Origin and de novo domestication of sweet orange.

Sweet orange is cultivated worldwide but suffers from various devastating diseases because of its monogenetic background. The elucidation of the origin of a crop facilitates the domestication of new crops that may better cope with new challenges. Here we collected and sequenced 226 citrus accessions and assembled telomere-to-telomere phased diploid genomes of sweet orange and sour orange.

Somatic variations in the meiosis-specific gene CrMER3 confer seedlessness in a citrus bud sport.

Seedlessness is a most valuable trait in fruit crops for fresh consumption and processing. The mutations in essential meiosis genes are known to confer sterility and seed abortion in plants. However, defects in meiosis have rarely been reported in fruit crops.

miR171-targeted SCARECROW-LIKE genes CsSCL2 and CsSCL3 regulate somatic embryogenesis in citrus.

Somatic embryogenesis (SE) is a key regeneration pathway in various biotechnology approaches to crop improvement, especially for economically important perennial woody crops like citrus. However, maintenance of SE capability has long been a challenge and becomes a bottleneck in biotechnology-facilitated plant improvement. In the embryogenic callus (EC) of citrus, we identified 2 csi-miR171c-targeted SCARECROW-LIKE genes CsSCL2 and CsSCL3 (CsSCL2/3), which exert positive feedback regulation on csi-miR171c expression.