Introduction to the Rice Variety Boyou Gan 28

[Basic Information] Boyou Gan 28 (Boyou 752) is a medium-late, late-maturing combination bred by the Rice Research Institute of the Jiangxi Academy of Agricultural Sciences by crossing the male-sterile line Bo A with the self-selected restorer line 752.

In spring in Hainan, test crosses were made using the Guangxi male-sterile line Bo A with the strong restorer line 752 (selected from 26 Zhai Zao/BG910) bred by this research group; in the autumn of the same year, a heterosis comparison trial was conducted in the institute's experimental field. The result was outstanding yield, with a measured yield of 102 t/hm2, 9.9% higher than Shanyou 63.

In 1996, Boyou Gan 28 participated in the Jiangxi Provincial Late Rice Regional Trial, with an average yield of 6.07 t/hm2, 2.62% lower than Shanyou 10. In the 1997 provincial regional trial, due to the effects of heavy rain and low temperature, the yield was 5.6 t/hm2, 12.05% lower than Shanyou 63.

[Characteristics] Boyou Gan 28 has a plant height of 110 cm, a compact plant type, relatively narrow leaves, erect flag leaves and a good light-receiving posture; strong tillering ability, uniform heading, a well-developed root system, tolerance to fertilizer and resistance to lodging, a high fertilizer requirement, and good color retention at the late stage; strong heterosis with large panicles and many grains, a panicle length of 24-26 cm, 8-10 effective panicles per plant, 160 total grains per panicle, a seed-setting rate of 88.7%, and a 1000-grain weight of 26 g.

The whole growth period of Boyou Gan 28 is 150-155 d as mid-season rice and 140 d as double-cropping late rice, 5-7 d longer than Shanyou 63. In central-southern Jiangxi and western Jiangxi, it can be planted as mid-season rice and double-cropping late rice; in northern Jiangxi, it is suitable for planting as mid-season rice. This combination has great flexibility in seedling age, and when planted as double-cropping late rice, there is no premature heading even when the seedling age exceeds 40 d.

Boyou Gan 28 showed high yield in trial planting and demonstrations. In 1996, Pingxiang City demonstrated 20 hm2, with yield verification on 1.5 hm2, and an average yield of 8.67 t/km2, 9.9% higher than Shanyou 63. In 1997, Yuannan Township, Luxi County, trial-planted 32 hm2, with an average yield of 8.4 t/hm2 and a maximum yield of 10.37 t/hm2. According to 1997 statistics from the Jiangxi Provincial Seed Station on extensively promoted hybrid rice combinations across the province, Boyou Gan 28 had an average yield of 7.65 t/hm2, 11.5% higher than Shanyou 63. In 1999, it was listed by the Jiangxi Provincial Department of Agriculture as a main single-cropping late rice combination. This combination has been demonstrated and promoted on 100,000 hm2 in Jiangxi, Guangxi, Hainan and Guangdong.

According to rice quality analysis by the Crop Research Institute of Jiangxi Agricultural University, Boyou Gan 28 has a brown rice rate of 79.9%, a milled rice rate of 70.3%, a head rice rate of 50.8%, a grain length of 6 mm, a length-to-width ratio of 2.5, a chalky grain rate of 42%, a chalkiness degree of 10.7%, an alkali spreading value of 4.9 grade, a gel consistency of 34.5 mm, and an amylose content of 16.6%. Most indicators reach the Ministry-issued second-grade high-quality rice standard. It tastes good, soft and pleasant. Its appearance quality and eating quality are superior to those of Shanyou 63 and Shanyou 10.

After many years of planting, this combination has not had rice blast or bacterial leaf blight occur in the field, showing good field resistance.

[Breeder] Rice Research Institute of the Jiangxi Academy of Agricultural Sciences

[Region and Techniques] Sow at the appropriate time, and raise strong seedlings with sparse sowing and sufficient fertilizer. When cultivating Boyou Gan 28 as double-cropping late rice, sow from June 1 to 4, with a sowing rate of 112.5 kg/hm2 and a field seed rate of 12-15 kg/hm2; the optimal seedling age is 40-45 d, and the maximum should not exceed 50 d. The seedling field should be given sufficient basal fertilizer, and sowing should be uniform and sparse. Apply paclobutrazol at the 1-leaf 1-heart stage to promote early tillering, so that each plant carries 3-4 tillers at transplanting.

Reasonable close planting. It requires 240,000-270,000 hills/hm2, with 1-2 grain seedlings per hill, striving for 2.25 million-2.55 million/hm2 effective panicles.

Scientific fertilization and water management. Boyou Gan 28 is tolerant to fertilizer and resistant to lodging, and has great yield-increasing potential under high-fertility conditions. It requires 160-180 kg of pure nitrogen per hectare. In the field, apply sufficient basal fertilizer, topdress early, and skillfully apply grain-filling fertilizer. Water management should combine drying and wetting, and strictly prevent premature water cutoff at the late stage.

Pay attention to the control of diseases and insect pests to ensure high and stable yield.

Key points of seed production techniques: correctly arrange the sowing interval. For local autumn seed production, the sowing interval between parents is 16-18 d, with a leaf difference of 4.8-5.0 leaves; for Hainan spring seed production, the sowing interval is 18-20 d, with a leaf difference of 5 leaves. The leaf difference should be taken as the standard. Raise strong seedlings and transplant at the appropriate time. The seedling field should be leveled and finely prepared, with sufficient basal fertilizer; the seedling age generally should not exceed 20 d, and the leaf age should not exceed 5.5 leaves. For other seed production techniques, refer to Boyou Gui 99.