Genetic variation of temperature-regulated curd induction in cauliflower: elucidation of floral transition by genome-wide association mapping and gene expression analysis

Abstract

Cauliflower (Brassica oleracea var. botrytis) is a vernalization-responsive crop. High ambient temperatures delay harvest time. The elucidation of the genetic regulation of floral transition is highly interesting for a precise harvest scheduling and to ensure stable market supply. This study aims at genetic dissection of temperature-dependent curd induction in cauliflower by genome-wide association studies and gene expression analysis. To assess temperature-dependent curd induction, two greenhouse trials under distinct temperature regimes were conducted on a diversity panel consisting of 111 cauliflower commercial parent lines, genotyped with 14,385 SNPs. Broad phenotypic variation and high heritability (0.93) were observed for temperature-related curd induction within the cauliflower population. GWA mapping identified a total of 18 QTL localized on chromosomes O1, O2, O3, O4, O6, O8, and O9 for curding time under two distinct temperature regimes. Among those, several QTL are localized within regions of promising candidate flowering genes. Inferring population structure and genetic relatedness among the diversity set assigned three main genetic clusters. Linkage disequilibrium (LD) patterns estimated global LD extent of r2 = 0.06 and a maximum physical distance of 400 kb for genetic linkage. Transcriptional profiling of flowering genes FLOWERING LOCUS C (BoFLC) and VERNALIZATION 2 (BoVRN2) was performed, showing increased expression levels of BoVRN2 in genotypes with faster curding. However, functional relevance of BoVRN2 and BoFLC2 could not consistently be supported, which probably suggests to act facultative and/or might evidence for BoVRN2/BoFLC-independent mechanisms in temperature-regulated floral transition in cauliflower. Genetic insights in temperature-regulated curd induction can underpin genetically informed phenology models and benefit molecular breeding strategies toward the development of thermo-tolerant cultivars.

Effects of top-dressing nitrogen levels on the productivity of cauliflower

“…However, most vegetables traded are produced in other states. Thus, there is need for a greater dissemination of agronomic knowledge on the cultivation of cauliflowers, especially at a regional level (Matschegewski et al, 2015). Nitrogen fertilization is one of the production factors that may be analyzed aiming to encourage the production of cauliflower in the Great Dourados region.…”

The adaptive genomic landscape of beak morphology in Darwin's finches

“…). We focus on the results from the MLM (Q) contrasts more thoroughly than the GLM (PCA) analyses because PCA correction in systems can “overcorrect” by discounting significant differences between groups when natural stratifications correspond to true differences (Bordes et al., ; Li et al., ; Matschegewski et al., ; Savolainen, Lascoux, & Merilä, ; Wang et al., ; Wen, Boyse, Song, Cregan, & Wang, ).…”

Pembungaan dan Pembentukan Benih pada Beberapa Genotipe Kubis Bunga (Brassica oleracea var. botrytis L.)

“…Guo et al (2004) menyatakan bahwa suhu rendah sangat penting untuk menghasilkan bunga, tetapi tidak untuk pembentukan curd pada beberapa varietas kubis bunga. Penelitian mengenai pengaruh suhu terhadap pembentukan curd telah dilakukan, diantaranya Gomies et al (2012), Matschegewski et al (2015), dan Hasan et al (2016), tetapi penelitian terkait pembentukan benih pada kubis bunga masih kurang. Penelitian ini bertujuan untuk mengidentifikasi pengaruh perbedan lokasi penanaman, yaitu dataran tinggi dan dataran rendah terhadap pembentukan benih beberapa genotipe kubis bunga.…”