Abstract:
Objective A new high-yield, high-quality, aromatic inbred rice variety was generated using an introgression line derived from Oryza minuta for the seed industry.
Method The O. minuta introgression line Guihui 110 as the female parent and the aromatic genotype OsBADH2-carrying F1 hybrid of Huazhan/K08 as the male parent were used in the hybridization. After emasculation, two rounds of backcrossing with Guihui 110 as the recurrent parent were performed followed by multiple generations of inbreeding with molecular marker-assisted selection. The secured rice underwent generational verifications on grain quality, yield, aroma, and resistance at trials prior to receiving official certification.
Result In the early cropping season of 2019, the newly bred high-yield, high-quality aromatic Nafeng 2 that carried the desirable aroma gene OsBADH2 was selected from the BC2F6 population. It displayed outstanding comprehensive agronomic traits in the field trials. And in the subsequent two-year regional trials from 2022 to 2023, it achieved an average yield of 7.28 t·hm−2, with a 5.90% increase over that of the reference Liushayouzhan 202 and increases at all trial sites. At the 2023 production trial, it delivered an average yield of 6.33 t·hm−2, which was 5.81% higher than that of reference and increases at all sites, with zero lodging. The grain quality of Nafeng 2 met the national standard for first-class high-quality edible medium-grain indica rice, with a high score of 76 on aroma. It was approved by the Guangxi Crop Variety Approval Committee in 2024 with the certificate number of “Guishendao 2024127”.
Conclusion The certified Nafeng 2 was characterized with vigorous growth, thick and strong stems, compact plant architecture, large panicles with numerous grains, desirable grain ripening color at late stage, high yield, superior grain and eating quality, and strong lodging resistance.