What to Do When Sunflowers Get Bugs? Pest and Disease Control Requires Correct Use of Pesticides

Growing Techniques Jan 1, 1970 0 views

Sometimes we find that the sunflower leaves we worked so hard to grow turn yellow or even wilt and fall off, and such a scene is truly heartbreaking. So what should be done when sunflower leaves turn yellow? Besides mastering the correct sunflower growing methods, another possibility is bugs. So what should be done when sunflowers get bugs? Today I will introduce several commonly used pest and disease control techniques for sunflowers.

What to Do When Sunflowers Get Bugs

There are many insects that may appear on sunflower plants, among which the more harmful and more common ones are: the beet webworm, the sunflower leaf miner, the black velvet chafer beetle, the reticulate sand beetle, and the yellow-bellied tiger moth. When we encounter the problem of sunflowers getting bugs, what should we do? The insects can be removed by following the methods below.

1. Sunflower leaf miner

Potted plants: Spray with trichlorfon or fenitrothion powder once every 3 days until the insects are completely eliminated.

Nursery planting: Dilute 90% trichlorfon emulsifiable concentrate into a 1000-fold solution, then spray it on the leaves and around the plants, and the leaf miners can be successfully eliminated.

2. Reticulate sand beetle

Potted plants: Sprinkle insecticide powder on the soil surface; each sunflower should be given 10-15 grams of insecticide powder.

Nursery planting: Use 1.50% methyl parathion or 0.04% insecticide powder to control the insects, generally at a rate of 30 kg per hectare; a 50% methamidophos emulsifiable concentrate diluted into a 1000-fold solution can also be used for spraying.

3. Beet webworm

Potted plants: This pest can be found with the naked eye and then scraped off. Of course, it should be noted that the eggs of the beet webworm may remain on the leaves, so when removing them, care should be taken to scrape them off as well.

Nursery planting: Spray with a 500-1000 fold solution of 50% phoxim emulsifiable concentrate or 50% fenitrothion emulsifiable concentrate; or dust seedlings with 2.50% trichlorfon powder or 0.04% insecticide powder at 20-25 kg per hectare.

4. Black velvet chafer beetle

Potted plants: This is a very common pest, so in this case what should be done when sunflowers get bugs? The answer is that elm leaves soaked in monocrotophos solution for more than 10 hours can be inserted beside the sunflowers in the afternoon, 2 per plant, and the beetles will not dare to approach the sunflowers.

Nursery planting: Spray with 2% fenitrothion or 2% phoxim powder at a rate of about 15 kg per hectare. A 35-50% methyl thiocyclophosphorus emulsifiable concentrate diluted into a 500-fold solution can also be used for spraying.

5. Yellow-bellied tiger moth

Potted plants: Use trichlorfon powder or carbaryl powder, and note that the amount used should not be too much.

Nursery planting: Dilute 90% crystalline trichlorfon into a 1000-fold solution for spraying, at a rate of 300 kg of solution per hectare.

Pest and Disease Control for Sunflowers

After solving the problem of what to do when sunflowers get bugs, we also need to pay attention to diseases. Among sunflower diseases, the most common and most threatening are sclerotinia rot, powdery mildew, brown spot, and downy mildew, and different control measures should be taken for different diseases.

1. Sclerotinia rot

It needs to be controlled from the following aspects: reasonable crop rotation, strict seed selection, intertillage sterilization, and chemical control. In the early stage of head formation, agents such as procymidone, dimethachlon, vinclozolin, validamycin, or carbendazim can be selected for spray control, with emphasis on protecting the back of the flower head. Because sunflower plants are tall in the later stage and spraying is relatively difficult, the method of going to the field after rain to cut stalks and reduce humidity can also be adopted.

2. Powdery mildew

Adopt large-area crop rotation to reduce infection sources; at the same time, use chemical control, and 0.12-0.14 L per hectare of 400 g/L flusilazole (Fuxing) emulsifiable concentrate can be used. However, it should be noted that when spraying, brassinolide plant growth regulators can be added, as they can promote diseased plants to resume normal growth.

3. Brown spot

A very important point in sunflower pest and disease control is to strengthen cultivation management, such as reasonable close planting, timely weeding, and increased fertilization; of course, we can also use chemicals for control, such as 150 mL per hectare of 0.01% tianfengsu.

4. Downy mildew

If diseased plants are found, they should be pulled out as early as possible and burned in a centralized manner. After the autumn harvest, attention should also be paid to clearing the remains of diseased plants; if it is in the early stage of disease onset, 72% cymoxanil mancozeb wettable powder can be used at a rate of 2.5 kg per hectare.

Summary: Sunflowers getting bugs is something that can be avoided, provided that one fully understands sunflower pest and disease control methods. And if sunflowers are found to have bugs, they should be removed promptly, otherwise the damage to the plants will become greater and greater.

Why Sunflowers Face the Sun and Common Pest Control Methods for Sunflowers

That sunflowers face the sun is a fact even a three-year-old child knows, but why is this so? Is it really because of the endless love and faith in mythological stories? Or is there some other unknown secret? As materialists, we should explore this from a scientific perspective.

Why Sunflowers Face the Sun

The main reason sunflowers turn to face the sun is the influence of light.

Sunflower auxin is distributed at the stem tip and is continuously transported downward, and it is affected by light. Broadly speaking, sunflower auxin is distributed away from the light. The concentration on the side facing the sun is relatively low, but the concentration of auxin on the side away from the light is relatively high, so the side away from the light grows faster, while the side facing the light grows more slowly, causing the stem to bend away from the light, making it always face the sun.

In addition, people also believe that the reason sunflowers turn toward the sun is related to gravity and xanthoxin. In terms of gravity, this means that in the early growth stage and the tender period in the pot, sunflowers turn with the sun; in terms of xanthoxin, this substance can hinder the growth of sunflower cells, and generally the concentration of xanthoxin on the side facing the light is relatively high, so it makes the side of the sunflower facing the light grow more slowly, thereby producing a bend.

Common Pest Control Methods for Sunflowers

1. Beet webworm

When there are few pests, they can be scraped off directly. It is best if you have sharp eyes and can discover the pests when they are eggs and remove them promptly.

When the disease occurs, deltamethrin emulsifiable concentrate or fenvalerate emulsifiable concentrate can be sprayed, diluted with water before spraying.

For diseased seedlings, trichlorfon powder or insecticide powder can be selected and directly sprinkled at the base of the seedlings and in the soil, 10-15 g per plant.

2. Sunflower leaf miner

Leaf miners are relatively stubborn, so trichlorfon powder or fenitrothion powder can be sprinkled once every 2-3 days until they are completely eliminated.

Of course, spraying can also be adopted by diluting trichlorfon emulsifiable concentrate into a 1000-fold solution and spraying it around the plants and on the leaves.

3. Black velvet chafer beetle

Does this seem familiar? Yes, this is a very common pest. When plants have dead leaves and rotten stems, this kind of pest follows the smell. Fenitrothion or phoxim powder can be sprinkled on the soil surface, and care should be taken to spread it evenly.

Spray with a 50% methyl thiocyclophosphorus emulsifiable concentrate solution; when there are many insects, spray directly at the pests.

Select elm leaves with blades, soak them in monocrotophos solution for 10 hours, then insert them beside the sunflowers at 2 p.m., 2-3 per plant. The insects naturally will not dare to approach.

4. Mongolian gray weevil

The simplest method is to spray dichlorvos solution.

Make poisoned soil. Mix methyl parathion powder with wet soil and sprinkle it around the plants; pests will be poisoned when they approach.

5. Reticulate sand beetle

Spray with a 500-fold solution of methamidophos emulsifiable concentrate; when spraying, pay attention to spraying evenly, including the undersides of the leaves.

Sprinkle insecticide powder on the soil surface, 10-15 g per plant.

Growth Habits of Sunflowers

Sunflowers can be planted in all four seasons, with summer and winter being best. Sunflowers grow very quickly, generally taking only about 2 months from planting to flowering, and the longest flowering period is about more than two weeks.

How to Fertilize Sunflowers

1. Base fertilizer

Type: Mainly organic fertilizer, with chemical fertilizer used as little as possible.

Fertilization period and method: For home growing, there is no need to follow agricultural planting. Usually, before planting the small seedlings, mix the fertilizer evenly into the soil. Or after planting, dig several holes 2-3 cm deep around the plant and apply the fertilizer into them.

Fertilizer amount: 5-10 g of organic fertilizer per plant; if the plant is larger, the amount can be appropriately increased.

2. Seed fertilizer

The main purpose of applying seed fertilizer is to strengthen the seedlings, and it should be applied promptly after the seeds germinate. Mainly use calcium phosphate with a small amount of urea.

Usage: 3-5 days after the seeds germinate, sprinkle the fertilizer on the surface of the potting soil. Or apply it 2-3 cm beside the seeds. Combined with sowing, apply organic fertilizer and chemical fertilizer 2-3 cm below the seeds, or 2-3 cm beside the seeds.

3. Topdressing

Type: Mainly nitrogen fertilizer, supplemented by potassium fertilizer. Urea, potassium chloride, and other fertilizers, or decomposed human manure and urine, plant ash, etc., can be selected.

Time: Reasonably topdress according to the plant's growth condition, soil conditions, and the base fertilizer applied. However, topdressing is mainly concentrated in the period from sunflower bud formation to flowering.

Method: Dig small pits 10-15 cm away from the sunflower and apply fertilizer. Pay attention to the depth of fertilization, avoid direct contact with the root system, and apply it in the moist layer, as this helps the fertilizer exert its effect.

4. Foliar spraying

Sunflower foliar fertilizer is mainly sprayed after bud formation. After bud formation, spray zinc, copper, manganese, and molybdenum solutions, and after flowering, spray nitrogen, phosphorus, and potassium solutions, which can make the flowers bright and the leaves tender green.

Sunflowers facing the sun are affected by xanthoxin in their bodies, thereby affecting the growth angle of the sunflower, but the arrangement of the creator is indeed a miracle of the sunflower's existence. Therefore, from any angle, the existence of the sunflower has extraordinary significance.

Complete Guide to Common Pest Control for Sunflowers

Beet webworm