Detailed Explanation of Key Techniques for Raising Strong Seedlings for Machine-Transplanted Rice

With the improvement of the level of intensification in rice production, mechanical transplanting has become an inevitable trend. One of the keys to machine-transplanted rice production is raising strong seedlings. The following measures can produce strong seedlings:

1. Apply strong seedling agent. The strong seedling agent is usually mixed with the subsoil. First mix a small amount of fine soil with the strong seedling agent evenly, scatter it on the bottom of the seedling tray, and then add the subsoil. This avoids uneven mixing and scattering due to too much subsoil, which leads to uneven distribution of the strong seedling agent, causing seedling dwarfing and failure to emerge where too much strong seedling agent is present, resulting in seedlings pulling loose during transplanting and affecting the quality of mechanical transplanting.

2. Cover with plastic film. Because the seedling age is short, plastic film can be covered during the seedling-raising process to increase temperature and retain moisture. That is, place a row of thick bamboo poles along the edge where two seedling trays overlap in the direction of the seedling board, and then cover with film. The film then forms a roof shape, making it less likely to cling tightly to the soil surface and affect ventilation; when it rains, rainwater will flow along the film into the drainage ditch.

3. Cover with straw curtains. Seedling raising requires the covering material to maintain a light transmittance of 10%-15%. During the seedling-raising process, the film can be covered with straw, shade netting, straw mats, straw curtains, and other covering materials, with straw curtains being the best. Straw curtains are made by using two sets of plastic rope of suitable thickness, tying one straw with each, alternating one up and one down, and weaving back and forth; they can be used for many years. For every 667 sq m of field, prepare 2 straw curtains 3.5 m long and 0.6 m wide for the seedling trays. The light transmittance is uniform, which can make the seedlings neat, uniform, and strong, meeting the requirements of mechanical transplanting.