Field management refers to comprehensive management from sowing to harvest, aiming to create optimal growing conditions and maximize crop productivity. Here are some key scientific points for key measures:
1. Checking and Replenishing Seedlings
Checking and replenishing seedlings is fundamental to high yields. After sowing, seedling gaps often occur due to factors such as seed quality, sowing techniques, and moisture. After emergence, seedlings should be checked promptly. If there are many gaps, replant with the same variety of seeds and apply fertilizer to promote growth. If there are only a few gaps, transplant seedlings. Cereal crops should be transplanted before the three-leaf stage, and dicotyledonous crops before the first pair of true leaves, with soil attached. Transplanting should be done on cloudy days or in the evening, and watered after transplanting to ensure survival.
2. Thinning and Fixing Seedlings
Thinning and fixing seedlings ensures a reasonable density. Since the sowing rate is usually much higher than the final density, seedlings become crowded after emergence. Thinning should be done in stages, following the principles of removing dense seedlings and keeping evenly spaced seedlings, removing weak seedlings and keeping strong seedlings, removing diseased seedlings and keeping healthy seedlings, and removing mixed seedlings and keeping pure seedlings, avoiding damage to neighboring plants. Thinning is the final stage of thinning, ensuring even spacing between plants and rows, and promptly replanting where rows are broken.
3. Cultivation and Hilling
Cultivation and hilling improve soil conditions. They loosen the soil, remove weeds, reduce water evaporation during droughts, and dissipate moisture and raise the temperature during waterlogging. Generally, this is done 2-3 times, to a depth of 6-8 cm. Hilling also stabilizes stems, promotes root growth, prevents lodging, and for overwintering crops, it protects against frost damage.
4. Fertilization
Follow the principle of using primarily organic fertilizer, combined with inorganic fertilizers, and a balanced use of nitrogen, phosphorus, and potassium, supplementing with micronutrients if needed. There are three methods: base fertilizer (applied before sowing, accounting for 50%-80% of the total, mainly organic fertilizer and phosphorus and potassium fertilizers), seed fertilizer (applied near the seeds at sowing, mainly nitrogen and phosphorus or well-rotted organic fertilizer, with strict control of dosage; urea is not suitable as seed fertilizer), and topdressing (applied during the growing season, mainly nitrogen fertilizer, applied during critical nutrient periods or periods of maximum efficiency, and can be combined with foliar spraying).
5. Irrigation and Drainage
Irrigation and drainage need to be controlled as needed. Irrigation meets crop water requirements and regulates soil temperature and humidity, and is divided into four categories: surface irrigation, subsurface irrigation, sprinkler irrigation, and drip irrigation. Drainage removes excess water and lowers the groundwater level, using both open and covered ditches, balancing drainage effectiveness with ease of field management.
6. Pest and Disease Control
Adhere to the principle of "prevention first, integrated management," using agricultural, biological, and physical/chemical control methods to control pests and diseases. Weed control can be achieved through comprehensive measures such as seed selection, crop rotation, and inter-row cultivation, or by using chemical herbicides for soil and foliar treatment.
