Detailed Explanation of Super-High-Yield Cultivation Techniques for Shengtai No. 1 Rice

Shengtai No. 1 is a super-high-yield, disease-resistant new variety bred by the Rice Research Institute of the Guangdong Academy of Agricultural Sciences. It passed crop variety approval in Guangdong Province and Shaanxi Province, and received the first-ever subsidy from the Ministry of Agriculture of the People's Republic of China for high-quality and special-purpose new varieties of major crops. When cultivated in Jieyang City, its full growth period is about 132 days for the early crop and about 122 days for the late crop, belonging to the medium-late maturity type suitable for both early and late seasons. Its stem and leaf morphology is coordinated and rational, with a well-developed deep root system, medium-strong tillering ability, good fertilizer tolerance and lodging resistance, suitable for planting in areas with medium or higher fertility, with obvious yield-increasing effects. The panicles are large and long, with dense grain setting, and the panicle-grain structure is excellent, with the main panicle having more than 500 total grains and great high-yield potential. Jieyang City introduced and planted it in the early crop of 1996. In last year's late crop, Qiaonan Village, Pandong Town, planted 1000 mu in contiguous fields, with an average yield of 622.8 kg per mu, and super-high-yield plots reaching 697.3 kg. This marks another successful step forward in our province's rice breeding for both high quality and high yield. Its super-high-yield cultivation techniques are introduced as follows:

I. Cultivating Strong Seedlings and Transplanting with Soil Only sparse sowing can produce strong seedlings; good seedlings are half the rice. The sowing rate per mu of seedling bed is 10-15 kg, sown sparsely and evenly. After sowing for the early crop, cover with plastic film to protect against cold; for the late crop, use shade netting to protect against heavy or torrential rain. For the early crop seedling bed, require plowing and sun-bleaching, then apply superphosphate mixed with manure water as a liquid fertilizer; when making the seedbed, broadcast 20 kg of compound fertilizer per mu on the bed surface and press it into the surface soil. After sowing, cover the bed surface with plant ash to retain warmth and moisture. After removing the film, immediately spray 150 mg/kg chlormequat and apply fertilizer in time to promote tillering. For the early crop, use decomposed manure or imported compound fertilizer diluted with water and applied as a liquid, from dilute to concentrated; for the late crop, imported compound fertilizer or a small amount of urea diluted with water can be applied. The send-off fertilizer should be applied 4-5 days before transplanting for the early crop and 3-4 days before transplanting for the late crop. During the seedling stage, promptly control pests and diseases and apply send-off pesticide. At transplanting, each seedling is required to carry 2-3 tillers. When pulling seedlings, do not wash the roots; transplant with soil to reduce transplanting injury and promote early greening and early tillering. For the late crop, it is best to transplant on cloudy days or after 4 p.m.

II. Soil Improvement and Fertilizer Enhancement in the Main Field The root system of Shengtai No. 1 can grow deep to 70 cm underground, so a suitable soil environment should be created. The method is: deep plow the main field to more than 22 cm; for the early crop, when fully sun-bleached, apply 150 kg of manure water mixed with 30 kg of superphosphate per mu as a liquid over the field surface; when preparing the field in spring, broadcast 250 kg of spent mushroom substrate or 300-400 kg of dried chicken and duck manure, and turn it under into the bottom layer. For the late crop, require 50%-70% of rice straw to be returned to the field; after spraying straw-decomposing agent, compost and turn it under, and apply 25 kg of lime to accelerate decomposition and neutralize acidity.

III. Shallow Transplanting and Even Spacing, Timely Checking and Replanting of Missing Seedlings The main field should be harrowed level one day in advance and drained to a thin water layer to ensure transplanting quality. Before transplanting, it is advisable to soak seedling roots in amino acid compound micro-fertilizer for 1 hour. Footprints left during transplanting should be smoothed out, with shallow transplanting and even spacing, ensuring seedlings stand upright, and checking and replanting missing seedlings should be carried out on the 2nd day after transplanting.

IV. Scientific Fertilization in the Main Field

Base fertilizer: For the early crop, apply 20 kg of superphosphate and 25-30 kg of ammonium bicarbonate per mu as surface fertilizer (because early spring temperatures are lower and urea has a slower fertilizer effect, ammonium bicarbonate is preferable); for the late crop, apply 30 kg of superphosphate and 10 kg of urea per mu as surface fertilizer.

Topdressing: Following the management model of "promoting early growth, striving for large panicles, increasing grain filling, raising grain weight, and maintaining late-season vigor," for the early crop the first tillering-promoting fertilizer is applied on the 3rd day after transplanting with 6 kg of urea mixed with 100 ml of 60% butachlor per mu, broadcast together with weed control; the second tillering-promoting fertilizer is applied on the 8th-9th day after transplanting with 7-8 kg of urea and 7 kg of potassium chloride. The mid-term fertilizer is applied on the 28th day after transplanting (i.e., the beginning of young panicle differentiation) and at the fifth stage of young panicle differentiation, each time with 4 kg of urea and 4 kg of potassium chloride. In the later stage, if the weather is good and sunlight is sufficient, and the lower leaf sheaths of the rice show slight chlorosis, a full-heading fertilizer may be applied, with 3 kg of urea and 4 kg of potassium chloride per mu, or 10 kg of compound fertilizer. The main field receives 19.5 kg of pure N, 4.8 kg of P2O5, and 19.4 kg of K2O per mu, with an N:P:K ratio of 1:0.3:1.0, and the nitrogen application ratio for the early, middle, and late stages is approximately 67:23:10.

For the late crop, the first tillering-promoting fertilizer is also applied on the 3rd day after transplanting, with 5-6 kg of urea mixed with 100 ml of butachlor per mu; the second tillering-promoting fertilizer is applied on the 8th day after transplanting, with 6.5 kg of urea and 6 kg of potassium chloride per mu; the mid-term fertilizer is applied at the beginning of young panicle differentiation and at the fifth stage of young panicle differentiation, with 5 kg of urea and 4 kg of potassium chloride per mu each time; the late-stage fertilizer is applied at full heading and 10 days after full heading, depending on weather conditions, with 3.5 kg of urea and 3 kg of potassium chloride each time, or 7.5-10 kg of compound fertilizer broadcast. For the late crop, the main field receives about 19.9 kg of pure N, 4.7 kg of P2O5, and 22.0 kg of K2O per mu, with an N:P:K ratio of 1:0.24:1.10, and the nitrogen application ratio for the early, middle, and late stages is 63:23:14.

V. Scientific Water Use, Regulating Fertilizer with Water Field water management should grasp shallow-water tillering. For the late crop, before each application of tillering-promoting fertilizer, intentionally irrigate first and then drain to reduce acidic and toxic substances produced by straw decomposition in the soil layer. When the effective panicle seedling number reaches 80%, light field drying can begin, and when sufficient seedlings are reached, sun-dry the field; in the mid-to-late stages, alternate wetting and drying, which can regulate fertilizer with water and promote strong rice root activity, tough and healthy stems, and upright leaves, presenting a lodging-resistant posture. However, from the early heading stage to the full heading stage, a shallow water layer must be maintained, and premature water cutoff must be prevented in the later stage.

VI. Snail and Rat Control, Disease and Pest Prevention and Treatment High-yield fields are prone to damage by field rats, so comprehensive rat poisoning should be carried out twice before field drying. If pesticide is applied after field drying, the rats will already have entered the field to damage the rice seedlings. For the late crop, snail damage is especially severe, so a comprehensive snail kill should be carried out once before transplanting. During the tillering stage, apply Tian'an as a protectant; after rewatering and before row closure, apply jinggangmycin depending on weather conditions to control sheath blight; in the early and middle stages of rice production, strictly prevent thrips, rice locusts, stem borers, and planthoppers; from the breaking stage to the full heading stage, comprehensively control panicle neck blast, sheath blight, and rice planthoppers.