How to grow direct-seeded rice? Experience shared by Jingtoushan Farm

Our farm has nearly 700 hectares of paddy fields. We began direct seeding of rice in 1987 and fully promoted it starting in 1999, with a 100% success rate. The key points of this direct seeding technique are mastering the following three critical stages.

First, the land preparation stage. Plow the paddy field, break up the soil, and irrigate; either machine leveling or oxen leveling will do. Then use a leveling bar to smooth the field flat. Use a homemade ditching board to open the furrows. The ditching board is 2 m long, 45 cm wide, and 3 cm thick. On the wooden board, nail 2 handles on each side, each 30 cm long, with a width of 1.6 m between the handles, for attaching ox harness ropes during work. On the bottom center of the wooden board, nail or rivet firmly a piece of wood shaped like a "V", with a top diameter of 20 cm, a tail-end diameter of 8 cm, and a thickness of 15 cm, with the larger end facing forward. During operation, a person stands on the board surface and drives the ox to open furrows across the entire field in a "WV" shape in a clockwise direction, with each bed 2 m to 4 m wide. Finally, go around the edge of the field once. After furrowing the field is completed, use a hoe or shovel to clear the head of each bed furrow, drain the field water, and set aside for use. For farmers without an ox, a 10 kg iron cylinder (sleeve) can be used, 25 cm long, with a solid front end to prevent mud from entering; tie it with a rope and drag it by manpower along the footprints in straight lines to divide beds and open furrows.

Second, the direct seeding stage. For direct-seeded rice in our area, most are middle-season rice varieties; early rice is not suitable for direct seeding because temperatures are unstable. For middle- and late-season hybrid rice varieties, use 2 kg of seed per 667 sq m of field, and it must not exceed 2.25 kg. For conventional rice varieties, use 5 kg to 6 kg per 667 sq m. According to the seeding rate standard, put the rice seed into woven bags and soak in a pond for 30 hours. After taking them out, wash the seed grain, remove empty grains and impurities, and pre-germinate. The rice seed can be direct-seeded once it has broken through the hull and the sprout shows 2 mm.

When direct seeding, the operator carries the rice seed in a bamboo basket or small bucket, works in runs of 3 beds, walks along the surface of the middle bed, and broadcasts while walking. When broadcasting, look straight ahead, grab a handful of rice seed with the right hand, and toss it forward and upward while walking; it must be tossed high so it falls evenly. If thunderstorm weather occurs during broadcasting, wait until the rain stops before broadcasting; when the wind is strong, the grain falls unevenly onto the mud, which increases the labor intensity of replanting seedlings. If heavy rain falls the day after broadcasting, close the field's water outlet, and drain off surface water and accumulated water promptly after the rain stops. During land preparation, if the mud is too thin and pasty, let it stand overnight and broadcast only the next morning to prevent the grain from sinking too deep into the mud and failing to emerge.

Third, the weed control stage. When the seedlings have one leaf and one heart after direct seeding, apply the first pre-emergence herbicide. Method: butachlor 50 g per 667 sq m; after application, keep the field exposed. When the seedlings have two leaves and one heart, carry out the second weeding and spraying, using butachlor 100 g per 667 sq m, plus direct-seeding herbicides such as Shabaikuai or Zhiboxing or Shenchu at 30 g/packet per 667 sq m. If there are broadleaf weeds such as smartweed in the field, also use 2 packets of Kecaoshen per 667 sq m, plus 200 g of rice insecticide, and spray. After 1 to 2 days, begin irrigation, and maintain a certain water layer in the field for 5 days, but do not let it cover the leaf hearts of the seedlings. After the 25th day, weed and replant seedlings (remove old weeds in the field, and replant where seedlings are sparse), and apply the first seedling-promoting fertilizer, applying 5 kg to 7.5 kg of urea per 667 sq m. After 35 to 40 days of direct seeding, broadcast 25 kg of compound fertilizer or 12.5 kg of high-efficiency compound fertilizer per 667 sq m to promote tillering and bushiness of the seedlings.

Beyond the above three stages, field drying, water monitoring, topdressing, and pesticide application for pest control can follow routine management. However, because direct-seeded fields have high density, water management should be shallow in the early stage, deep in the middle stage, and controlled in the late stage, alternating dry and wet. After the seedlings have tillered sufficiently, field drying should be heavy; otherwise, lodging is likely in the late stage, and it also readily attracts pests and infection by sheath blight and the like. Author's affiliation: State-owned Jingtoushan Farm, Yangxin County, Hubei