Inheritance of Annual Flowering in Brassica oleracea

Abstract

Segregation for annual vs. biennial flowering habit was observed in F2 progenies from crosses of early and late-maturing broccoli (Brassica oleracea L. Italica Group) inbred lines with cabbage (B. oleracea L. Capitata Group), kohlrabi (B. oleracea L. Gongyloides Group), collards (B. oleracea L. Acephala Group), kale (B. oleracea L. Acephala Group), and brussels sprouts (B. oleracea L. Gemmifera Group). F, progenies were usually completely annual. F2 progenies from crosses involving late broccoli contained two to five times as many biennials as F2 progenies from early broccoli crosses. Maturity factors carried by the biennial parents also appeared to affect expression of flowering habit. Annual habit is dominant over biennial and is controlled by several major genes with a strong effect of modifiers from both the annual and biennial parent. Time of heading of annual plants in F2 progenies appeared to be controlled by quantitative, mainly additive, factors. Distribution of heading dates for the F1 and annual broccoli parents showed a large environmental or cultural effect. It appears that the biennial parents, especially brussels sprouts and collards, contributed strong factors for late maturity.

Advancing utilization of diverse global carrot (Daucus carota L.) germplasm with flowering habit trait ontology

“…This carrot flowering ontology attempts to capture this diverse range of flowering variation with additional categories based on perceived usefulness. High broad sense heritability for flowering reported in our study is similar to estimations in other carrot germplasm collections (Manikanta et al, 2018), and consistent with documented simple inheritance of flowering habit in carrot, with two recessive loci conditioning biennial habit (Alessandro & Galmarini, 2007;Alessandro et al, 2013;Wohlfeiler et al, 2019), and in other plants such as Arabidopsis (Michaels & Amasino, 2000), sugar beet (Abe et al, 1997), celery (Quiros et al, 1987), brassicas (Pelofske & Baggett, 1979;Baggett & Kean, 1989), and lettuce (Whitaker, 1944). Our study also agrees with Solberg and Yndgaard (2015), that the diversity within accessions for flowering habit is not well captured by the GRIN-global classification the genebanks' information system, where accessions are categorized as biennial, annual, or mixture.…”