GUTIÉRREZ-LARRUSCAIN, David, KRÜGER, Manuela, ABEYAWARDANA, Oushadee A.J., BELZ, Claudia, DOBREV, Petre, VAŇKOVÁ, Radomíra, ELIÁŠOVÁ, Kateřina, VONDRÁKOVÁ, Zuzana, JUŘÍČEK, Miloslav, ŠTORCHOVÁ, Helena. Contrasting gene expression patterns during floral induction in two Chenopodium ficifolium genotypes reveal putative flowering regulators. Plant Signaling & Behavior. 2025, 20(2), e2486083. ISSN 1559-2316. E-ISSN 1559-2324

Chenopodium ficifolium is a close diploid relative of the tetraploid crop Chenopodium quinoa. Owing to its reproducible germination and seedling development, it becomes a promising model for studying floral induction, providing a basis for the comparison with C. quinoa. Two C. ficifolium genotypes differ in photoperiodic requirement: C. ficifolium 283 accelerates flowering under long days, whereas C. ficifolium 459 flowers earlier under short days. This study conducted a comprehensive transcriptomic and hormonomic analysis of floral induction in the long-day C. ficifolium 283 and compared the findings to previous experiments with the short-day C. ficifolium. Phytohormone concentrations and gene expression profiles during floral induction were largely similar between the two genotypes. However, a subset of genes exhibited contrasting expression patterns, aligning with the genotypes' differing photoperiodic requirements. These genes, predominantly homologs of flowering-related genes in Arabidopsis thaliana, were activated under long days in C. ficifolium 283 and under short days in C. ficifolium 459. Notably, the contrasting expression of the FLOWERING LOCUS T-LIKE 2-1 gene, which was previously shown to induce precocious flowering in A. thaliana, confirmed its role as a floral activator, despite its low expression levels.