Dose‐dependent interactions between two loci trigger altered shoot growth in BG‐5 × Krotzenburg‐0 (Kro‐0) hybrids of Arabidopsis thaliana

Abstract

Hybrids occasionally exhibit genetic interactions resulting in reduced fitness in comparison to their parents. Studies of Arabidopsis thaliana have highlighted the role of immune conflicts, but less is known about the role of other factors in hybrid incompatibility in plants. Here, we present a new hybrid incompatibility phenomenon in this species. We have characterized a new case of F hybrid incompatibility from a cross between the A. thaliana accessions Krotzenburg-0 (Kro-0) and BG-5, by conducting transcript, metabolite and hormone analyses, and identified the causal loci through genetic mapping. The F hybrids showed arrested growth of the main stem, altered shoot architecture, and altered concentrations of hormones in comparison to parents. The F phenotype could be rescued in a developmental-stage-dependent manner by shifting to a higher growth temperature. These F phenotypes were linked to two loci, one on chromosome 2 and one on chromosome 3. The F generation segregated plants with more severe phenotypes which were linked to the same loci as those in the F . This study provides novel insights into how previously unknown mechanisms controlling shoot branching and stem growth can result in hybrid incompatibility.

Metabolomics in the Context of Plant Natural Products Research: From Sample Preparation to Metabolite Analysis

“…Liquid-liquid extraction using chloroform/methanol/water have been used for the analysis of lipids and polar metabolites [46][47][48][49]. As a cleaner and safer solvent, methyl tert-butyl ether (MTBE) has also been used as an alternative to chloroform for liquid-liquid extraction [50], particularly for the recovery of metabolites and lipids from bacterial, plant, algal, flies, and diverse mammalian samples [41,42,[51][52][53][54][55][56][57][58][59][60]. The use of isotope-labeled internal standards during sample preparation is recommended to assess matrix effects [39,61].…”

An Ultra High-DensityArabidopsis thalianaCrossover Map That Refines the Influences of Structural Variation and Epigenetic Features

“…Smaller-scale structural variants (SVs) of different types have also been implicated in the suppression of meiotic recombination. For example, a 70-kb transposition on Arabidopsis thaliana chromosome 3 showed extreme local suppression of recombination at the excision site in an F 2 cross between accessions BG-5 and Kro-0 (Alhajturki et al 2018). This type of rearrangement creates an insertion/deletion (indel) polymorphism at both the original locus and the new location.…”

Diverse paths to hybrid incompatibility in Arabidopsis

“…Similar phenotypes have also been observed among crosses between Shahdara and different Lagodechi accessions (Figure b). In another reported case, the F 1 hybrid between A. thaliana Krotzenburg‐0 × BG‐5 shows an altered shoot architecture and segregation of F 2 hybrid breakdown associated with a severe loss of fertility (Alhajturki et al ., ). Two loci were further shown to be linked to the phenotypes, from which neither is known to be associated with shoot architecture in plants (Alhajturki et al ., ).…”

“…In another reported case, the F 1 hybrid between A. thaliana Krotzenburg‐0 × BG‐5 shows an altered shoot architecture and segregation of F 2 hybrid breakdown associated with a severe loss of fertility (Alhajturki et al ., ). Two loci were further shown to be linked to the phenotypes, from which neither is known to be associated with shoot architecture in plants (Alhajturki et al ., ). Moreover, hybrid breakdown was observed in the F 2 generation of a cross between A. thaliana accessions Shahdara × Lövvik‐5 (Plötner et al ., ).…”

“…In addition to hybrid necrosis, the shoot‐branching phenotype in BG‐5 × Krotzenburg‐0 hybrids is also temperature dependent (Alhajturki et al ., ). In this case, the effect of temperature on stem growth was induced only at the time of flowering.…”