How should aphids on peanuts be controlled?

Peanuts are eaten quite a lot in our daily lives. We all know that peanuts have many benefits: eaten raw, they can help nourish the blood, and they can also be pressed into peanut oil, which is also very good. Therefore, peanuts have many uses.

How to control aphids when growing peanuts

The peanut aphid is an important pest that harms peanuts. Damage is most severe at the early flowering stage of peanuts. Peanut aphids mostly gather on the stems, leaves and flowers at the top to cause damage. Affected plants have curled leaves and slow growth, which affects flowering and pod setting. 

In my area, after peanut seedlings emerge, peanut aphids migrate from alternate hosts such as weeds and thorny plants into peanut fields. In early to mid-June, they occur in scattered patches, and afterward spread to the whole field to cause damage. This period coincides with the peanut flowering stage. If the weather is dry and temperatures are high, the aphid population density surges and the damage worsens. This period is the key time for control. 

Control methods 

1. Spray 2 kg per mu of 1% dimethoate powder or 1.5% pirimicarb. 

2. Spray with a 2000-fold solution of 2.5% deltamethrin emulsion or a 4000-fold solution of 5% pirimicarb, or spray with a 1000-fold solution of 40% dimethoate emulsion.

Fertilization management for growing peanuts  

First, apply a light seedling fertilizer. Fertilizer for peanut seedlings can promote early development, strong seedlings and more branches, increasing the number of flowers and pods and raising yield. The nutrient requirement at the seedling stage is relatively small, but where base fertilizer is insufficient or no base fertilizer was applied, quick-acting nitrogen fertilizer should be applied appropriately to promote seedling growth and flower bud differentiation. You can directly apply 3-4 kg of urea per mu before flowering, or 250-300 kg of decomposed human and livestock manure urine water fertilizer, mixed with increased phosphorus and potassium fertilizer, and sprinkle it on;  

Second, apply a flowering and pegging fertilizer. The pegging stage requires more fertilizer, and its role is to promote more flowering, more pegs and more pods in peanuts. Generally, apply 4-5 kg of urea, 6-7 kg of diammonium phosphate, and 5-6 kg of potassium sulfate per mu, or 50-75 kg of plant ash. If the plants are weak during the pegging and pod-setting stage, 100-250 g of urea can also be added when carrying out foliar topdressing and sprayed together;  

Third, apply a pod-setting fertilizer skillfully. The pod-setting stage is the period of greatest fertilizer demand, and also the key period for promoting dry matter accumulation and the development of pegs and pods. Before the rows close, apply 4-5 kg of diammonium phosphate and 6-8 kg of superphosphate per mu. For those that have not been given boron or zinc fertilizer, 0.1%-0.2% zinc sulfate or borax aqueous solution can be sprayed 2-3 times when the pod-setting fertilizer is applied. In the late growth stage of peanuts, because the plants have already closed rows, it is not suitable to apply topdressing fertilizer, but for those showing signs of fertilizer deficiency, a 1%-2% urea solution can be used for foliar spraying to increase the seed-setting rate and strengthen the pods. 

Key management techniques for high-yield peanuts  

1. Release seedlings, replant and clear branches in time. For plastic-film-mulched peanuts, when the seedlings crack the soil mound and show green, remove the soil (mound) above the sowing row to the furrow, exposing the cotyledon node. Starting from the rosette stage (when the main stem has 4 compound leaves), check in time and pick out the lateral branches growing horizontally that are pressed under the film so that they grow robustly. This needs to be done 2-3 times before the beginning of flowering.  

2. Drain and irrigate in time, prevent drought and prevent waterlogging. For spring and summer peanuts sown with sufficient soil moisture, watering is generally not needed at the seedling stage. Appropriate drought is beneficial to root development and improves the plant's ability to resist drought and tolerate waterlogging. For wheat-intercropped peanuts, if drought occurs at the seedling stage, water in time to protect the seedlings.  

The middle growth period (pegging stage and pod-setting stage) is the period when peanuts are most sensitive to water response and also the period of greatest water demand in their whole life. When plant leaves wilt around noon, water in time. In the late growth period (full pod stage), if drought occurs, water promptly with a small amount of light irrigation and moistening irrigation to prevent premature aging of plants and contamination of pods by aflatoxin. In addition, peanut fields should have three ditches flowing freely, with no waterlogging damage.  

3. Cultivate, topdress and weed in a timely manner. For wheat-intercropped peanuts, after wheat harvest, cultivate in time to destroy stubble and weed. For plots that need topdressing, open a furrow on one side of the peanut plants, apply the fertilizer, then cover with soil and water, and carry out intertillage at suitable soil moisture. When the peanuts in the field are close to closing rows, dig a furrow between two rows of peanuts and earth up. Earthing up should be done so that the furrow is clean, the soil is loose, the ridge waist is plump and the ridge top is concave, so that more pegs enter the soil and set pods.  

4. Prevent diseases and control insects in time. When the rate of diseased peanut leaves reaches 10%, promptly spray the leaf surface alternately with fungicides such as 60% Bai Tai wettable powder 1500-fold solution, 70% thiophanate-methyl wettable powder 500-fold solution, and 43% tebuconazole 1500-fold solution, spraying 2-3 times continuously at 10-15 day intervals, to control leaf spot disease, net blotch and so on.  

How to control empty-shell peanuts  

1. Apply more organic fertilizer. Because organic fertilizer has comprehensive nutrients, generally apply 3000-4000 kg of decomposed organic fertilizer per mu as base fertilizer. If the amount of base fertilizer is large, it can be applied throughout the plow layer; if the amount is small, it can be applied as seed fertilizer.  

2. Apply superphosphate. Because superphosphate not only contains phosphorus but also contains a large amount of gypsum, and gypsum is also called calcium sulfate, it can add calcium fertilizer to the soil. Generally apply 30-40 kg of superphosphate per mu as base fertilizer.  

3. Spray boron fertilizer. Boron is a nutrient element necessary for the normal development of plant flowers and reproductive organs. In sandy soil and soil with severe boron deficiency, apply 1 kg of borax per mu as base fertilizer or seed fertilizer. For general soil, 0.2%-0.3% borax solution can be used for foliar topdressing 2-3 times at the early flowering stage.  

① Spray molybdenum fertilizer. Molybdenum fertilizer can promote well-developed peanut root nodules, dark green leaves, robust growth and full, plump pods. At the early flowering stage or the pegging and pod-setting stage, use 0.3%-0.5% ammonium molybdate solution per mu for foliar topdressing.  

② Apply potassium fertilizer deeply. Potassium fertilizer should be applied deeply below the pod-bearing layer to prevent the pod-bearing layer from containing too much potassium, which affects calcium absorption and increases rotten pods.  

4. If peanut seedlings are weak and leaves are pale, you can add 0.3% urea and 0.3% potassium dihydrogen phosphate solution, once every 7-10 days, spraying continuously 2-3 times. This can reduce the empty-shell rate of peanuts and increase the seed-setting rate, and generally can increase yield by more than 10%.

It can thus be seen that in the process of growing peanuts, disease prevention and treatment are very important, and are also an important method for increasing yield. The next point is the handling technique for empty-shell peanuts, which also directly affects peanut yield.