Introduction to the Characteristics of the Jiazao 312 Rice Variety

Variety source: Jiazao 935/Z9505//Z96-10

Provincial approval status: Approved in 2003 by the Zhejiang Provincial Crop Variety Approval Committee

Characteristics: This variety is conventional indica rice. Grown as early rice in the middle and lower reaches of the Yangtze River, its average whole growth period is 110 days, 2.2 days later maturing than the control Jiayu 948 and 1.2 days earlier maturing than Zhe 733. Plant height is 81.5 cm, plant type is moderate, cold tolerance at the seedling stage is strong, the population is uniform, flag leaves are erect, tillering ability is somewhat weak, panicle-grain weight is well coordinated, and color conversion at the late stage is relatively good. Effective panicles per mu are 219,000, panicle length is 19.7 cm, total grains per panicle are 108.9, seed setting rate is 78.2%, and 1000-grain weight is 25.9 g. Resistance: leaf blast grade 7, panicle blast grade 7, panicle blast loss rate 10.8%, bacterial blight grade 3, white-backed planthopper grade 9. Main rice quality indicators: head rice rate 41.7%, length-to-width ratio 3.2, chalky grain rate 33.5%, chalkiness degree 7.3%, gel consistency 83.5 mm, amylose content 14.2%.

Yield performance: In 2001, it participated in the regional trial of the early indica early-to-mid-maturing group in the middle and lower reaches of the Yangtze River, with an average yield of 490.7 kg per mu, increasing yield by 11.34% (highly significant) and 5.62% (highly significant) compared with the controls Zhou 903 and Zhe 733, respectively; in the 2002 continued trial, the average yield was 450.1 kg per mu, an increase of 6.92% (highly significant) compared with the control Jiayu 948, and a decrease of 1.53% (not significant) compared with the control Zhe 733. In the 2002 production trial, the average yield was 376.9 kg per mu, an increase of 1.55% compared with the control Zhe 733.

Key cultivation techniques: 1. Sowing at the right time: generally sow in early April, with 40 kg of seed per mu in the seedling field, and seedling age not exceeding 35 days; 2. Reasonable dense planting: transplanting spacing is 15 x 11.7 or 16.6 x 10 cm, with 3 to 4 grain seedlings per hill, and enough basic seedlings of 120,000 plants per mu; 3. Pest and disease control: pay attention to controlling the damage of rice blast, sheath blight, and rice planthoppers and other pests and diseases.