Detailed Explanation of the Standardized Cultivation Technology Model for Daohuaxiang 2 Rice

Standardized Cultivation Technology Model for Daohuaxiang 2 Rice

1 Expected Yield Target

Target yield: 0.8 million kg/ha. Yield composition: 17-18 hills per sq m, 20-21 effective panicles per hill, 95 filled grains per panicle, 1000-grain weight 26 g.

2 Key Technical Measures

2.1 Variety Selection

Select a variety with a growth period of 138-140 days, plant height 105-110 cm, average grains per panicle 100-110, 1000-grain weight 26.5 g, yield potential 8000 kg/ha, and resistance to rice blast.

2.2 Raising Strong Seedlings

2.2.1 Greenhouse Seedling Raising in Throwing Trays Seeds 35-40 kg (quality requirements: purity 99%, cleanliness 98%, germination rate above 90%). Sun-dry seeds for 2-3 days before soaking. For saltwater selection, use saltwater with a specific gravity of 1.13 (10-12 kg salt added to 50 kg water, fresh egg exposed 1 sq cm above the surface) to achieve 100% seed plumpness. After saltwater selection, immediately rinse with clean water 2-3 times. Soak in clean water for 5-7 days until accumulated temperature reaches 100 degree-days. Germinate the soaked seeds at 25°C-32°C for 36-48 hours, with sprout length of 1 mm being optimal. High temperature for breaking the hull (32°C), moderate temperature for germination (25°C), low temperature for drying sprouts (15°C). Coat 40 kg of germinated seeds with 100 mL of 6.25% Liandun, air-dry in shade for 24 hours, then sow.

Select a seedling site that is flat, fertile, with a low groundwater table, sheltered from wind and facing the sun, and convenient for irrigation and drainage. Maintain soil fertility year-round. In the seedling field after transplanting, apply 1.5 cubic meters of high-quality farm manure, and on the seedbed apply 60-70 g/sq m of diammonium phosphate. Ratio of seedling field to paddy field is 1:80-100. Prepare seedbed soil in autumn, piling and composting paddy soil as needed for use the following year. During composting, corresponding amounts of organic fertilizer can be directly added (soil:organic fertilizer ratio 4:1), and the surface smoothed and sealed with butachlor before covering with film. Seedbed soil preparation: paddy soil and peat at 3:1, or paddy soil and decomposed pig manure at 4:1, with 2 kg of seedbed soil per tray, approximately 1000 kg of soil prepared per hectare. Each hectare requires 500 trays of 434-hole seedling trays or 550 trays of 352-hole seedling trays. Cover the greenhouse early to thaw seedbed soil and increase ground temperature. Cover the greenhouse on March 25. When air temperature stably passes 5°C, generally sow on April 8-10, sowing rate 3-4 seeds per pot, and after sowing cover with sifted fine soil 1 cm deep so no seeds are exposed.

2.2.2 Seedbed Management Before emergence, keep sealed and warm. After emergence, maintain 25°C-28°C; at the 1.5-leaf stage not exceeding 25°C; from 1.5-leaf to 3-leaf stage 20°C-25°C; 5-7 days before transplanting, remove greenhouse side skirts for full ventilation and hardening. Because pot-tray seedling raising uses less soil, water deficiency is more likely. Signs of water deficiency are the seedbed surface turning white and seedling leaves curling during ventilation. Before rice emergence, keep the seedbed soil moist. From emergence to the 1.5-leaf stage, control watering; after the 1.5-leaf stage, water as needed. For pot seedling raising, because soil nutrient space is relatively small, nutrient deficiency easily occurs after the 2-leaf stage, so appropriate topdressing should be applied. At the 2.5-leaf stage, apply 1 bag (1000 g) of seedbed-specific fertilizer per 200 trays. When barnyardgrass in the seedling field is at the 1.5-leaf stage, spray each 100 sq m of seedbed with 10 mL of 10% Qianjin (cyhalofop-butyl) emulsifiable concentrate plus 30 mL of 48% bentazone diluted with an appropriate amount of water; safety is good. At the 1.5-leaf stage of seedlings, spray 50 mL per bottle of 30% Ruimiaoqing per 50 sq m of seedbed.

2.3.3 Preparation Before Transplanting Three treatments before transplanting 2 days prior. Fertilizer treatment: apply 100 g of diammonium phosphate per sq m of seedling field. Pesticide treatment: to prevent leafminer, use 70% Admire 6-8 g per 100 sq m or 25% Actara 6-8 g per 100 sq m, diluted in 5 kg water for spraying. Rooting agent treatment: spray with Bihu (gibberellin, brassinolide, and indoleacetic acid mixture) at 5000 times dilution.

2.3 Mechanical Land Preparation

Paddy field plowing depth should be 15-16 cm; clay soil can be deeper, sandy loam can be shallower. Rotary tillage depth should reach 13-14 cm or more, combining plowing and rotary tillage. Water-based land preparation requires that the height difference not exceed one cun, and with one cun of water the mud should not be exposed; transplant after appropriate settling.

2.4 Transplanting

Begin transplanting when air temperature stably passes 13°C, generally May 10-25; the optimal transplanting period is May 15-25. Transplanting density should be 30 cm row spacing and 18-20 cm hill spacing. Seedling quantity per hectare: 430-450 trays of 434-hole seedling trays or 500 trays of 352-hole seedling trays.

2.5 Formula Fertilization

Chemical fertilizer application rates: pure nitrogen 145 kg/ha, pure phosphorus 80 kg/ha, pure potassium 120 kg/ha, zinc sulfate 25 kg/ha. Base fertilizer: before plowing, nitrogen fertilizer 45%, phosphorus fertilizer 100%, potassium fertilizer 75%. Recommended base fertilizer is 46% (12-16-18) compound fertilizer at 500 kg/ha. Topdressing: urea 150 kg/ha, ammonium sulfate 75 kg/ha, potassium chloride 50 kg. Tillering fertilizer on June 3-5: pure nitrogen 34.5 kg/ha, i.e., urea 75 kg/ha. Tillering supplementary fertilizer on June 13-15: pure nitrogen 34.5 kg/ha, i.e., urea 75 kg/ha. Panicle fertilizer on July 12-13: pure nitrogen 15 kg/ha, i.e., ammonium sulfate 75 kg/ha; pure potassium 30 kg/ha, i.e., potassium chloride 50 kg/ha.

2.6 Scientific Irrigation

Carry out scientific irrigation according to different growth and development stages of rice: shallow water for greening, shallow water for tillering, drain and sun the field when enough tillers are reached, sufficient water for booting, shallow water for heading, moist irrigation for grain filling, and draining before yellow ripeness. If low temperature occurs at the booting stage, irrigate with deep water 15-20 cm deep. For field sunning, at the critical period for effective tillering of rice, drain and sun the field for 10-15 days to reduce soil nitrogen concentration, expel harmful gases from the soil, and control ineffective tillering; the time is generally June 25 to July 10.

2.7 Integrated Control of Diseases, Insects, and Weeds

Closed herbicide treatment before rice transplanting. After 1-2 days of harrowing, apply 50% Rifit 500 mL/ha for closed treatment; transplant 2 days after closed treatment. After rice turns green, apply 50% Rifit 750 mL plus 30% bensulfuron-methyl 300 g combined with tillering fertilizer mixed with urea. If broadleaf weeds such as wild arrowhead, Monochoria, and ducktongue grass appear later, spray 2.5% Daqjie (penoxsulam) 1000 mL/ha for control. For rice blast, use 40% Fuji-One 1500 mL/ha plus 2% Kasumin 500 mL/ha or 75% (Daoyan) tricyclazole 450 g/ha plus 2% Kasumin 500 mL/ha to control panicle neck blast; application time is at the rice booting stage. For striped stem borer, use 90% Shachongdan 900 g/ha or 20% Kangkuan 150 mL/ha; control timing is determined according to insect situation forecasts from agricultural technology departments. For rice water weevil and rice weevil, use 48% Lorsban (chlorpyrifos) 750 mL/ha diluted with water for splash application or spraying.

2.8 Lodging Prevention Technology

At the late tillering stage of rice, apply dwarfing and stem-strengthening agent at 15 bags per hectare, mixed with fertilizer and broadcast, to strengthen basal internodes, making basal internodes shorter and thicker, thereby enhancing rice lodging resistance.

2.9 Mechanical Harvesting

When all grains have hardened, the upper part of the rachis is dry and the lower part yellow, grain maturity reaches 95%, and paddy moisture drops below 16%, harvest promptly with a combine harvester. At harvest, leave 25 cm high stubble and return straw to the field to increase soil organic matter and improve soil fertility.