Technical Operating Procedures for Producing Green Rice through Rice-Duck Symbiosis

I. Rice Production and Management
1. Base Selection
To establish a green rice planting base, one should select paddy fields with fresh air, a fine ecological environment with good vegetation, good external isolation conditions, abundant water sources, pure water quality, complete ditch systems, high soil organic matter content, no pollution, few pest and disease occurrences over the years, and concentrated contiguous plots that are convenient for large-scale production.
2. Variety Selection
In accordance with local ecological conditions and the occurrence of pests and diseases, select varieties with high photosynthetic efficiency, insect resistance, disease resistance, strong stress resistance, and high and stable quality and yield according to local conditions, with one variety per county and large-scale planting. Main recommended varieties: Early rice: Jinyou 463, Jinyou 402, Jinyou 974, Zhongyou 402, Zhuliangyou 02, Jinyou 71, etc.; Second late rice: Shanyou 46, Jinyou 207, Zhongyou Gui 99, etc.; First late rice: Liangyou Peijiu, II You 838, Boyou Gan 28, II You 906, Ganwanshan No. 30, etc.
3. Cropping System
Vigorously promote the green manure-rice-rice and green manure-rice cropping systems.
4. Sowing and Seedling Raising
(1) Field selection and basal fertilizer application. Within the already designated paddy field area, reserve sufficient seedling fields at a ratio of seedling field to main field of 1:8-10; for early rice using dry-bed seedling raising, reserve sufficient seedling fields at a ratio of 1:30. Before plowing the seedling field, apply 1000 kg of fully decomposed pig and cattle manure per mu as basal fertilizer; during land preparation, apply 30 kg of calcium magnesium phosphate fertilizer mixed with 15 kg of ammonium bicarbonate per mu as surface fertilizer. If using seedling strengthening agent for seedling raising, use 0.8 kg of seedling strengthening agent per 10 square meters of seedling bed, apply it evenly on the surface of the seedling bed, and mix it evenly with the surface soil of the seedling bed.
(2) Seed treatment. Before sowing, sun the seeds for 1-2 days; after removing shriveled seeds by water selection, soak the seeds intermittently in lime water. For early rice seeds, first pre-soak in clean water for 12 hours, drain for 12 hours; after soaking in 1% lime water for 12 hours, wash the seeds clean with clean water, then soak in clean water for 12 hours, and then germinate until the seeds break open before sowing. For first late rice and second late rice, the seed soaking time is 36 hours; do not germinate, sow the grain directly.
(3) Seed quantity per mu. ① Hybrid rice: generally the seed quantity per mu for early rice is 1.5-2 kg, and for first late rice and second late rice is 1-1.5 kg. ② For conventional rice, the seed quantity per mu for early rice, first late rice, and second late rice is generally 2.5-3 kg.
(4) Sowing time. ① Early rice sowing: generally in mid-to-late March. In early April, seize clear weather for sowing; sow late-maturing and medium-maturing varieties first, then early-maturing varieties; for direct-seeded fields, sowing should be from April 5-10, and for early-maturing varieties no later than April 15. ② First late rice sowing: generally in mid-to-late May; try to ensure that the initial heading and grain-filling period of rice avoids the high-temperature season. ③ Second late rice sowing: generally sow late-maturing varieties from June 5-15, medium-maturing varieties from June 15-25, and early-maturing varieties from the end of June to early July; ensure that rice can safely reach full heading before the arrival of cold dew wind.
(5) Seedling raising methods. ① Early rice generally uses dry-bed seedling raising or plastic soft tray seedling raising; plastic tray seedling raising requires preparing 50 trays with 561 holes per mu of main field for throwing transplanting, and implementing film-covered heat-preserving seedling raising; those sown after Qingming can use open-field wet seedling raising. ② First late rice and second late rice generally use the wet sparse sowing strong seedling raising method; for throwing transplanting, the plastic tray seedling raising method is used, requiring 55-60 trays with 434 holes per mu of main field.
5. Transplanting (Throwing Transplanting)
(1) Main field land preparation. Early rice main fields should be plowed once, harrowed three times, and leveled once; first late rice and second late rice main fields should be rolled three times or more, so that the main field is muddy on top and firm below, and the field is as level as a mirror.
(2) Basal fertilizer application in the main field. ① For early rice main fields, apply 1500 kg of green manure (milk vetch) or 1000 kg of barnyard manure per mu as basal fertilizer, and then apply 25-30 kg each of ammonium bicarbonate and calcium magnesium phosphate fertilizer during field preparation. ② For first late rice main fields, apply 1000 kg of barnyard manure per mu 15-20 days before transplanting, and apply 30 kg of ammonium bicarbonate and 25-30 kg of phosphate fertilizer per mu during field preparation. ③ For second late rice main fields, return 150-200 kg of dry rice straw to the field or apply 1000 kg of barnyard manure per mu, and apply 25-30 kg of ammonium bicarbonate and 25-30 kg of phosphate fertilizer per mu during field preparation.
(3) Transplanting (throwing transplanting)
① After early rice seedlings reach 3.5-4 leaves, they can be lifted with soil for transplanting; after first late rice and second late rice seedlings reach 4.5-5 leaves, they can be lifted for transplanting.
② For early rice hybrid seeds, plant 2-3 grain seedlings per hill, with 20,000-22,000 hills per mu; for conventional rice, plant 4-6 grain seedlings per hill, with 20,000-22,000 hills per mu.
③ For first late rice and second late rice hybrid seeds, plant 1-2 grain seedlings per hill, with about 20,000 hills per mu; for conventional rice seeds, plant 4-5 grain seedlings per hill, with about 20,000 hills per mu.
④ Transplant straight and evenly; early rice should be transplanted shallowly, and late rice should be transplanted appropriately deeply.
⑤ For throwing transplanting, early rice should be thrown with enough seedlings for 50 small-hole seedling trays, and first late rice and second late rice should be thrown with enough seedlings for 60 large-hole seedling trays; after throwing transplanting, pick out a working row every 3 meters of width.
⑥ Transplant or throw transplant with shallow water, and avoid transplanting or throw transplanting in windy and rainy weather.
6. Main Field Management
① Water management
During the tillering stage, maintain 1 cun of water for green-up, shallow water for tillering, and drain the field for sun-drying when enough seedlings are reached (80% of the planned seedling number); during the jointing stage, continue sun-drying the field, begin rewatering when the second leaf from the top shows its tip, and maintain shallow water for booting and budding; during the heading and maturation stage, maintain shallow water for heading, and alternate dry and wet irrigation for grain filling and plump seeds, preventing too early water cutoff.
① Fertilization
During the tillering stage, apply tillering-promoting fertilizer; 6-7 days after transplanting, in combination with manual weeding, apply 7-10 kg of urea and 8-10 kg of potassium chloride per mu (the amount of tillering-promoting fertilizer for first late rice and second late rice can be larger); during the jointing and booting stage, apply flower-promoting and flower-preserving fertilizer according to seedling condition; for rice fields with weak growth, apply 2-3 kg of urea per mu; during the heading and maturation stage, apply plump-grain fertilizer; from the breaking stage to before heading, apply plump-grain fertilizer as foliar topdressing according to seedling condition, using 100 g of monopotassium phosphate and 0.5 kg of urea per mu mixed with 60 kg of water for foliar spraying.
7. Integrated Control of Diseases, Insects, Weeds, and Rodents
(1) Disease, insect, and weed control
Mainly use agricultural and biological control, appropriately supplemented with biological pesticides.
① Agricultural control. Select varieties with strong disease and insect resistance; deep-water pupa killing: irrigate more than 3 cun before Qingming and maintain for 2-3 days; advocate healthy cultivation to enhance disease and insect resistance.
② Biological control. Focus on promoting the rice-field duck-raising model, using ducks to control insects and weeds, and controlling pests such as rice grasshoppers, rice planthoppers, rice leafhoppers, as well as weed damage.
③ For sheath blight control, spray 450 mL of 5% Jinggangmycin aqueous solution per mu; for rice false smut control, at the initial stage of disease occurrence, spray 450 mL of Jinggangmycin per mu
aqueous solution.
① Rodent control
Where conditions permit, advocate raising cats to prevent rodents and manually placing mousetraps, 5 per mu, to control rodent damage.
8. Harvesting, Storage, and Transportation
(1) When early rice is 85% yellow-ripe and late rice is 90% yellow-ripe, harvest promptly in clear weather.
(2) Harvest, dry, collect, and store separately by variety.
(3) Use a threshing machine for threshing; it is forbidden to spread the grain on the ground for rolling and threshing.
(4) Use bamboo mats for drying grain; it is forbidden to dry grain on asphalt or cement ground or yellow mud and sand ground to prevent pollution.
(5) Use bamboo baskets, hemp bags, grain buckets, etc., for rice storage and transportation.
II. Duck Raising and Management
1. Preliminary Preparation
(1) Select small and medium-sized fine duck breeds with vigorous vitality, wide adaptability, tolerance to coarse feed, and good stress resistance. The recommended breeds are Ji'an red-feathered duck, Shanma duck, and other dual-purpose meat and egg duck breeds.
(2) Prepare about 2.5 kg of high-quality nylon net per mu of main field, and prepare 60 to 100 bamboo or wooden poles with a diameter of more than 1 cm and a length of more than 120 cm.
2. Management during the Duckling Stage
(1) 24 hours after ducklings hatch, put each duckling's beak into water 2-3 times to develop the habit of drinking water and prevent death from dehydration in the body.
(2) Feed each duck 500 g of complete feed plus a small amount of cooked rice over 10-15 days; afterward, feed with cooked rice plus rice grain, crushed corn, and other grain-type feed until each duck reaches more than 75 g, then release into the main field.
(3) When the indoor temperature is below 20°C, use a large light bulb or infrared lamp for heating, and take care to prevent ducks from piling up and disperse them promptly.
(4) The floor of the rearing room and the feeding (watering) utensils must be disinfected with 25% Lysol water or 20% lime water, and a small amount of oxytetracycline should be added to the feed.
(5) When ducklings reach 100-125 g (25 days after hatching), vaccinate against duck plague.
3. Main Field Duck Management
(1) When ducklings are 20 days old after hatching, weigh more than 100 g, rice has been throw-transplanted for 15 days or transplanted for more than 12 days, they can be released into the main field (adult ducks should be delayed by 2-3 days).
(2) The stocking density for adult ducks is about 15 birds per mu; for young ducks, it can be appropriately increased according to conditions.
(3) Use an area of about 2 mu as one block, and surround the field with three-finger nylon net to form an escape-prevention enclosure; the enclosure net is 60 cm high, with a support pole erected every 1.5-2 m.
(4) In one corner of the field, build a duck house calculated at one square meter per 10 ducks; the roof of the house should be covered to avoid sun and rain, with three sides enclosed, but it must be ventilated and breathable; the bottom of the house should be laid flat with wooden boards or bamboo boards, and a water pit 2 times the size of the duck house and 50-60 cm deep should be dug below the house.
(5) Open several high-yield ditches 35 cm wide and 30 cm deep.
(6) Supplement-feed each duck daily with 50-100 g of rice grain, corn, duckweed, etc.; pay attention to feeding at fixed times and fixed locations, and adjust the feeding amount as appropriate; it must not be too much or too little.
(7) It is strictly forbidden to feed with moldy or foul-smelling plant feed or foul-smelling, maggot-infested animal feed.
(8) Before spraying pesticides on rice, lure the ducks into the duck house and confine them; the ducks can be released the next day after spraying.
4. Later Stage Management
(1) Collect the ducks at the rice milk-ripe stage to prevent ducks from eating rice ears. To facilitate duck collection, during normal feeding, cultivate the habit that ducks gather when they hear a certain sound.
(2) The collected ducks can be kept at home or confined in field houses for feeding.
(3) For ducks confined in field houses, after rice harvest, promptly return them to the field and release them, letting the ducks peck at fallen grain and insects in the field.
5. Points for Attention
(1) Use low-toxicity, high-efficiency, low-residue pesticides to control rice diseases and insect pests, and avoid using pesticides as much as possible.
(2) When building field duck houses, consideration should be given to preventing rodent damage.
(3) During pesticide application in rice fields, ducks should be collected and removed from the field promptly, and released into the field again only after the safe interval period.
(4) During the safe interval period of pesticide application in rice fields, duck drinking water and rice field water should be kept separate to prevent duck poisoning and contamination of duck products.