Introduction to the Characteristics and Traits of the Gangyou 177 Rice Variety

[Variety Name] Gangyou 177<基本情况>= Gangyou 177 (Gang 46A/Chenghui 177) is a medium indica late-maturing type, bred by the Crop Research Institute of the Sichuan Academy of Agricultural Sciences.

[Characteristics and Traits] According to the appraisal by the Rice and Rice Products Quality Supervision and Inspection Testing Center of the Ministry of Agriculture, Gangyou 177 has a brown rice rate of 80.6%, a milled rice rate of 72.8%, a head rice rate of 61.9%, a grain length of 6.2mm, a length-to-width ratio of 2.4, a chalkiness rate of 59%, a chalkiness degree of 6.0%, a transparency grade of 3, an alkali spreading value of 5.9, a gel consistency of 41mm, an amylose content of 22.7%, and a protein content of 92%.

Gangyou 177 is relatively resistant to rice blast. According to the appraisal by the Institute of Plant Protection and the Rice Research Institute of the Sichuan Academy of Agricultural Sciences, and the Rice Research Institute of Sichuan Agricultural University, Gangyou 177 has leaf blast grades of 2-6 and neck blast grades of 1-7; Shanyou 63 has leaf blast grades of 8-9 and neck blast grade 9.

The whole growth period of Gangyou 177 is 150d (average of 2a in the Sichuan provincial regional trial from 1998 to 1999), 1d longer than the control, with a plant height of 112.6cm, effective panicles of 2.3685 million/hm2, a panicle length of 24.8cm, an average of 159.6 grains per panicle, a seed-setting rate of 86.3%, and a 1000-grain weight of 27.7g. Gangyou 177 grows vigorously in the field, has a good plant and leaf type, moderate tillering ability, strong lodging resistance, and good color transition at maturity.

This combination participated in the variety comparison trial of the institute in 1996, with a yield of 8.16t/hm2, an increase of 8.15% over Shanyou 63; in 1997, a multi-point trial was conducted, with an average yield of 8.42t/hm2, an increase of 1.52% over the control Shanyou 63; from 1998 to 1999, it participated in the Sichuan provincial medium-late-maturing group regional trial, with an average yield of 8.28t/hm2 over 2a, an increase of 4.24% over the control Shanyou 63; in 1999, the average yield of the Sichuan provincial production trial at 6 sites was 8.99t/hm2, an increase of 5.45% over the control.

[Breeder] Crop Research Institute of the Sichuan Academy of Agricultural Sciences

[Region and Techniques] a) Sow early at the right time to cultivate strong seedlings with multiple tillers. In southeastern Sichuan, sowing in mid-to-late March is appropriate, and in northwestern Sichuan, early April. For seedling raising, open-field wet seedling raising, plastic-film wet seedling raising, two-stage seedling raising, and dry seedling raising are all acceptable. The seedling age is 35-40d. b) Proper close planting. Gangyou 177 has moderate tillering ability, a compact plant type, and upright flag leaves, and is suitable for close planting; the transplanting spacing is generally 20cm x 20cm. c) Reasonable fertilization. Nitrogen, phosphorus, and potassium should be reasonably combined and applied at the right time. The general principle is to apply heavy basal fertilizer, apply tillering fertilizer early, promote early and steady growth, and increase the rate of tillers forming panicles. For fields with medium fertility, the general pure nitrogen rate is 150-180kg per hectare, phosphate fertilizer 375-450kg, and potassium fertilizer 225-300kg. d) Timely prevention and control of pests and diseases. When Chenghui 177 is spring-sown in the Chengdu area, the period from sowing to initial heading is 105d, 4d shorter than Minghui 63, and the main stem has an average of 16.0 leaves, 0.5-1.0 fewer leaves than Minghui 63. The pollen amount is sufficient, pollen density is high, pollen shedding is good, and pollen vigor is strong; the flowering period is 10-12d, flowering time is relatively concentrated, and the peak flowering period on sunny days is 11:30-12:30. When Chenghui 177 is crossed with Gang 46A for seed production, the sowing interval is correspondingly shortened compared with producing Gangyou 12. For the remaining techniques, please refer to the seed production techniques for Gangyou 12.