Detailed Introduction to the Rice Variety Chaoyou No. 1

[Basic Information]Chaoyou No. 1 (also called Jindao 1229) was bred by the Tianjin Rice Research Institute using three-line hybridisation and conventional breeding, with the parent combination (FH-541A/Jinzhu No. 1) F1 x 84-11.

[Characteristics]All indicators of this variety reach the national first-class standard for quality rice, among which crude protein (brown rice) is 10.32%, amylose (milled rice) 17.34%, brown rice rate 84%, milled rice rate 75.64%, head rice rate 74.34%, chalkiness rate and chalkiness degree both O (<5%, <1%), gel consistency 80mm, gelatinisation temperature (alkali spreading value) 7, transparency 0.83, length-to-width ratio 1.9, grain length 5.2mm, width 2.8mm. The rice is egg-white in colour, the grains are intact and glossy, not only crystal-clear in appearance but also fragrant and tasty when cooked. Cultivated as mid-season or late rice in the Beijing and Tianjin areas, the whole growth period is 145d, the yield per unit area is 7500-900Okg/hm2, plant height 110cm, large panicles and large grains, panicle length 22cm, average 116 grains per panicle, 1000-grain weight 26-27g, seed-setting rate 91%. Resistant to rice blast and rice false smut, yields higher than the control under medium fertility cultivation, and has good yield potential. Chaoyou No. 1 possesses the restorer gene and has very good restoring ability for japonica-type male sterile lines.

[Breeder]Tianjin Rice Research Institute

[Region and Techniques]Seedbed sowing rate 450-750kg/hm2; seedling age 30-4Od is suitable, sow in mid-May, transplant in mid-to-late June. After emergence, before the one-leaf stage, spray the seedbed evenly with 3kg/hm2 paclobutrazol mixed with 150Okg/hm2 water after draining, which can effectively control excessive growth and increase tillering. Apply topdressing early; for medium-fertility land use whole-layer fertilisation, apply 187.5kg/hm2 diammonium phosphate and 262.5kg/hm2 urea in the paddy field, then harrow the land to promote rapid fertiliser effect and early tillering. Apply the first topdressing 10-15d after transplanting, generally 150Kg/hm2 urea plus 4.5Kg/hm2 dimehypo. After 1Od apply another 75kg/hm2 urea to supplement weak seedlings. In dry or flood years the fertiliser amount may be increased or decreased by 20% as appropriate. Before sowing, seeds may be soaked with Jun Chong Qing for 2-3d; during the growth period pay attention to controlling diseases and pests such as the striped stem borer, leaf roller, rice planthopper and rice blast. When introduced southward this variety tends to have a shortened growth period, about 115-120d in the Luoyang area of Henan; it has a well-developed root system and strong drought resistance, and can be used for dry cultivation of rice, and can also be water-cultivated as wheat stubble rice; in Jianghua County, Hunan, it is 107d, with a seedling-throwing yield per unit area of 7200kg/hm2.

Apply base fertiliser of 225kg/hm2 urea and 75kg/hm2 diammonium phosphate, spread evenly and rotary till into the soil. At sowing the soil moisture should be sufficient; you may also apply emergence water, but the effect is not as good as the former. The sowing rate is 150kg/hm2, soak seeds with Jun Chong Qing for 48h, row spacing 25-3Ocm, sowing width 10cm. A sowing depth of 1-2cm is suitable, press down as you sow. Use oxadiazon to close and control weeds. Supplement water when dry in the early stage; from the tillering stage onward, change to flooded irrigation as much as possible. If dry-grown throughout the whole growth period, there is a risk of an extended growth period and failure to mature. All fertiliser should be applied before July 15, strictly avoiding excessive nitrogen in the later stage causing excessive vegetative growth.

Chaoyou No. 1 is suitable for planting in medium-fertility areas of Beijing, Tianjin, Hebei, Shandong, Henan, Shaanxi, Shanxi, Liaoning, Ningxia and other provinces and cities. In Beijing, Tianjin, Hebei and other areas it is mainly grown as mid-season rice or wheat stubble rice; in Liaoning and other areas it is widely planted as a quality rice variety; in Henan and other areas it is widely trialled as a dry-cultivated variety.