Detailed Explanation of Key Techniques for High-Yield Bell Pepper Cultivation

The bell pepper belongs to the plant kingdom, class Dicotyledoneae, subclass Asteridae, family Solanaceae. Together with the red chili, it is collectively called pepper. The fruit is a berry. It has many aliases: big pepper, lantern pepper and persimmon pepper are all names for it, and because it can bear sweet berries, it is also called sweet pepper or vegetable pepper. Bell peppers are rich in nutrients and are one of the vegetables people enjoy all year round.

Characteristics

1. The main root of the pepper is not well developed and the root mass is small; the root system is mostly distributed in the 10—15 cm topsoil layer, and it is neither drought-tolerant nor waterlogging-resistant. Its root regeneration capacity is weaker than that of tomato and eggplant. It does not tolerate concentrated fertilizer.

2. Generally, when the main stem grows to 7—15 leaves, a flower bud forms at the stem tip, and growth continues by two-forked or three-forked branching. Generally speaking, even for the same variety, when planted in autumn, the number of leaves at branching is fewer than in spring, usually 8—9 leaves.

3. High temperature and drought induce the occurrence and spread of viral disease, and hot, rainy weather also often brings epidemics of viral disease.

4. Flower drop, fruit drop and leaf drop of peppers (commonly called the “three drops”) also tend to occur easily. This is an important problem in pepper production and greatly affects yield. The causes of the “three drops” are relatively complex. Flower drop in early spring is mainly caused by low temperature affecting pollination and pollen tube elongation; drought in the soil and air is also a cause of flower drop; too much or too little nitrogen fertilizer, excessive vegetative growth and insufficient light directly affect the balance between vegetative growth and reproductive growth, leading to flower drop; high temperature and drought causing viral disease, or high temperature and waterlogging weakening the root absorption capacity, causing physiological disorders in the plant, as well as pests and diseases (anthracnose, ring spot disease, cotton bollworm, noctuid moths) and so on, cause large numbers of the “three drops”.

Requirements for Environmental Conditions

1. Temperature ① Germination stage: from seed sprouting to cotyledons flattening and true leaves emerging. The optimum germination temperature is 25—30℃; below 15℃ germination is difficult; ② Seedling stage: from the appearance of true leaves to the first flower bud. The optimum growth temperature for seedlings is 25—30℃ during the day and 20—25℃ at night, with a soil temperature of 17—22℃; ③ Flowering and fruiting stage: from the first flower bud to the setting of the first fruit is the initial flowering stage; 20—25℃ during the day and 16—20℃ at night are favorable; ④ When the temperature exceeds 40℃, growth almost stops.

2. Light It requires moderate light intensity, around 45,000 lux. Under direct strong light it grows poorly and is prone to sunscald. For generally thermophilic vegetables, the light saturation point for photosynthesis is mostly around 50,000 lux.

3. Water Its water requirement is not very high, but because the root mass is not well developed, it is difficult to obtain high yields without keeping the soil moist regularly. If pepper plants are submerged in water for several hours, the plants will die.

4. Soil It grows well in high, dry terrain with good drainage and fertile, deep soil. Generally sandy soil and clay soil can also be used for cultivation, but it should not be planted on low-lying, waterlogged land. Continuous cropping with Solanaceae crops should be avoided.

5. Fertilizer The growth period is long and the requirements for soil nutrient conditions are strict. Only when planted in soil with above-medium fertility can high yields be achieved. Applying heavy base fertilizer and topdressing early gives obvious results.

Variety Selection

Choose varieties that are heat-tolerant, virus-resistant, vigorous in growth, concentrated in fruiting, large-fruited with thick flesh, and relatively cold-tolerant. Hybrid peppers show extremely obvious heterosis, so the use of hybrid ox-horn peppers is advocated.

Sowing Period and Seed Treatment

(1) Seed soaking and germination

Before sowing, float off the shriveled seeds with clean water, rub and wash the mucus off the seed surface, then remove the seeds and place them in 55-60 degree water, stirring constantly. When the water temperature drops to 30-35 degrees, stop stirring, soak for 5-6 hours, then remove, spread out to dry slightly, and place the seeds at 28-30 degrees to germinate. Wash them once a day, dry them slightly and continue germination. After 3-4 days, when 50%-60% of the seeds have sprouted, they can be sown.

(2) Sowing period

Although the characteristics of bell peppers mean they easily drop flowers above 35℃, choosing to sow from July 10--15 carries little risk, and doing so is beneficial to the vegetative growth of peppers and to increasing yield. From another perspective, bell peppers have the habit of continuous flowering and fruiting; even if the first fruit flower drops, the next fruit follows. From the perspective of average temperature, in the ten days of late August, the first five days and the last five days have historically been 26.9℃ and 26.6℃ respectively, and the historical average temperature in early September is 25.3℃. Bell peppers flower and fruit suitably at 20--25℃. In autumn, mornings and evenings are generally cooler, so analysis of the climate in late August and early September is relatively favorable for the flowering and fruiting of bell peppers.

Cultivating Strong Seedlings

At sowing time, because of high temperature, strong light and frequent typhoons and heavy rain, seedling raising must be carried out in a shaded shed. Direct sowing in nutrient soil blocks or plastic (9865,205.00,2.12%) pots is used for seedling raising. In our opinion, nutrient soil block seedling raising is better; plastic pot seedling raising easily loses water and is accompanied by high temperature. After emergence, supplement water appropriately to prevent drought, but avoid high temperature. Apply appropriate quick-acting fertilizer, generally by splashing with 0.5% imported compound fertilizer solution. Spray with chlorothalonil, carbendazim, or fungicide at 600 times dilution to prevent disease. The leaves should be thick, dark green, with a well-developed root system and no pests or diseases.

Field Management

(1) Transplanting

When the seedlings are 10---15 cm tall and have 6 true leaves, they can be transplanted. Water the seedbed thoroughly the day before transplanting; when transplanting, cut the blocks and transplant with soil, with two seedlings per block. Pepper plants are compact and have great potential for rational close planting. Close planting also helps the plants close the rows early, so that the soil surface is covered and shaded, soil temperature changes little, and the root system is not easily exposed to the sun, thereby achieving root and plant protection and reducing viral disease. Therefore, sparse planting should be changed to rational close planting: the customary 2500-3000 holes per mu can be increased to 4500 holes per mu. In field layout, to facilitate operation and management and better obtain marginal effects (edge plants with more space can increase fruit set and promote high quality), it is advisable to have two rows per bed, with a row spacing of 60 cm and a reduced hole spacing of 25 cm. Intercropping is also beneficial for reducing the occurrence of viral disease and other diseases.

(2) Seedling stage

From the appearance of the first true leaf to the formation of the terminal bud flower bud takes about 50-60 days. During this period the plant grows slowly and is sensitive to low temperature. Within 2-3 days after the first true leaf appears, control water and temperature. When the seedlings grow to 6-7 true leaves, apply a small amount of urea as a seedling-promoting fertilizer to promote stem and leaf growth, and thin the seedlings in time when they are tall. If environmental conditions and management are reasonable, strong seedlings with well-developed roots, thick short stems and green leaves can be cultivated, laying a good foundation for the flowering, fruiting and yield formation of bell peppers.

(3) Water management

Bell peppers have different water requirements at each growth stage. Seed germination needs to absorb a certain amount of water, so seeds must be soaked for germination; seedlings are small and have different water needs, and moist soil is enough; after transplanting, the plants are larger and the water requirement increases; during the fruit expansion stage, if water is insufficient, the fruit surface will shrivel, bend, and lose color, reducing yield and quality. Therefore, supplying enough water during this period is an important measure for obtaining high yields.

(4) Topdressing

After the first fruit has set, apply one topdressing together with watering, applying 15 kg of urea per mu. Entering the full fruiting stage, apply topdressing about once every 20 days together with watering, each time applying 15-20 kg of diammonium phosphate and 10 kg of potassium sulfate per mu. Combined with spraying, 0.2% potassium dihydrogen phosphate can be used for foliar topdressing.

(5) Pruning

After the first fruit has set, remove all side branches below the first fruit. In the late fruiting stage, remove the old leaves, yellow leaves and diseased leaves at the bottom of the plant, and remove ineffective branches.

5. Pest and Disease Control

For pest and disease control, promptly control viral disease, anthracnose and phytophthora blight occurring during the growth period of bell peppers. Spray with 70% thiophanate-methyl wettable powder at 500-600 times dilution, or 64% oxadixyl M8SK wettable powder at 400-500 times dilution, or 70% mancozeb wettable powder at 400 times dilution, once every 7-10 days, with very good results. To control aphids, use 40% dimethoate emulsifiable concentrate at 1500 times dilution. Combined with spraying, spray potassium dihydrogen phosphate on the leaves.