High-Yield Cultivation Techniques for the Tianjin Hybrid Japonica Rice 10 You 18
10 You 18 is a three-line hybrid medium japonica combination bred by the Tianjin Rice Research Institute by crossing the self-developed male sterile line 10A with the self-developed restorer line R148. This combination performed outstandingly in the 2000 Tianjin main-season hybrid japonica rice new combination screening, and was then named Jin You 9603. From 2001 to 2003, it completed the national regional trial in the Yu Japonica 6 group, and in 2004 passed national variety approval, being named 10 You 18. In large-scale planting, 10 You 18 has shown the characteristics of good high and stable yield, excellent grain quality, strong disease and stress resistance, wide adaptability, and excellent comprehensive traits. Large-scale planting has already begun in suitable provinces and cities such as Jiangsu, Anhui, Henan, Shandong, Shaanxi, Tianjin, and Hebei, with broad development prospects. To better support the promotion and application of this combination, based on recent experimental research and demonstration performance in various locations, its large-scale high-yield cultivation techniques are introduced as follows:
Cultivation Management
In cultivation, reasonable regulation should be carried out around the high-yield cultivation strategy of "increasing transplanting density and promoting early tillering in the early stage; strengthening plants and stalks in the middle stage to promote large panicle formation; and nourishing roots and preserving leaves in the late stage to increase seed-setting rate." 10 You 18 has medium tillering ability, so emphasis should be placed on cultivating multi-tiller strong seedlings during the seedbed period. Through sparse sowing, the aim is for each plant to carry 3 to 4 strong tillers at transplanting. For the sowing rate on clean seedbeds, dry-raised seedlings should not exceed 50 kg/667 sq m, and wet-raised and water-raised seedlings should not exceed 40 kg/667 sq m, with seedling age not exceeding 35 days.
Fertilization Management
The base fertilizer in the seedbed is generally 12.5 kg/667 sq m of diammonium phosphate, 7.5 kg/667 sq m of urea, 5.0 kg/667 sq m of potassium sulfate, and 1.5 kg/667 sq m of zinc sulfate. Pay attention to the prevention and control of diseases, insects, and weeds. Under the premise of strong seedlings, the seedling age should preferably be 30 to 35 days, and transplanting should be shallow and uniform. Under medium-to-high fertility conditions, the plant-row spacing is 13.3 cm x 25 cm, with 2 to 3 plants per hill, planting 18,000 to 20,000 hills/667 sq m, and a basic population of about 80,000 to 100,000/667 sq m. Lean fields and late-transplanted fields should be appropriately densified, and the transplanting density can be increased to 22,000 hills/667 sq m. 10 You 18 has deep roots and luxuriant leaves, strong absorption capacity, little ineffective growth, little waste of nutrients and photosynthates, and high fertilizer use efficiency. Fertilizer and water management should adopt the principle of "promoting in the early stage, controlling in the middle stage, and slightly supplementing in the late stage," with nitrogen, phosphorus, and potassium fertilizers used in combination, and attention paid to the application of zinc fertilizer.
The amount of fertilizer applied depends on the paddy field fertility and yield target. For fields with a target of more than 700 kg/667 sq m, 15 to 20 kg of nitrogen, 8 to 10 kg of phosphorus pentoxide, and 15 to 20 kg of potassium oxide are required per 667 sq m. This is equivalent to 35 to 45 kg of urea per 667 sq m, 45 to 50 kg of calcium magnesium phosphate fertilizer with a phosphorus content of 16%, or 15 to 20 kg of diammonium phosphate, and 15 to 20 kg of potassium sulfate.
In terms of fertilization method, if the base fertilizer is mainly organic fertilizer, the amount should be no less than 1800 kg/667 sq m; if mainly chemical fertilizer, the chemical fertilizer application amount should account for 30% of nitrogen fertilizer, 100% of phosphorus fertilizer, and 70% of potassium fertilizer for the whole growth period; tillering fertilizer is mainly nitrogen fertilizer, and 7 to 10 days after transplanting, the nitrogen fertilizer applied per mu should account for 50% of the whole growth period amount; panicle fertilizer is applied after sufficient tillers, field drying, and rewatering, with nitrogen fertilizer applied per mu accounting for 15% of the whole growth period amount and potassium fertilizer 25%; grain fertilizer is applied after heading, and at application time should be applied according to the seedlings and weather as appropriate. When the population leaf color fades and the weather is mostly clear and fine, apply grain fertilizer; otherwise, do not apply. Generally, grain fertilizer nitrogen and potassium fertilizer account for 5% of the total, and foliar spraying can also be carried out, using nutritional foliar fertilizer for foliar spraying at the heading and flowering stage.
Irrigation Management
In the early stage, shallow-water irrigation is used (green-return stage). After rice transplanting, because the root system's ability to absorb water is relatively weak, and when high temperature and strong wind occur, leaf transpiration is relatively large. Therefore, after transplanting, a water layer of 3 to 5 cm should be maintained. After the rice turns green, intermittent irrigation is adopted, that is, irrigating shallow water once, letting it dry naturally, and when there is water in the footprints but no water on the field surface, irrigating once again, and repeating this cycle. After the rice has enough tillers, field drying is used to control the growth of ineffective tillers and increase soil permeability, achieving effects such as root growth, stalk strengthening, and lodging resistance. Field drying operation: for low-lying fields where the seedlings grow too vigorously, close up relatively early, leaves droop, and drainage is poor, drain and dry heavily, with the degree of field drying being that the field surface turns white, fine cracks open on the field surface, white roots appear on the surface, and the leaf color fades and stands upright, controlling ineffective tiller growth, promoting well-developed roots, and strengthening stalks. For fields with weak growth vigor, difficult irrigation, and water leakage, light exposure should be adopted. At the booting stage, moisture should be dominant, maintaining a water layer on the field surface; at the heading stage, shallow water should be maintained in the field; at the grain-filling stage, the paddy field should be alternated dry and wet to enhance soil permeability and maintain the old rice well. Water should be cut off about 7 days before harvest, and premature draining should be avoided to prevent premature senescence, affecting grain quality and reducing the seed-setting rate.
Disease Management
Before sowing, soak seeds with Jinsongling to prevent bakanae disease and rice white-tip nematode; during the seedbed period, focus on the control of pests such as rice thrips, rice water weevil, and rice planthopper, as well as weeding. Generally, Daolefeng + imidacloprid and chlorpyrifos + Zhubao + Jinbi are each used once to control pests; according to disease and pest forecasts, timely carry out field disease and pest control. Within 7 days after transplanting, use Caokexing + butachlor for timely chemical weeding, and use insecticides such as bisultap, imidacloprid, Daolefeng, and omethoate to focus on the control of the first and second generation of striped stem borer, pink stem borer, rice leaf roller, rice planthopper, and other pests; before booting, at initial heading, and at full heading, use jinggangmycin respectively to control sheath blight.
With changes in the planting system and the continuous increase in nitrogen fertilizer use, the occurrence area and damage degree of rice false smut have gradually increased. Therefore, strengthening the control of rice false smut is of great significance for the stable and high yield of 10 You 18. At present, chemical control is mainly spraying fungicides 5 to 7 days before rice panicle break. The first type is copper preparations, which were the earliest used in rice false smut control, among which DT can achieve a control effect of 80% to 96%, but this product is prone to phytotoxicity, so the dosage should be well controlled and the spraying method noted during use; the second type is antibiotics, and 30% Aimiao EC 15 to 20 mL/667 sq m has a good control effect on rice false smut, causing no phytotoxicity to rice growth and also significantly promoting rice growth and preventing premature senescence; the microbial pesticide "Wenquning" aqueous solution (2.5% jinggangmycin 10 billion viable spores/mL Bacillus subtilis) has an average control effect on rice false smut of 72.1% to 83.6%; 5% jinggangmycin 500-fold solution sprayed 5 to 7 days before panicle break can also achieve a control effect of more than 80%.