of corn plants. 3.

Reasonable fertilization: Scientific and reasonable fertilization can enhance the immunity of corn plants and improve the ability to resist diseases. However, care should be taken to avoid excessive nitrogen fertilizer application to reduce the chance of pathogen growth.

4.Disease monitoring and early warning: regularly inspect the field to observe the growth of plants and leaf changes, and take timely prevention and control measures to avoid the spread of diseases once disease symptoms are found.

In short, through reasonable field management, selection of disease-resistant varieties, reasonable fertilization and disease monitoring, the occurrence of maize disease can be effectively prevented and controlled, and the stability of maize yield and farmers' income can be guaranteed. Hope this helps, if you have any other questions, please feel free to ask!

The main control measures for corn mildew disease are as follows:1Good field management:

Remove weeds in the field regularly, keep the field ventilated and exposed to sunlight, and prune the leaves of the plants in time to reduce the chance of germ growth. 2.Planting disease-resistant varieties:

Corn varieties with strong disease resistance can be selected for planting, which can reduce the invasion of pathogens and improve the disease resistance of corn plants. 3.Proper fertilization:

Scientific and reasonable fertilization can enhance the immunity of corn plants and improve the ability to resist diseases. However, care should be taken to avoid excessive nitrogen fertilizer application to reduce the chance of pathogen growth. 4.

Disease monitoring and early warning: regularly inspect the field to observe the growth of plants and leaf changes, and take timely prevention and control measures to avoid the spread of diseases once disease symptoms are found. In short, through reasonable field management, selection of disease-resistant varieties, reasonable fertilization and disease monitoring, the occurrence of corn mildew disease can be prevented and controlled, and the stability of corn yield and farmers' income can be guaranteed.

Can you add, I don't quite understand it.

The main prevention and control measures of corn mildew disease include good field management, planting disease-resistant infiltration varieties, reasonable fertilization and disease monitoring. Through these measures, the occurrence of corn mildew disease can be effectively prevented and controlled, and the corn yield and farmers' income can be guaranteed. If you have any other questions, please feel free to ask!

Control measures for corn borer: (1) Agricultural control. After the autumn harvest or before April in spring, treat the straw, cob, root stubble and weeds such as Xanthus and nightshade of corn and sorghum to eliminate the overwintering larvae and reduce the number of insect sources.

Set up an early-sowing insect trap field to lure adult worms to lay eggs, and then concentrate on extermination.

Booby-trap adults. The phototaxis of the adults can be used to trap the adults at night with a black light, a high-pressure mercury lamp, or a frequency lamp.

2) Biological control.

Unleash the Red-Eyed Bee. In the oviposition period of corn borer, 12,000 red-eyed bees are released every 667 m2 (mu), which are released in two times, which can make the egg parasitic rate reach more than 68%. It can also be used for long-distance cocoon bees, 700 heads per 667 meters 2 (mu).

Use BT granules (bacterial pesticides) to treat borer. At the end of the corn heart leaf, bt granules were sprinkled into the heart leaves, with 700 grams per 667 meters 2 (mu), and the control effect was good.

In addition, Beauveria bassiana can also be used to treat borers or corn borer sex pheromones to attract insects.

3) Pharmaceutical prevention and control.

Sprinkle granules. At the end of the corn heart leaf, with 1% rate sulfur and phosphorus granules or 3% Guangxidan granules, every 667 meters 2 (mu) with 1 2 kg mixed with 5 times of fine sand mixed into the bell mouth. Or mix 3 4 kg of fine sand with 250 grams of Pyroxin No. 1 granules, and sprinkle 1 gram per plant into the heart leaves.

You can also use kung fu granules to mix 10 times the fine slag, and sprinkle each gram into the bell mouth, which also has a good control effect.

In addition, it can also be directly irrigated with phosphine and other medicinal solutions.

Drip at the adult stage. After corn earing, 50% phosphine or 40% hydroamidophos emulsifiable concentrate 1000 times can be sprayed or dropped on the top of the female ear and the leaf axils of the upper and lower leaves of the female ear, which can effectively protect the female ear from insect pests.

(1) Hazard status: The newly hatched larvae gather to eat heart leaves and young leaves; Slightly larger is the stem and fruit.

2) Morphological characteristics Adult wingspan 25-35 mm, yellowish-brown, female body stout, forewings bright yellow. The male moth is thin and small, the wing color is slightly darker than that of the female, the head, thorax, and forewings are yellowish-brown, the dorsal surface of the thorax is light yellowish-brown, the inner transverse line of the forewings is dark brown and corrugated, the inner side is yellowish-brown, the base is brown, and the hindwings are light brown.

3) Prevention and control methods.

Timely treatment of the straw of the overwintering host after harvest must be completed before the overwintering larvae pupate and emerge.

From the beginning of the corn borer to the peak of the egg-laying period, the red-eyed bee was released 2 3 times, and 12,000 heads were released per mu.

Spray 600 times of 25% chlorpyramide No. 3 suspension, or 200 ml of emulsion containing more than 10 billion spores per gram per mu of emulsion, which can also be made into granules for sprinkling.

Beauveria bassiana powder is used to spray 100 grams of bacillus powder containing 5 billion 10 billion spores per gram per gram before pupation of corn borer.

Mix 100 kg of fine soil with 1 kilogram of green worm fungus powder and apply it to the heart leaves.

The black light was used to lure moths combined with field egg checking, and the number of eggs spawned, hatching progress and field hazards were mastered, and the mosaic plant rate at the end of spring maize heart leaves reached 10%. More than 20% or more than 30 eggs need to be prevented again, summer corn heart leaf end prevention 1 time, ear stage when the ear rate of 10% or 100 spike filaments have 50 insects to be immediately controlled, the agent can be selected 50% borer single soluble powder 100 grams of water irrigation heart leaves, or kung fu granules per plant grams. It can also be sprayed with 4000 times of pyrethrin EC, or 40% synergistic rapid kill or 5% Lefrin EC 2000 times, in addition, the retention fumigation method can also be selected.

Prevention and control measures.

Prevention and control during the overwintering period.

Overwintering host straw is treated, and overwintering larvae pupate in spring. The pre-feathering treatment is complete.

Prevention and control before tasseling.

Before the first hole is seen in the heart leaves of corn and the young larvae swarm the heart leaves without being bored into the stalks, the zinc sulfur and phosphorus granules or carbofuran granules used can be directly dropped in the bell mouth to obtain better control effects.

Spike stage control. After the filaments wilt, cut off the filaments, and use 90% trichlorfon kilograms, 150 kilograms of water, and 250 kilograms of clay to make a slurry and apply it to the cut, and the effect is good; It can also be used with 50% or 80% dichlorvos emulsion 600 800 times, or 90% trichlorfon 800 1000 times, or 75% octathion emulsion 1000 times, drop on the top of the female spike, the effect is also good.

Manual removal of the egg mass.

It was found that the egg masses of corn borer were manually removed and destroyed outside the field.

Biocontrol. Unleash the Red-Eyed Bee.

The red-eyed wasp is an egg-parasitic insect predator. It can parasitize the eggs and larvae of a variety of agricultural, forestry, fruit and vegetable pests. It is used for the prevention and control of corn borer, which is safe, non-toxic, pollution-free, simple and effective.

Release red-eyed bees during the egg-laying period of corn borer, and choose a large area on sunny days to release bees. The amount and frequency of bee release are determined according to the number of moth eggs. Generally, 150,000 300,000 heads are released per hectare, released in two parts, 45 points per hectare, select robust corn plants at the point, on a leaf surface in the middle of it, tear it in half along the main vein, take half of it and put it on the bee card, gently roll it into a cylinder along the direction of the stem, the leaves should not be rolled too tightly, and the bee card will be nailed firmly with threads and nails.

It should be mastered in the late stage of the pupa of the red-eyed bee, released when the bees are released, and the bee card can appear in large numbers after hanging it in the field for 1 day.

Using Beauveria bassiana:

Beauveria bassiana can parasitize corn borer larvae and pupa. Before the overwintering larvae begin to resuscitate and pupate in early spring, the remaining straw is sprayed with Beauveria bassiana powder to seal the stack. The method is to use 100g of bacterial powder containing 10 billion spores per gram per cubic meter of straw stack, spray a point, that is, insert the powder pipe into the stack, shake the handle, and fly out when there is fungus powder on the stack surface.

Beauveria bassiana loses heart Generally in the middle of corn heart leaves, use 500g of Beauveria bassiana powder with a spore content of 5 billion 10 billion to apply 2g to cinder granules 5, each plant can effectively control the harm of corn borer.

BT wettable powder During the incubation period of corn borer eggs, the field is sprayed with 200 times of BT wettable powder, a BT emulsion with 10 billion spores per milliliter, to effectively control insect pests.

1.Agricultural control: (1) Before the overwintering larvae emerge, treat the stems of overwintering hosts such as corn, sorghum and cotton to eliminate the source of overwintering insects; (2) planting booby-trap fields; (3) Breeding insect-resistant varieties.

2.Biological control: (1) release the red-eyed wasp (Trichogramma ostriniae pang et chen) during the peak oviposition period of corn borer moth to kill eggs; (2) Beauveria bassiana bafsama granules were applied to the heart leaf bell in the middle of the corn heart leaf to kill the larvae.

3.During the adult stage, black light or sexual attractants are used to trap and kill.

4.Pharmaceutical control: (1) granule control at the end stage of corn heart leaves:

1) 1% 1605 granules, grams per plant, sprinkled into the heart leaf flare; 2) 25% carbaryl wettable powder is mixed with fine soil at 1:50 to form poisonous soil, and 2 grams per plant is sprinkled into the heart leaves; 3) 5% methyl isothion granules are mixed with cinders at 1:6, 2 grams per plant, and sprinkled into the heart leaves; 4) 1:

15 Mix cinders, 1 gram per plant and sprinkle into the heart leaves. (2) Corn ear stage pesticide protection: 1) Perfusion of male ears with liquid medicament:

Commonly used agents are 18% insecticidal aqueous agent 500 times, 50% dichlorvos emulsifiable concentrate 800 times, 90% trichlorfon crystals or 50% phoxanthion emulsifiable concentrate 800 1000 times, 50% ethionphos emulsifiable concentrate 1000 times, etc. These solutions were perfused with 10 ml per plant for maize ears at the open male stage. 2) Liquid medicine dot filigree:

800 times of 50% dichlorvos emulsion was put into a bottle with a thin plastic tube, and when the corn pollination was finished and the larvae had not yet concentrated the filaments, a few drops of the liquid were dropped on the base of the filaments at the top of the female panicle to fumigate the larvae.