Hong Liangyou 211

Variety Name: Hong Liangyou 211

Approval Number: National Rice Variety Approval No. 20206006

Breeding Institution: Hunan Aopulon Technology Co., Ltd.

Variety Origin: Hongfeng 80S × Ao R211

Characteristics: A indica-type two-line hybrid rice variety. When grown as a single-season mid-season rice in the upper reaches of the Yangtze River, its total growth period is 151.6 days, which is 2.5 days longer than the control variety F You 498. Plant height is 110.3 cm, panicle length is 23.3 cm, with 135,000 effective panicles per mu; each panicle bears 205.8 grains, with a seed-setting rate of 84.6% and a 1,000-grain weight of 27.5 g. Resistance: the comprehensive blast disease index over two years was 4.8 and 3.8, respectively; the panicle-neck blast damage rating reached the highest level of 7; brown planthopper resistance is rated at level 9. The variety is susceptible to blast but highly susceptible to brown planthopper. It exhibits strong heat tolerance during heading and strong cold tolerance. Key rice quality parameters include: milled rice recovery rate of 59.7%, degree of chalkiness of 2.8%, amylose content of 15.1%, gel consistency of 60 mm, alkali digestion value of 6.8, and length-to-width ratio of 3.5, meeting the Grade II standard stipulated in the agricultural industry’s “Quality Standards for Edible Rice Varieties.”

Yield Performance: In 2017, the variety was included in the regional trial for the late-maturing medium-grain indica rice group in the upper reaches of the Yangtze River, achieving an average yield of 614.04 kg per mu, a 4.4% increase over the control variety F You 498. In the follow-up trial in 2018, the average yield was 633.00 kg per mu, representing a 5.29% increase over F You 498. Over the two-year regional trial period, the average yield was 623.52 kg per mu, a 4.85% increase compared with the control. In the 2019 production trial, the average yield was 588.75 kg per mu, a 0.94% increase over the control F You 498.

Key cultivation techniques: 1. Cultivate robust, multi-tiller seedlings. In the upper Yangtze River region, where a single-season medium-duration rice is grown, sow early at the optimal time according to local ecological conditions, using 1.0–1.2 kg of seed per mu in the main field and 7–8 kg per mu in the nursery. Always treat seeds with chlorothalonil, practice sparse and even sowing, strengthen fertilizer and water management during the seedling stage, and effectively control brown planthoppers. 2. Transplant early at the right time to promote tillering. For transplanted seedlings raised in water, transplant when they have six leaves, at 30–35 days old; for transplanted seedlings raised on dry land, transplant when they have 3.5–4 leaves, at 18–22 days old. Ensure appropriate planting density: plant at a spacing of 20 cm × 30 cm, with three seedlings per hill, resulting in 70,000–90,000 basic seedlings per mu. 3. Implement moderate fertilizer and water management, reducing nitrogen application while increasing phosphorus and potassium. Apply a heavy base fertilizer: 25–30 kg of high-concentration compound fertilizer or 35–40 kg of ordinary compound fertilizer per mu. Apply tillering fertilizer early: 5–7 kg of urea per mu 5–7 days after transplanting, and 8–10 kg of potassium chloride per mu 20–22 days after transplanting. During the panicle initiation stage, increase potassium application to 12–15 kg per mu to promote larger panicles with more grains and stronger grain filling; strictly limit nitrogen application in the mid- to late stages. 4. Manage water and control pests and diseases scientifically. Maintain a shallow layer of water for green-up, alternate between shallow and moist conditions during tillering, allow the field to dry once seedlings are established, keep shallow water during panicle initiation and heading, alternate between wet and dry conditions during grain filling, and drain the field 6–8 days before harvest. 5. Timely control of pests and diseases. Based on pest and disease forecasts, apply pesticides promptly to control blast, stem borers, brown planthoppers, sheath blight, false smut, and other pests and diseases, with particular attention to blast control.