Control techniques of pea diseases and insect pests

Pea is the fourth largest legume crop in the world. China is the second largest pea producer in the world after Canada and plays an important role in pea production in the world. Pea diseases are mainly root rot, brown spot, powdery mildew, brown streak and so on. The main pests are black miner, leaf miner and so on. Let's take a look at the pest control techniques of pea.

Pea root rot

[symptoms] the disease can occur from seedling to adult plant, mainly at the root or stem base, and the leaves of the diseased plant first yellowed, then gradually developed to the middle and upper parts, resulting in the yellowing and wilting of the whole plant. The main and lateral roots turned dark brown or soil red, root nodules and root hairs decreased obviously, while light ones caused plant dwarfing, thin stems, wilting or wilting of leaf branches.

[cause] the pathogen spreads through soil, diseased tissue and seeds, and invades through seed coat and lateral root, which is easy to be confused with Fusarium wilt. The disease is usually serious in dry years.

[agricultural control] select disease-resistant varieties, such as Gansu Gongjingxuan, sesame pea, adzuki bean 60, adzuki bean 704 and so on.

[medicament seed dressing] seed dressing with 20% triadimefon EC with 0.25% seed weight, or seed dressing with 75% chlorothalonil wettable powder with 0.2% seed weight has a certain effect.

Pea brown spot

The main symptoms are damage to leaves, stems and pods. The infected leaves showed irregular lavender dots. Under the condition of high temperature and high humidity, the disease spots spread rapidly and covered the whole leaves. After that, the diseased leaves yellowed and twisted and withered, some showed dark brown irregular ring spots, and black spots were produced in the central necrotic place. The pathogenic bacteria mainly overwintered on the seeds and spread by wind and rain. Sowing too early or suffering from low temperature and cold injury, or soil viscosity and humidity is too high, or partial application of nitrogen fertilizer, plant growth, are easy to occur.

[agricultural control] seriously diseased fields and non-leguminous vegetables should be rotated for 2-3 years, and seeds should be disinfected at the same time. After pre-soaking in cold water for 4-5 hours, soaking in 50 ℃ warm water for 5 minutes, then cooling, drying and sowing. Appropriate close planting, increase the application of potash fertilizer.

[pharmaceutical control] at the initial stage of the disease, 50% carbendazim wettable powder suspension 800 times solution, 70% methyl thiophanate wettable powder 500 times solution, 75% chlorothalonil wettable powder 600 times solution, once every 7 days, 2-3 times in succession.

Pea powdery mildew

[symptoms] at the initial stage of the disease, the leaves were small yellowish spots, which expanded into irregular powder spots. In severe cases, the leaves were covered with a layer of white powder on both sides, and finally turned yellow and died. In the later stage of the disease, the pink spot turned gray and grew into many small black particles.

[prevention and treatment methods] at the initial stage of the disease, spray prevention and control was carried out with 25% fenuoning wettable powder 2000-3000 times, or 70% methyl thiophanate wettable powder 1000 times, or 50% carbendazim wettable powder, or Baume 0.2-0.3 degree stone sulfur mixture and so on. Spray once every 10 to 20 days, 2 times in a row.

Brown streak of pea

The main symptoms are damage to leaves, stems and pods. The infected leaves showed irregular lavender dots. Under the condition of high temperature and high humidity, the disease spots spread rapidly and covered the whole leaves. After that, the diseased leaves yellowed and twisted and withered, some showed dark brown irregular ring spots, and black spots were produced in the central necrotic place. The pathogenic bacteria mainly overwintered on the seeds and spread by wind and rain. Sowing too early or suffering from low temperature and cold injury, or soil viscosity and humidity is too high, or partial application of nitrogen fertilizer, plant growth, are easy to occur.

[agricultural control] it is best to rotate with non-legume crops for more than 3 years, and disinfect seeds, soak seeds in warm water for 4-5 hours, then soak seeds in 55 ℃ warm water for 5 minutes, cool in cold water, dry and sow seeds. Appropriate close planting, increase the application of potash fertilizer.

[pharmaceutical control] at the initial stage of the disease, 50% mixed sulfur suspension was sprayed 500 times, or 75% chlorothalonil wettable powder 600 times, once every 7 days, 2-3 times continuously.

Liriomyza sinensis

[harmful symptoms] Liriomyza huidobrensis is a pest of the genus Liriomyza huidobrensis of the family Liriomyidae, which is widely distributed, mainly harming leguminous crops, from the young parts of the veins and petioles of the newly hatched larvae into the main stem, pulp and xylem. If the prevention and control is not timely, it will result in a serious reduction in production.

[agricultural control] properly adjust the sowing date and stagger the peak spawning period of adults in order to reduce the damage.

[chemical control] the application of 40% dimethoate, or 40% omethoate, or 50% fenitrothion, or 45% phoxim EC requires 1000 times of water and 75 kg per mu.

Pea leaf miner

[harmful symptoms] Pea leafminer is a polyphagous pest with more than 130 host plants, which is mainly harmful to pea, broad bean, chrysanthemum, celery, cabbage, radish and cabbage.

[agricultural control] after vegetables are harvested, the fallen leaves and weeds of the residual plants in the field should be removed in time, burned or retted, so as to reduce the number of insect population in the field.

[chemical control] choose agents with short residual effect, easy photolysis and hydrolysis. In addition, due to the damage caused by the latent leaves of the larvae, it is necessary to seize the critical moment from the peak spawning period to the initial stage of hatching. Kill (21% synergistic cypermethrin EC) 800x, 2.5% deltamethrin or 20% fenvalerate 2500 times, 10% bromo horse EC 2000 times, 10% chrysanthemum horse EC 1500 times, 1.8% acaroid and 1.8% fenvalerate 3000-4000 times spray. In the appropriate period of control, spraying can get a better control effect.

Integrated control of pea diseases

1. Select disease-resistant varieties: in general, peas with small pods are more resistant than peas with large pods.

2. Rotation: continuous cropping is avoided because pea root exudates have an effect on plant nodule activity and root growth in the following year. Rotation can be carried out with non-leguminous crops such as melons and fruits or gramineous food crops.

3. Seed disinfection: seeds can be mixed with 0.3% methyl thiophanate, or 50% carbendazim wettable powder plus 75% chlorothalonil wettable powder (1 ∶ 1), and sealed for 48 hours before sowing.

4. Strengthen field management: reasonable fertilization and close planting, avoid planting in low wetlands, and adopt high border or ridging cultivation. To increase the application of phosphorus and potassium fertilizer and avoid partial application of nitrogen fertilizer, brassin can be sprayed regularly to improve disease resistance.

5. do a good job in field hygiene: timely pull out diseased plants and pest-damaged plants, as well as straw and stubble after harvest, and concentrate on deep burial or burning, so as to reduce the sources of disease and insects.

6. Chemical methods: the prevention and control of Liriomyza huidobrensis should focus on pea seedling stage. 1.8% acaridin EC (avermectin) 2000 times solution or 50% phoxim EC 1000 times solution or 48% Lesben EC 1000 times solution can be used for root irrigation or spray control.