Detailed Explanation of Key Techniques for High-Yield Cultivation of Hybrid Rice

1. Seedling Raising (Dry Seedling Raising Technique)

1. Seed treatment and germination acceleration

Before soaking the seeds, sun-dry them for 1-2 days, rinse with clean water, remove the empty and shriveled grains, and put the seeds in a nylon mesh bag. Then soak the seeds in a 500-fold dilution of 50% carbendazim wettable powder for 24 hours. Take the seeds out, wash them clean with clean water, place them in a plastic bucket on a raised layer to keep them warm for about 24 hours, and sow when the seeds show white sprouts.

2. Seedbed preparation

Before raising seedlings, choose a plot that is sheltered from the wind, faces the sun, has fertile soil, few weeds, and a good water source and water quality. Apply 1000 kg of decomposed fine farmyard manure, 40 kg of calcium superphosphate, and 15 kg of potassium sulfate per mu, and spread them evenly over the seedbed surface. Break the soil into fine crumbs, level it, and divide it into beds 1.2 m wide. The bed length is generally about 10 m and must not exceed 15 m.

3. Sow at the right time, sow in mid-March

Before sowing, select fertile, loose soil of the same soil type as the seedling bed fertilized soil or bed soil, sieve it, and use it for covering the seeds after sowing.

First, prepare the seedling bed well and press it level, then spray clean water, preferably soaking it thoroughly. Evenly broadcast the treated rice seeds onto the seedling bed, gently press them into the soil with a wooden board, then evenly spread the pre-prepared covering soil over the seedling bed. The covering thickness should be such that the grains are no longer visible, generally 0.5-1 cm.

After covering the seeds, spray herbicide: use 110 ml of 12% butachlor emulsifiable concentrate per mu, dilute with water, and spray evenly, then build arches and cover with plastic film.

4. Management

Water management for seedlings: after sowing, water according to soil moisture conditions. During the entire seedling period, watering is generally done 3-5 times.

Fertilization: (1) Weaning fertilizer: at the one-leaf-one-heart stage, apply 10 kg of urea per mu. (2) Dowry fertilizer: one week before transplanting, apply 10 kg of urea per mu.

Weeding: mainly by manual pulling.

Pest and disease control: about 10 days after emergence, spray with a 500-fold dilution of 50% carbendazim wettable powder. About 25 days after emergence, use 30 g of 75% tricyclazole wettable powder plus 50 g of 90% monosultap technical powder per mu, dilute with 50 kg of water, stir thoroughly, and spray. Three days before transplanting, use 30 g of 75% tricyclazole wettable powder plus 120 g of 20% yekuling wettable powder per mu, dilute with 50 kg of water, stir thoroughly, and spray.

2. Transplant at the right time, transplant in late April, with a seedling age of about 45 days.

1. Field preparation: When harrowing the field for the last time, close the field water well. Apply 40 kg of ammonium bicarbonate, 40 kg of calcium superphosphate, 10 kg of potassium sulfate, and 2 kg of zinc sulfate per mu as basal fertilizer.

2. Planting specifications: (1) Single-row strip planting: spacing 4×6 (cun), 25,000 clumps per mu, with 1-2 seedlings per clump. (2) Double-row strip planting: spacing 4×(4+8) cun, 25,000 clumps per mu, with 1-2 seedlings per clump.

3. Field management

1. Water management: keep water about 1 cun deep to promote greening, and shallow water to promote tillering. When enough tillers have developed, drain and dry the field to control ineffective tillering. Dry until the field cracks and white roots turn over for the tiller control to be effective. During the booting stage, irrigate frequently. During the grain-filling and maturity stages, keep the field alternately dry and wet, mainly wet.

2. Topdressing: (1) 5-7 days after transplanting, apply 7 kg of urea per mu as green-turning and tillering fertilizer. Combined with chemical weeding, apply 0.4-0.5 kg of nitrofen per mu mixed with chemical fertilizer and broadcast.

(2) At the jointing and booting stage, apply 10 kg of urea per mu or 10 kg of NPK compound fertilizer.

4. Pest and disease control

The main rice diseases include rice blast, bacterial leaf blight, and bacterial leaf streak.

Rice blast: for seedling blast, spray 45% sulfur azole at 1200-fold dilution in the seedling field. For leaf blast, spray 40% emulsifiable concentrate Fuji-One at 1800-fold dilution, and spray again after 7 days. The most effective time to control neck blast is when 80% of the panicles are about to break open; spray 75% tricyclazole wettable powder at 1000-fold dilution, and spray once more after 7 days to effectively control a major outbreak of the disease.

Bacterial leaf blight and bacterial leaf streak: at the early stage of disease, spray 10% yekujing wettable powder at 2000-fold dilution or agricultural streptomycin at 1000-fold dilution per mu, and spray again after 7 days.

If rain falls within 3-4 hours after spraying any pesticide, it should be reapplied the same day or the next day so that the control effect can be achieved.

Insect pest control: the main rice pests are rice planthoppers and stem borers. Rice planthoppers can be controlled by spraying 20% bichongling at 1000-fold dilution or fipronil at 10 ml per mu. Pyrethroid pesticides must not be used to kill this pest, and control should be repeated once after 5 days. For the striped stem borer, spray 150 ml of 25% bisultap wettable powder or mix 200 ml with sand and broadcast. The rice leaf roller is a highly destructive pest; apply 1.0-1.5 kg of 2.5% trichlorfon powder per mu by broadcasting, or spray 50% fenitrothion or 90% trichlorfon crystals at 1000-fold dilution.

5. Harvest at the right time

Harvesting when the rice grains are fully mature can effectively maximize the product harvested. Harvesting too early or too late will affect product yield.