QTL detection for grain shape and fine mapping of two novel locus and .

UNLABELLED

Rice grain size and grain weight, which have a great influence on rice quality and yield, are complex quantitative traits that are mediated by grain length (GL), grain width (GW), length-to-width ratio (LWR), and grain thickness (GT). In this study, the BCF and BCF populations derived from a cross between two rice varieties, Guangzhan 63-4S (GZ63-4S) and Dodda, were used to locate quantitative trait loci (QTL) related to grain size. A total of 30 QTL associated with GL, GW and LWR were detected, of which six QTL were scanned repeatedly in both populations. Two QTL, and , were selected for genetic effect validation and were subsequently fine mapped to 2.359 kb and 176 kb, respectively. (known as ), which encoding an ent-beyerene synthase and as the only gene found in 2.359 kb interval, was proposed to be the candidate for . Moreover, the grains of homozygous mutant plants generated by the CRISPR-Cas9 system became shorter and wider. In addition, the allele from GZ63-4S contributes to the increase of yield per plant. Our study not only laid the foundation for further functional study of and map-based cloning of , but also provided genetic resources for the development of high yield and good quality rice varieties.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11032-024-01502-8.