A tutorial on the latest efficient Seedling-raising techniques and methods of vegetables

Vegetable seedling raising is a major feature of vegetable production, and it is an important measure to strive for farming season, increase stubble, give full play to capacity, mature earlier, prolong supply, reduce diseases and insect pests and natural disasters, and increase yield. Raising seedlings can also save seeds and facilitate centralized management and cultivation of strong seedlings. Seedling raising is usually carried out in advance of sowing or planting in the field, or in severe winter and early spring in several cold days, or in hot and rainy summer and early autumn. That is, in the period when the climatic conditions are not suitable for the growth of vegetables, protective facilities should be used to create a suitable environment to cultivate strong seedlings of the right age. Once the climatic conditions are suitable for planting in the field.

Types of nursery beds

1. Cold bed: cold bed, also known as sunny bed, is a protective facility heated by sunlight. It consists of a border frame, a glass cover (or film) and a straw curtain. The bed site of the cold bed should be dug in the place of leeward to the sun, high dryness, good drainage, close to the water source, convenient transportation, close to the vegetable field, close to the dormitory and convenient management, and the orientation of the cold bed should be 15 °north to the south and slightly west to the west, in order to increase the light and raise the bed temperature. The bed frame structure can be made of cement and red brick or mud grass, but the former is durable, does not need annual maintenance, and is more convenient to use. Generally, the north frame is high 50cm and the south frame is high 15cm. The glass window can not only be daylighting, but also heat preservation. Grass curtains are generally covered on the glass windows in the cold night to enhance the insulation effect. The glass window can also be replaced with agricultural film, but the nursing work should be strengthened in rainy or snowy days to ensure smooth drainage and timely snow cleaning.

2. Plastic arch shed: the plastic arch shed is made of bamboo pieces and covered with plastic film. The scaffolding is 50cm high and covered with a 2m wide film. The film is compacted with soil on one side to facilitate heat preservation and wind protection; the other side is pressed with bricks so that the film can be opened at any time and ventilated. Small arched sheds are often used in early spring to sow seeds of melons and beans or to put nutrition bowls for eggplant fruits and melon seedlings. It can also be used as a false planting bed. The small arch shed is generally 1 m and 2 m wide and 20 m 30 m long.

3. Plastic greenhouse: the plastic greenhouse is made of bamboo and wood, reinforced concrete sheet or steel pipe to make arched skeleton material, which is covered with plastic film. At present, plastic greenhouses with length 30cm, 6m wide or 20m long and 4m wide are mostly used in the provinces of the Yangtze River basin. The plastic greenhouse is mainly used for raising eggplant fruit seedlings in winter (figure 1-2). A small plastic arch shed is set up in the greenhouse, and an electric hotline is laid in the small arch shed to raise seedlings of chili, eggplant and tomato. As a seedling raising facility, the plastic greenhouse is more convenient and effective than cold bed, hotbed and plastic arch shed.

Preparation of nursery bed culture soil

The main results are as follows: 1. The conditions that the culture soil should have: the bed soil used for raising vegetable seedlings is also called culture soil. The quality of the culture soil is closely related to the growth and development of the seedlings. in order to cultivate strong seedlings, the culture soil should be fertile, loose, slightly acidic or neutral, good water retention and drainage, free of germs, insect eggs and weed seeds. In order to make the cultured soil have the above excellent properties, it must go through the process of scientific preparation, composting fermentation, chemical disinfection and so on.

2, the proportion of culture soil and raw material preparation: garden soil is the main component of culture soil, which should account for 30%. When selecting garden soil, we should pay attention to prevent soil-borne diseases such as sudden fall and blight, early blight and continuous blight of Solanaceae, Fusarium wilt and anthracnose of melons, and generally do not use garden soil of vegetables of the same family. The soil that has cultivated eggplant fruits and melons is not suitable, and the soil that has planted legumes, onions and garlic vegetables is better. Because there are rhizobia in legume vegetable fields, which has a certain effect of nitrogen fixation, which can increase soil fertility; onion and garlic vegetable fields contain a large number of allicin and other sulfides, which is helpful to inhibit or kill bacteria in the soil. If the above garden soil is indeed difficult, we must eradicate the topsoil and dig up the inner soil. The garden soil had better be dug at high temperature in August. After fully baking, the garden soil should be broken and screened. The sifted garden soil should be stored indoors or covered with thin film to keep dry. Organic fertilizers, such as human and animal feces and urine, other manure or stable manure, edible mushroom scraps, garbage, etc., are the main sources of nutrition, and their content should account for 20% of the cultured soil. These organic fertilizers should be fully fermented before they can be used. The unrotten organic fertilizer absorbs more bacteria and is easy to damage the seedlings. Therefore, pig dung or other barnyard manure must be piled up before it can be used. Or mix it with garden soil and use it after it is completely rotten. Chemical fertilizer, urea 1kg, potassium chloride 0, 5kg, calcium superphosphate or calcium magnesium phosphate fertilizer 2kg were added to the 1000kg culture soil, respectively. Carbonized grain husk or plant ash can increase potassium, make the soil loose, breathable, darker, absorb more solar heat and increase soil temperature, and its content can account for 20% and 30% of the cultured soil. The appropriate degree of grain husk carbonization should be mastered, generally speaking, the grain husk should be completely carbonized, but it is still good to keep the original shape. If there is a lack of grain husk, it can also be replaced by waste cottonseed scraps after planting edible fungi and fermented together with garden soil and barnyard manure.

3. Compost fermentation of cultured soil: after the raw materials are ready, compost fermentation should be carried out 40-50 days before sowing and breeding. Generally, the heap culture soil on the flat ground with high dryness, good drainage and close to the seedling site is selected, and the pile width is 1 to 1.5m. The pile length depends on the amount of culture soil, and the pile is long trapezoid. Specific practice: first lay a layer of 20cm thick garden soil on the ground, then pour through with dung water, and then spread a layer of 10~13cm thick barnyard manure and other soil manure, and sprinkle a layer of dung water. In the future, we will continue to heighten the fertilizer pile according to the above order, generally up to 1 or 5 m high, and then cover with plastic film to protect against rain.

Setting of electric heating hotbed

1. The performance and model of the electrothermal heating line: the electrothermal hotbed mainly depends on the electrothermal heating line to improve the nursery bed temperature, and the electrothermal heating line is essentially a kind of electrothermal conversion device, which is a special wire with certain resistivity. It is covered with ethylene resin with strong heat resistance as an insulating layer, which is buried in a certain depth of soil. After electrification, the current passes through the conductor with high resistance to produce a certain amount of heat, which converts the electric energy into heat energy, thus raising the soil temperature. The heat emitted by electrothermal heating is transferred horizontally layer by layer, the transfer distance can reach about 25cm, and the heat in 15cm is the most. The higher the soil temperature close to the electrothermal heating line is, the lower the soil temperature is. Therefore, in order to make the heat distribution in the seedbed soil uniform, the distance between lines should not exceed 30cm.

2. The procedure of laying the electric hotbed

The bottom of the ① flat bed is in the PS- 4 greenhouse. The bed is made according to the standard of 10m or 20m in length and 1m in width. The excess soil in the bed is shoveled out and the bed bottom is leveled.

② lay heat insulation layer at the bottom of the bed with 5cm thick heat insulation layer, and rake flat.

Several small bamboo sticks are prepared before the wiring of the ③ hotline, and the small bamboo sticks are inserted directly into the two ends of the seedbed according to the wiring spacing, and then three people are used to wire, and the two people pull the wire at both ends and tighten it one by one. Before wiring, it must be considered that the two leads of the electrothermal heating wire are at the same end of the seedling bed in order to connect the power supply. (10 × 1) m2 nursery bed uses 1 DV20810 electrothermal heating wire, which just goes back and forth; (20 × 1) m2 nursery bed needs 2 DV20012 electrothermal heating wires, which just go back and forth, which can ensure that the lead lines are all at the same end of the seedling bed. Attention should be paid to: first, the wires and wires can not overlap or cross, let alone kink, in case of burning out when electrified. Second, the hot line can not be lengthened or shortened at will, because its resistance and power are rated, otherwise it will cause burnout. When the third 2 or more electric heating wires are laid in the same bed, they can only be used in parallel, not in series.

After the ④ test line is laid, turn on the power supply, close the knife switch and power on 1~2min. If the hot line becomes soft and hot, it can cover the bed if the hot line is not heated and the line is blocked. Check the line and troubleshoot it.

After the electrification test of ⑤ covered bed soil, the electric hot wire should be covered with 8~10cm thick bed soil, that is, 100~125kg bed soil per m2. When covering the soil, we should pay attention to pressing the electric hot wire with part of the bed soil in order to avoid displacement when filling the soil, and at the same time, the bed soil should be laid along the direction of the extension of the electric hot wire. After the bed is covered with soil, the surface of the bed is scraped flat with a board in order to sow seeds.