Identification of QTLs associated with curd architecture in cauliflower

Abstract

Background: Curd architecture is one of the most important characters determining the curd morphology of cauliflower. However, the genetic mechanism dissection of this complex trait at molecular level is lacking. Genes/ QTLs responsible for the morphological differences between present-day loose-curd and compact-curd cauliflower haven't been well revealed. Results: Herein, by using a common compact-curd parent and two loose-curd parents, we developed two double haploid (DH) populations including 122 and 79 lines, respectively. For each population, we decomposed the curd architecture concept into four parameters (basal diameter, stalk length, stalk angle and curd solidity), and collected corresponding phenotypic data for each parameter across two environments. The Kosambi function and composite interval mapping algorithm were conducted to construct the linkage map and analyze the QTLs associated with curd architecture parameters. A total of 20 QTLs were detected with the minimum likelihood of odd (LOD) values ranging from 2.61 to 8.38 and the percentage of the phenotypic variance explained by each QTL (PVE) varying between 7.69 and 25.10%. Of these, two QTLs controlling stalk length (qSL.C6-1, qSL.C6-2) and two QTLs controlling curd solidity (qCS.C6-1 and qCS.C6-2) were steadily expressed in both environments. Further, qSL.C6-1, qSL.C6-2, qCS.C6-1 and qCS.C6-4 fell into the same chromosomal region of the reference genome, indicating that these loci are involved in pleiotropic effects or are tightly linked. Conclusion: The current study identified a series of QTLs associated with curd architecture parameters, which might contribute essentially to the formation of present-day loose-curd cauliflower that is widely cultivated in China. These results may pave the way for intensive deciphering the molecular mechanisms of curd development and for marker-assisted selection of curd morphology in cauliflower breeding.

A High-Resolution Linkage Map Construction and QTL Analysis for Morphological Traits in Anthurium (Anthurium andraeanum Linden)

“…The result that these QTLs associated with different traits were co-located might be attributed to one same QTL, a gene multi-effect, or two QTLs closely linked, therefore leading to the correlation among morphological traits. Similar colocalizing QTLs were also observed in other plants such as prunus mume [43,44], rice [45], wheat [46,47], sesame [48], cauliflower [49], barley, and so on [50]. However, whether the co-localized QTLs are single-gene with pleiotropism or are just closely linked but distinct genes in our results remains to be further studied.…”

Nanobiochar Application in Combination with Mulching Improves Metabolites and Curd Quality Traits in Cauliflower

“…Overall, these results can be explained based on NBC-mediated improvements in physio-biochemical traits and the presence of growth-promoting substances. Curd architecture is mainly determined by polygenetic factors, although also influenced by environmental conditions such as nutrient availability [70]. Metwaly [71] reported that the P and K influenced the curd morphological traits and curd compactness.…”

Identification of Loci for Four Important Agronomic Traits in Loose-Curd Cauliflower Based on Genome-Wide Association Studies

“…To facilitate the breeding of cauliflower, some studies have tried to detect genomic loci for its agronomic traits. Zhao et al [10] performed a mapping of quantitative trait loci (QTLs) by using two double-haploid (DH) populations, and they identified 20 QTLs for curd architecture, including stalk length (qSL.C6-1, qSL.C6-2) and curd solidity (qCS.C6-1 and qCS.C6-2). Hasan et al [11] detected QTL regions that were involved in the temperaturedependent time to curd induction, on chromosomes C06 and C09.…”