Rice planting requires well-known knowledge

First, emergence barrier

1, no emergence

By the time specified, the seeds are still not topping out. The cause is related to seed quality, seed treatment, and nursery environment. If the seed has been rotted and germinated , it should be reseeded; when the substrate is too dry, the warm water should be replenished; when the substrate is too wet, the seedling tray should be moved out of the germination chamber, or the seedbed (sow bed) should be uncovered in the sunlight. Dry the sun and continue to germination after the humidity is lowered.

2, the emergence is not neat

The time and density of emergence after seeding are inconsistent. Therefore, there are two situations in which the emergence of seedlings is not uniform: one is that the emergence time is inconsistent; the other is that the seedlings in the seedbed are unevenly distributed. The main reasons for the former: First, poor seed quality, inconsistent maturity or new seeds

Chen seeds are mixed; second, the seedbed environment is uneven, and the difference between the parts is too large; the third is that the seeding depth is inconsistent. The main reason for the latter is caused by poor seeding techniques and poor management of the seedbed, such as uneven seeding, localized rotten seeds or damaged seed buds. Precautionary measures: seeding high quality seeds; fine soil preparation, uniform sowing, improve seeding quality; maintain uniform seedbed environment; strengthen seedling pest control.

3, cotyledons "wearing caps" unearthed

After the seedlings are unearthed, the seed coat does not fall off and the cotyledons are clamped. The main causes are over-thickness of the soil, drying of the cover soil, improper seeding methods, and weak seed viability. Precautionary measures: First, it is necessary to plant enough seeds; second, new seeds with high maturity should be selected, and should be kept safely to avoid dampness; third, evenly cover the soil after sowing, when the seeds are sowed, the seeds should be placed flat on the substrate; The vegetable cover soil thickness is 0.5 cm, and the melon vegetable is 1 cm; after covering the soil, the topsoil is sprayed with water spray to moisten the topsoil to prevent the cotyledons from wearing caps. If there are still cotyledons wearing caps, it is necessary to cover the moist fine soil in time to help the cotyledons unshell. For a small number of cotyledon caps, the seed coat can be manually picked. The sowing depth should be suitable, and the film or grass should be moisturized after the high temperature period.

Second, seedling roots and rooting

1, root

When the roots are rooted, the roots are rusted. In severe cases, the epidermis rots, the new roots do not grow, and the seedlings turn yellow and wilted. The main reason is that the seedbed has excessive humidity for a long time and the soil is poorly ventilated. Precautions: Improve seedling conditions and avoid excessive humidity in the soil for a long time.

2, burning roots

When rooting, the root tip is yellow, no new roots are produced, but the roots are not bad. The growth of the shoots is slow, short and hard, and no hair is formed, forming a small old seedling. The main reason for root burning is excessive fertilization or the use of unfertilized organic fertilizer. Precautionary measures: When the seedling soil is prepared, the unfertilized organic fertilizer is not used, and the chemical fertilizer is not used excessively and is evenly mixed with the bed soil.

When raising seedlings, it should be planted in time; 50%~60% of the seedlings are unearthed, and timely light greening; proper ventilation, control of appropriate temperature and humidity; anti-freezing insulation of seedlings; prevention and treatment of diseases. In short, the suitable growth environment for the seedlings should be arched.

(Original title: Analysis of the causes of common problems in rice seedlings and preventive measures)