A Complete Analysis of the Key Points of High-Yield Cultivation Techniques for Two-Line Rice

Two-line rice has characteristics such as early and rapid growth in the early stage, smooth color transition in the middle stage, a long late-maturing period, tolerance to fertilizer and disease resistance, large panicles with many grains, relatively good grain quality, stable and high yield, and a more obvious yield-increasing advantage over three-line rice. Therefore, in recent years it has been promoted and applied over relatively large areas in various places. In practice, we earnestly implemented the "six improvements" measures for high-yield cultivation, gave play to the high-yield advantages of two-line rice, and achieved gratifying results.

1. Improve seedling-raising techniques and cultivate strong seedlings. According to the characteristic that two-line rice has little flexibility in seedling age, carry out classified seedling raising. In areas with good irrigation and drainage conditions, use plastic-tray seedling raising; the seedling period should preferably be 20-22 days for the early crop and about 12 days for the late crop, so as to cultivate small, strong seedlings. Where water conservancy conditions are poor, use semi-dry seedling raising; the seedling period should preferably be 25-30 days for the early crop and 18-20 days for the late crop, so as to cultivate tillering strong seedlings.

2. Improve transplanting spacing and ensure the basic number of seedlings. Strictly control seedling age, which is beneficial for early and rapid growth after throwing (transplanting), striving for large panicles, and obtaining high yield. For seedling throwing, throw and transplant at about the 3.5-leaf stage; for high-fertility fields, throw 13,000-14,000 holes per mu, for medium-fertility fields, throw 15,000-16,000 holes per mu, with 40,000-50,000 basic seedlings per mu. For transplanting, transplant at about the 6.5-leaf stage; for high-fertility fields, the transplanting spacing is 23 cm x 13 cm, with 50,000-60,000 basic seedlings per mu; for medium-fertility fields, the transplanting spacing is 20 cm x 13 cm, with 60,000-70,000 basic seedlings per mu.

3. Change traditional fertilization methods to balanced formula fertilization. Traditional fertilization methods cannot meet the growth needs of two-line rice. Based on local experience, we changed traditional fertilization habits, implemented balanced fertilization, formulated fertilization according to soil conditions, rationally matched nitrogen, phosphorus, and potassium, macroscopically controlled the total amount of fertilizer applied, and adopted the principle of heavy application at the early stage, attack at the middle stage, and supplementation at the late stage, so as to meet the needs of the growth and development of two-line rice. On the basis of applying sufficient base fertilizer, apply green-returning fertilizer early (4-5 days after throwing and transplanting), apply tillering fertilizer heavily (8-10 days after throwing and transplanting), increase the application of phosphorus and potassium fertilizer, create conditions to apply mid-stage fertilizer well, promote young panicle differentiation and development, strive for large panicles, and increase grain number. The application ratio of nitrogen fertilizer at the early, middle, and late stages is 8.5:1.5:0 for the early crop and 8:1.5:0.5 for the late crop. The ratio of nitrogen, phosphorus, and potassium should preferably be 1:0.45:0.6-0.8. Change farmers' total fertilization amount from being applied all at twice to being applied in 4-5 times according to the optimal fertilizer absorption periods. Apply N 13-15 kg, P2O5 5.5-6.5 kg, and K2O 10-12 kg per mu over the whole period.