Qiangliangyou 373

Variety Name: Qiangliangyou 373

Approval Number: National Rice Variety Approval No. 20216066, National Rice Variety Approval No. 20206005

Breeding Institution: Hunan Aopulon Technology Co., Ltd.

Variety Origin: Strong 11S × Ao R373

Characteristics: A indica-type two-line hybrid rice variety. When grown as a single-season medium-duration rice in the middle and lower reaches of the Yangtze River, its total growth period is 134 days, 0.2 days earlier than the control variety Fengliangyou No. 4. Plant height is 124.5 cm, panicle length 25.6 cm, with 153,000 effective panicles per mu; each panicle bears 229.5 grains, with a seed-setting rate of 84.4% and a 1,000-grain weight of 25.0 g. Resistance: the comprehensive blast disease index over two years was 3.9 and 3.5, respectively; the panicle-neck blast damage rating reached the highest level of 7; bacterial leaf blight rating was 7; brown planthopper resistance rating was 9, indicating high susceptibility to brown planthopper, moderate susceptibility to blast, and moderate susceptibility to bacterial leaf blight; the variety exhibits strong heat tolerance during heading. Key grain-quality parameters: milled-rice recovery rate 65.8%, degree of chalkiness 3.6%, amylose content 14.9%, gel consistency 72 mm, alkali-labile value 6.5, and length-to-width ratio 3.3, meeting the Grade III standard stipulated in the agricultural industry’s “Quality Standards for Edible Rice Varieties.”

Yield Performance: In 2018, the variety was included in the regional trial for the late-maturing medium-grain indica rice group in the middle and lower reaches of the Yangtze River, achieving an average yield of 701.43 kg per mu, a 4.88% increase over the control variety Fengliangyou No. 4. In the follow-up trial in 2019, the average yield was 674.29 kg per mu, representing a 2.54% increase over Fengliangyou No. 4. Over the two-year regional trial period, the average yield was 687.81 kg per mu, a 3.72% increase compared with the control. In the 2019 production trial, the average yield was 658.26 kg per mu, a 5.15% increase over Fengliangyou No. 4.

Key cultivation techniques: 1. Precision seeding and robust seedling cultivation: For mid-season rice, sow in mid-to-late April; for transplanted seedlings, use 1.0–1.2 kg of seed per mu; for direct-seeded or broadcast-transplanted rice, use 1.5–2.0 kg per mu. Strengthen fertilizer and water management during the seedling stage and effectively control brown planthoppers. 2. Timely early transplanting to promote tillering: Transplant transplanted seedlings when they have 5–6 leaves, with a seedling age of 25–30 days; transplant dry-seeded seedlings when they have 3.5–4 leaves, with a seedling age of 15–18 days. Adopt moderate planting density and increase the number of basic tillers by planting more seedlings—use a planting spacing of 20 cm × 30 cm, with three seedlings per hill, resulting in 80,000–100,000 basic tillers per mu. 3. Enhanced fertilizer and water management with increased phosphorus and potassium application: Apply a heavy base fertilizer, using 35–40 kg of high-concentration compound fertilizer or 45–50 kg of ordinary compound fertilizer per mu; apply tillering fertilizer early—5–7 days after transplanting, apply 8–10 kg of urea per mu; and 20–25 days after transplanting, apply 8–10 kg of potassium chloride per mu. Apply panicle and grain fertilizer judiciously: at the end of the drying period before panicle initiation, combine this with irrigation, and based on field conditions, apply 10–12 kg of high-concentration compound fertilizer and 12–15 kg of potassium chloride per mu to promote large panicles with many grains and strong grain filling. 4. Scientific water management and disease–pest control: Maintain a shallow layer of water during the green-up stage; use shallow and moist conditions for tillering; conduct drying of the field once the required number of tillers has been achieved; keep shallow water during panicle initiation and heading; alternate between wet and dry conditions during grain filling; drain the field 6–8 days before harvest. Implement timely control of sheath blight, blast, false smut, brown planthoppers, and stem borers, with particular emphasis on blast.

Review and Approval Opinion: This variety meets the national standards for rice variety approval and has been officially approved. It is suitable for single-season mid-season rice cultivation in the Yangtze River basin of Hubei Province (excluding the Wuling Mountain area), Hunan Province (excluding the Wuling Mountain area), Jiangxi Province, Anhui Province, and Jiangsu Province, as well as in the mid-season rice-growing regions of Zhejiang Province, northern Fujian Province, and southern Henan Province—provided these areas are low-incidence zones for blast disease. Planting is not recommended in areas with severe blast disease outbreaks.