Introduction to the Characteristics of the Jingxiang 636 Rice Variety

I. Variety Origin

Bred in 1999 by the Institute of Crops, Beijing Academy of Agriculture and Forestry Sciences. The parent lines are: 91897-2A/T5850-1//h9418. Approved by Beijing in 2001.

II. Characteristics

A strongly aromatic rice variety. When grown as mid-season rice or as old seedlings for wheat-stubble rice in the Beijing plain region, the whole growth period is 150-155 days, plant height is 1.0-1.1 m, leaf color is green, tillering ability is medium, panicle type is relatively large, and awnless. The number of effective panicles per mu is 206,000, total grains per panicle is 141.0, filled grains 114.4, seed-setting rate 81.2%, and 1000-grain weight 23.4 g. The culm is relatively thick and has strong lodging resistance. Cold tolerance at the late stage is medium; under low-temperature conditions, grain filling is relatively slow, and there are relatively many empty grains at the panicle neck. It has a relatively high restoring degree (>70%) for IR24 cytoplasmic male sterile lines. The experimental yield can reach 450 kg per mu.

Moderately resistant to moderately susceptible to seedling blast and bacterial leaf blight, susceptible to bakanae disease, and shows light neck blast in the field.

Quality analysis: brown rice rate 83.0%, milled rice rate 74.3%, head milled rice rate 58.5%, chalkiness rate 12%, chalkiness degree 1.4%, amylose content 16.9%, protein content 8.5%. Compared with the original aromatic japonica varieties, the head milled rice rate is significantly increased, chalky grains are greatly reduced, and appearance quality is significantly improved; it can be marketed alone or used as an ingredient in high-quality blended rice.

III. Key Cultivation Techniques

1. Strictly disinfect seeds before sowing to prevent bakanae disease.

2. For mid-season rice cultivation, the suitable sowing period is early May, with transplanting around June 10; for wheat-stubble rice, sowing can be done from May 5-10, striving for early transplanting, with seedling age not exceeding 50 days. Sparse sowing is required to raise strong seedlings.

3. Transplanting spacing: row spacing about 25 cm, hill spacing 10-15 cm. Number of seedlings per hill: 2-3 seedlings for mid-season rice, 3-4 seedlings for wheat-stubble rice.

4. In management, focus on increasing the panicle-forming rate and seed-setting rate; in tiller fertilizer, increase the proportion of tiller-preserving fertilizer (40%); delay panicle fertilizer until before the meiosis stage, that is, do not let the mid-season drainage last too long, and refill water and apply topdressing 3-5 days before the flag leaf emerges, increasing or decreasing phosphorus and potassium fertilizer; in the late stage, stop irrigation 7 days later than for panicle-number-type varieties.

5. Pay attention to control of stem borer damage; for high-fertility fields, pay attention to monitoring rice blast and preventing neck blast.

IV. Suitable Planting Areas

Suitable for cultivation as single-season mid-season rice or wheat-stubble rice in the Beijing area, and as old seedlings in early-transplanted fields.