Tianliangyou 666

Variety Name: Tianliangyou 666

Approval Number: National Rice Variety Approval No. 20216057

Breeding Institution: Hunan Aopulon Technology Co., Ltd., Hunan Agricultural University

Variety Origin: Tianan S×AoR 66

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 131.4 days, 3.6 days earlier than the control variety Fengliangyou No. 4. Plant height is 107.1 cm, panicle length is 26.8 cm, with 169,000 effective panicles per mu; each panicle bears 202.6 grains, with a seed-setting rate of 87.8% and a 1,000-grain weight of 24.0 g. Disease resistance: the comprehensive blast disease index over two years was 4.3 and 3.9, respectively; the panicle-neck blast damage rating reached the highest level of 5; bacterial leaf blight was rated at level 7; brown planthopper resistance was rated at a high level, with strong susceptibility to brown planthopper, moderate susceptibility to blast, and susceptibility to bacterial leaf blight; heat tolerance during heading was relatively strong. Key rice quality parameters: milled rice recovery rate of 66.2%, degree of chalkiness of 0.5%, amylose content of 15.9%, 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 middle and lower reaches of the Yangtze River, achieving an average yield of 667.15 kg per mu, a 4.16% increase over the control variety Fengliangyou No. 4. In the follow-up trial in 2018, the average yield was 688.40 kg per mu, representing a 2.49% increase over Fengliangyou No. 4. Over the two-year regional trial period, the average yield was 677.77 kg per mu, a 3.31% increase compared with the control. In the 2018 production trial, the average yield was 631.94 kg per mu, a 3.38% 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 plant 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 at 35–40 kg per mu of high-concentration compound fertilizer or 45–50 kg per mu of ordinary compound fertilizer; apply tillering fertilizer early—8–10 kg of urea per mu 5–7 days after transplanting, and 8–10 kg of potassium chloride per mu 20–25 days after transplanting. 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 per mu of high-concentration compound fertilizer and 12–15 kg per mu of potassium chloride to promote large panicles with many grains and strong grain filling. 4. Scientific water management and disease–pest control: Maintain a shallow water layer for green-up; alternate between shallow and moist conditions during tillering; conduct drying of the field once sufficient tillers have formed; 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. Promptly control sheath blight, blast, false smut, brown planthoppers, and stem borers, among others.

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 rice-growing areas of Hubei Province (excluding the Wuling Mountain region), Hunan Province (excluding the Wuling Mountain region), Jiangxi Province, Anhui Province, and Jiangsu Province, as well as in the mid-season rice-growing areas of Zhejiang Province, the northern rice-growing areas of Fujian Province, and the southern rice-growing areas of Henan Province—provided that these regions are low-incidence areas for rice blast.