Detailed introduction to rice variety K404

(1) Variety origin: This is a new hybrid early rice combination developed by the Rice and Sorghum Research Institute of the Sichuan Academy of Agricultural Sciences by crossing K1A with the introduced early rice restorer line 404.

(2) Characteristics: This combination is cold-tolerant at the seedling stage, with dark green leaves and a moderately compact plant type; the full growth period is 115 days; plant height is 91 cm, with strong tillering ability and a relatively high rate of productive tillers; the effective panicles per mu are 210,000-230,000, panicle length is 19-20 cm, about 100 grains per panicle, seed-setting rate above 75%, and 1000-grain weight 28 g; rice milling and appearance quality are superior to the control; moderately resistant to bacterial leaf blight and rice blast.

(3) Yield performance: In the 1995-1996 Sichuan provincial regional trial, the average yield per mu was 483.14 kg, an increase of 9.13% over the control Luhongzao No. 1. In the 1997-1998 national regional trial, the pooled average yield per mu was 471.1 kg, an increase of 10.1% over the control Zhe 733; in the 1998 national production trial, the average yield per mu was 491.1 kg, an increase of 8.1% over the control Weiyou 402. In production demonstrations, the usual yield per mu is 480-510 kg.

(4) Suitable planting areas: Suitable for cultivation as late-maturing early rice.