What pesticides should be used for peanuts (Fabaceae) at the seedling stage and full-bloom stage, for yellow leaves and cotton bollworm, to achieve high yield?

Peanut (a dicot) generally refers to the groundnut (a Fabaceae plant), an annual herbaceous plant. Its pods swell and the pod walls are thick, with the flowering and fruiting period from June to August. So what pesticides should be used at the seedling stage, full-bloom stage, for yellow leaves and cotton bollworm? How can high yield be achieved?

What pesticides should be used for peanuts at the seedling stage, full-bloom stage, for yellow leaves and cotton bollworm? How can high yield be achieved?

I. Full-bloom stage:

1. Intertillage and earthing up: Earthing up toward the pegs can thicken the soil layer, allowing the pegs to enter the soil earlier

2. Timely watering: During this period, peanuts are very sensitive to moisture, so water promptly.

3. Control plant growth to keep steady growth: The soil in peanut fields is rich in nitrogen fertilizer. Under high temperature and frequent rain, peanuts tend to grow excessively, and then easily lodge, causing severe yield reduction.

4. Timely control of pests and diseases: The main pests and diseases in the mid-growth stage of peanuts include leaf spot disease, white grubs, and cotton bollworm.

Chemical control:

In the middle and late stages of peanut growth, the main prevention targets are peanut leaf spot disease and brown spot disease. For control, 70% thiophanate-methyl wettable powder at 800 times dilution, or 50% carbendazim wettable powder at 800 times dilution can be used for spraying, once every 7-10 days, for 2-3 consecutive sprays, which can achieve good control results. The main insect pests include cotton bollworm, aphids, white grubs, wireworms, etc. After mid-July, 200 ml of 50% “phoxim” can be diluted in 50 kg of water and sprayed on the roots, followed by watering, or sprayed before rain. It can also be mixed with an appropriate amount of water and 10-15 kg of fine sand to make poisoned soil, which is spread along the rows before rain or watered after spreading. If underground pests are found, use methyl isofenphos or phoxim promptly for root irrigation. Fungicides and insecticides can be mixed and sprayed together to achieve simultaneous control of pests and diseases.

II. Seedling stage

The common diseases at the peanut seedling stage mainly include stem rot and root rot. They mainly manifest as large-scale seedling death at the seedling stage.

1. You can use 20 grams per mu of 2.5% Celest and 25 grams of Tianda 2116 (special for seed dressing), mix with 350 ml of water, dress the seeds, dry them, and then sow;

2. After the peanuts have fully emerged, spray with 96% hymexazol at 3000 times dilution plus 3% acetamiprid at 1500 times dilution plus Tianda 2116 (seedling strengthener) at 600 times dilution, which basically solves the problem of seedling death at the peanut seedling stage.

III. Yellow leaves

Peanut leaf yellowing mainly manifests in the following three aspects of symptoms:

First, iron deficiency yellowing. It generally manifests as loss of green in the upper young leaves, while the lower old leaves and leaf veins remain green. In severe cases, the leaf veins lose green and then yellow, and all the upper new leaves turn white, develop brown spots, become necrotic, dry up, and fall off; in iron deficiency yellowing, peanut leaf size generally does not change significantly, but the loss of green and yellowing are obvious.

Second, nitrogen deficiency yellowing. Yellowing and loss of green in peanut leaves caused by nitrogen deficiency first appears as fading green in the lower old leaves of the plant. It generally also shows thinner and smaller leaves and stunted plants. Nitrogen deficiency yellowing is generally prone to occur in poor barren land, wheat intercropping, and summer direct-seeded peanuts.

Third, zinc deficiency yellowing. Peanut leaf yellowing caused by zinc deficiency generally manifests as clustered leaves and the appearance of yellow-white small leaf symptoms.

Control of peanut leaf yellowing:

To control iron deficiency yellowing in peanuts, the most commonly used method at present is foliar spraying of ferrous sulfate. Generally, a 0.1%-0.2% ferrous sulfate (commonly known as black alum or green vitriol) solution can be sprayed on the leaves once every 5-7 days, for 3-4 consecutive sprays. To enhance adhesion to the leaf surface, 0.1% neutral washing powder can be added to improve the spraying effect and enhance the absorption function of the leaf surface. Preparations such as Luye Bao, which use iron chelates as the main component and add some trace elements, can also be selected, and their spraying effect is often better than simply spraying ferrous sulfate.

For plots with mixed iron deficiency and zinc deficiency yellowing, iron deficiency and zinc deficiency can be prevented together. Generally, 150 grams of ferrous sulfate and 50 grams of zinc sulfate per mu can be mixed with 60 kg of water and sprayed on the leaves.

To control nitrogen deficiency yellowing, an appropriate amount of nitrogen fertilizer can be applied as topdressing before watering or rainfall. For plots where topdressing is inconvenient, about 1% urea aqueous solution can be sprayed on the leaves, which can effectively alleviate the yellowing symptoms.

IV. Cotton bollworm

Master spraying control from the peak egg-hatching period to the 2nd-instar larval stage, with the best effect achieved by spraying at the peak egg-hatching period.

1. Spray once every 7-10 days, for a total of 2-3 sprays. When spraying, the liquid should mainly be applied to the upper tender leaves, growing tips, and young buds of the cotton plants, and all surrounding areas must be thoroughly covered. Also pay attention to alternating or mixing multiple pesticides to avoid or delay the development of cotton bollworm resistance.

2. In the early growth stage of cotton, focus on controlling the 2nd-3rd generation cotton bollworm in cotton fields. From the peak egg-hatching period to the 2nd-instar larval stage, pesticides with a longer residual period and good ovicidal effect can be used:

Yibaoding (8.2% emamectin benzoate · tebufenozide) 20 ml diluted in 15 kg of water for spraying; 20% chlorpyrifos · phoxim emulsifiable concentrate 100-150 ml/mu; 15% abamectin · triazophos emulsifiable concentrate 60-70 ml/mu; 40% diesel · phoxim emulsifiable concentrate 100-150 ml/mu; 15.5% emamectin benzoate · chlorpyrifos emulsifiable concentrate 75-100 ml/mu; 1.8% abamectin emulsifiable concentrate 10-20 ml/mu; 1% emamectin benzoate emulsifiable concentrate 15-20 ml/mu; 40% trichlorfon · chlorpyrifos emulsifiable concentrate 60-80 ml/mu; 20% triazophos · phoxim emulsifiable concentrate 60-100 ml/mu; 20% malathion · phoxim emulsifiable concentrate 75-90 ml/mu; 50% trichlorfon · phoxim emulsifiable concentrate 50-80 ml/mu; 12% malathion · fenitrothion emulsifiable concentrate 75-100 ml/mu; 40% profenofos emulsifiable concentrate 80-100 ml/mu; 5% hexaflumuron emulsifiable concentrate 120-160 ml/mu; 8000 IU/ml Bacillus thuringiensis wettable powder 200-300 g/mu; 10 billion PIB/g Helicoverpa armigera nuclear polyhedrosis virus wettable powder 80-100 g/mu; 48% chlorpyrifos emulsifiable concentrate 90-125 ml/mu; 40% methyl chlorpyrifos emulsifiable concentrate 100-175 ml/mu; 35% phosalone emulsifiable concentrate 160-180 ml/mu; 25% quinalphos emulsifiable concentrate 60-100 ml/mu; 50% fenthion emulsifiable concentrate 50-100 ml/mu; 40% isocarbophos emulsifiable concentrate 50-100 ml/mu, mixed with 50-60 kg of water for uniform spraying.

3. To control the 3rd-4th generation cotton bollworm in cotton fields, there is generation overlap in this period, and cotton bollworms of various generations occur in the field. Pay attention to applying fast-acting, highly effective insecticides:

30% cypermethrin · phoxim emulsifiable concentrate 60-80 ml/mu; 12% beta-cypermethrin · chlorpyrifos emulsifiable concentrate 100-150 ml/mu; 25% fenpropathrin · phoxim emulsifiable concentrate 80-100 ml/mu; 20% beta-cypermethrin · malathion emulsifiable concentrate 70-100 ml/mu; 20% hexaflumuron · phoxim emulsifiable concentrate 50-75 ml/mu; 25% profenofos · phoxim emulsifiable concentrate 60-80 ml/mu; 25% cyhalothrin · profenofos emulsifiable concentrate 40-80 ml/mu; 15% beta-cypermethrin · triazophos emulsifiable concentrate 50-70 ml/mu; 25% fenvalerate · phoxim emulsifiable concentrate 70-90 ml/mu; 44% cypermethrin · profenofos emulsifiable concentrate 70-100 ml/mu; 52.25% cypermethrin · chlorpyrifos emulsifiable concentrate 80-110 ml/mu; 2.5% beta-cyhalothrin emulsifiable concentrate 40-60 ml/mu; 20% phoxim emulsifiable concentrate 100-125 ml/mu; 4.5% beta-cypermethrin aqueous emulsion 60-80 ml/mu; 20% acephate emulsifiable concentrate 225-300 ml/mu; 5% S—fenvalerate emulsifiable concentrate 40-50 ml/mu; 35% endosulfan emulsifiable concentrate 130-170 ml/mu; 2.5% deltamethrin emulsifiable concentrate 30-50 ml/mu; 2.5% bifenthrin emulsifiable concentrate 110-140 ml/mu; 2.5% cypermethrin emulsifiable concentrate 15-20 ml/mu; 10% alpha-cypermethrin emulsifiable concentrate 15-20 ml/mu; 5% cyhalothrin emulsifiable concentrate 32-50 ml/mu; 1.8% zeta—cypermethrin emulsifiable concentrate 16-22 ml/mu; 20% fenpropathrin emulsifiable concentrate 30-40 ml/mu, mixed with 50-60 kg of water for uniform spraying, thoroughly and evenly.

What pesticides should be used for peanuts to achieve high yield?

To increase peanut income, you first need to control the vigorous growth of peanuts.

During the growth period of peanuts, with sufficient rain, sufficient light, and sufficient nutrients, the peanut vines begin to grow wildly, some reaching waist height. The stems and leaves grow strongly and absorb nutrients from the roots, which affects the pod-setting rate.

1. Combine organic fertilizer with chemical fertilizer

In order to improve the available nutrients in peanut field soil and form a soil structure that is loose on top and firm below with coordinated air and water, organic fertilizer must be combined with chemical fertilizer in terms of fertilizer types.

2. Combine fertilization of the previous crop with fertilization of the current crop

Peanuts have the characteristic of liking residual fertilizer. Most of the nutrient elements needed by high-yield peanuts are absorbed from the original soil. Therefore, in peanut fields with medium or higher fertility, fertilizing the previous crop has a better effect than fertilizing the peanut crop itself, resulting in higher grain yield and abundant peanut yield.

3. Base fertilizer as the main application, topdressing as supplementary

Before the flowering and pegging stage, peanuts have the strongest root fertilizer absorption capacity and the largest fertilizer absorption amount. Therefore, the fertilizer needed by high-yield peanuts should be applied entirely or mostly as base fertilizer and seed fertilizer in combination with winter plowing and early spring plowing.

4. Fertilization ratio for the current peanut crop

According to the absorption amount of the main nutrient elements nitrogen, phosphorus, and potassium by high-yield peanuts and the fertilizer absorption utilization rate, the fertilization ratio of halving nitrogen, doubling phosphorus, and applying the full amount of potassium is adopted. That is, apply 13.5 kg of nitrogen, 11 kg of phosphorus, and 16 kg of potassium per mu.

In medium-fertility fields with relatively low basic soil fertility, to achieve high yield, the fertilization ratio of applying the full amounts of nitrogen and potassium and doubling phosphorus is adopted. That is, apply 27 kg of nitrogen, 11 kg of phosphorus, and 16 kg of potassium per mu.