Breeding of High-quality, High-yield, Early-maturing Hybrid Rice Huangyou Yuehesimiao

  Objective   To fully explore the potential of existing resources, an early-maturing hybrid rice CMS line with much desirable qualities was bred.

  Method   Luxiang 90B as the female parent and the high-quality early-maturing traditional Jiafuzhan as the male parent were applied for the hybridization. To save time, a part of the self-crossing process was conducted in the warmer southern province of Hainan, instead of Fujian, in winter. A blast resistance test was performed at a tea plantation in Shanghang. Hybrids showing the target traits of early maturation, large grains, high quality, and disease resistance were selected to backcross with II -32A for several generations. The final combined line was then crossed with the traditional restorer line Yuehesimiao to yield a 3-line hybrid indica rice for submission to the comparative trials held in different provinces.

  Result  An early-maturing, high-quality, strong combining ability CMS line, Huangda A, was obtained in 2013 to be crossed with Yuehesimiao resulting in a new 3-line hybrid indica rice named Huangyou Yuehesimiao in spring 2016. During 2016–2017, the newly bred rice was submitted to the trials in Hainan and Jiangxi in addition to Fujian for performance evaluation. Subsequently, in 2018–2020, it participated in the trials for screening, regional competition, and production of early-season rice in Fujian as well as early-maturing, late-season indica rice in the middle and lower reaches of Yangtze River to be critically examined in regard to growth period, yield, blast resistance, grain quality, and adaptability of the rice varieties. In the Hainan, Jiangxi, and Fujian trials, Huangyou Yuehesimiao delivered an average yield of more than 8 100.00 kg·hm⁻², which was a 4.33% to 18.76% higher than that of the reference variety. In the screening, regional, and production trials on early-season rice, it showed the average yields of 8 014.5 kg·hm⁻², 8 003.70 kg·hm⁻², and 7 444.65 kg·hm⁻², respectively, representing increases of 4.80%, 10.93%, and 8.26%, respectively, in comparison to that of T78 You 2155. Meanwhile, in the regional and production trials on early-maturing, late-season rice in the middle and lower reaches of Yangtze River, the average yields were 9 761.25 kg hm⁻² and 8 838.45 kg·hm⁻², respectively, with 4.18% and 3.54% increases, respectively, as compared to Wuyou 308. The new variety was certified by the Fujian Province Crop Variety Approval Committee in 2020 and by the National Crop Variety Approval Committee in 2021.

  Conclusion   Huangyou Yuehesimiao was a high-quality, high- and stable-yield, blast resistant hybrid rice suitable for either early or late season cropping. The grain quality met the national standard for Grade-1 early rice and Grade-3 late rice as set by the Ministry of Agriculture. Consequently. Consequently, it was deemed appropriate for early and late-season double cropping rice cultivation in Fujian or areas such as the middle and lower reaches of the Yangtze River.