Rice Cultivation Requires Familiar Knowledge

First, emergence obstacles

1.No emergence
By the specified time, the seeds still do not emerge. The reasons are related to seed quality, seed treatment, and nursery environment. If the seeds are rotten and scorched, they should be re-seeded; when the substrate is too dry, warm water should be replenished; when the substrate is too wet, the seedling tray should be taken out of the germination room, or the cover of the seed bed (seeding bed) should be opened and exposed to sunlight Dry in the air and continue to promote germination after the humidity has decreased.

2. Uneven emergence
The phenomenon of inconsistent time and density after sowing. Therefore, there are two cases of uneven emergence: one is that the emergence time is not consistent; the other is that the seedlings are unevenly distributed in the seedbed. The main reasons for the former are: first, poor seed quality, inconsistent maturity or mixed new seeds and old seeds; second, uneven seedbed environment, and local differences are too large; third, inconsistent planting depth. The main reasons for the latter are caused by poor seeding technology and poor management of seedbeds, such as uneven seeding, partial rotten seeds or injured seed buds. Preventive measures: sowing high-quality seeds; fine land preparation, even sowing, improving the quality of sowing; maintaining a uniform and consistent seedbed environment; strengthening prevention and control of plant diseases and insect pests.

3. The cotyledon was "uncovered"
After the seedlings were unearthed, the seed coat did not fall off and pinched the cotyledons. The main reasons are too thin soil cover, dry soil cover, improper planting methods, and weak seed viability. Preventive measures: one is to plant enough sown; the other is to choose new seeds with high maturity, keep them properly to avoid moisture; the third is to cover the soil evenly after sowing. When sowing vegetables, the seeds should be flat on the substrate; The thickness of soil covering vegetables is 0.5 cm, and the thickness of melons is 1 cm. After covering the soil, use a watering can to spray water to moisten the topsoil to prevent the cotyledons from wearing seedlings. If there are still cotyledons with a cap to emerge, cover the wet fine soil in time to help the cotyledons husk. For a small number of cotyledon-hatted seedlings, the seed shells can be removed manually. The seeding depth should be appropriate, and cover film or grass moisturizing after sowing at high temperature.

Second, seedlings roots and burned roots

1, root Roots rust when the roots are rotten, and the epidermis rots when they are severe. They do not grow new roots, and the seedlings become wilting. The main reason is that the long-term humidity of the seedbed is too large, and the soil is not well ventilated. Preventive measures: Improve the nursery conditions and avoid excessive soil humidity for a long time.

2.Root burning
When burning roots, the root tips are yellow and no new roots are produced, but the roots are not rotten. The above-ground growth is slow, short and stiff, and does not grow, forming small old seedlings. The main reasons for root burning are excessive fertilization or use of unripe organic fertilizer. Preventive measures: Do not use undecomposed organic fertilizer when preparing seedling soil. Do not use excessive amounts of chemical fertilizers and stir well with the bed soil.

When seedlings are raised, they should be sown in a timely manner; 50% to 60% of the seedlings should be exposed to light and green in time after being unearthed; appropriate ventilation should be used to control the appropriate temperature and humidity; antifreeze and heat preservation of seedlings; In short, a suitable growth environment should be provided for the seedlings.