Auxin was involved in earlier flowering under experimental far-red light in rapid-cycling Brassica rapa

Non-heading Chinese cabbage ( Brassica campestris ssp. chinensis Makino) is a biennial vegetable that is commonly cultivated in China. To enhance breeding efficiency, various techniques for promoting flowering are being explored. In this study, a bolting resistant cultivar (‘Mei Hui’) were chosen and exposed to artificial blue and far-red light. Flowering time was recorded and RNA-sequencing coupled with quantitative PCR analyses were performed. The results showed that artificial blue and far-red complex light effectively promoted flowering. The regulation of flowering involved significant contributions from endogenous hormones. Here we identified 3953 differently expressed genes (DEGs) and hormone/polysaccharide metabolism pathway was enriched through GO enrichment analysis. Particularly important, auxin metabolic and biosynthesis pathway in the regulation of flowering were further studied. Among these DEGs, some major DEGs were screened and their expression was analyzed. The present finding supported that GH3 encoding genes BraA09g010220. 3C, BraA09g054360.3C, BraA02g004780. 3C, BraA09g002530.3C, BraA01g001510.3C, BraA03g053600.3C and BraA06g004320.3C , YUCCA8 encoding genes BraA08g018860.3C , IAA encoding genes BraA03g040670.3C, BraA01g005780.3C, BraA03g040660.3C, BraA05g030630.3C, BraA05g040420.3C and BraA08g010620.3C , PIN encoding genes BraA07g014360.3C, BraA07g029730.3C and BraA07g035620.3C , ABCB encoding genes BraA07g029880.3C, BraA09g020340.3C and BraA09g036730.3C , were emerged as candidate genes potentially involved in regulating flowering in pak choi. Our team is now working to further elucidate the functions of these genes.