BackgroundAnnexins are an evolutionarily conserved multigene family of calcium-dependent phospholipid binding proteins that play important roles in stress resistance and plant development. They have been relatively well characterized in model plants Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa), but nothing has been reported in hexaploid bread wheat (Triticum aestivum) and barely (Hordeum vulgare), which are the two most economically important plants.ResultsBased on available genomic and transcriptomic data, 25 and 11 putative annexin genes were found through in silico analysis in wheat and barley, respectively. Additionally, eight and 11 annexin genes were identified from the draft genome sequences of Triticum urartu and Aegilops tauschii, progenitor for the A and D genome of wheat, respectively. By phylogenetic analysis, annexins in these four species together with other monocots and eudicots were classified into six different orthologous groups. Pi values of each of Ann1–12 genes among T. aestivum, T. urartu, A. tauschii and H. vulgare species was very low, with the exception of Ann2 and Ann5 genes. Ann2 gene has been under positive selection, but Ann6 and Ann7 have been under purifying selection among the four species in their evolutionary histories. The nucleotide diversities of Ann1–12 genes in the four species were 0.52065, 0.59239, 0.60691 and 0.53421, respectively. No selective pressure was operated on annexin genes in the same species. Gene expression patterns obtained by real-time PCR and re-analyzing the public microarray data revealed differential temporal and spatial regulation of annexin genes in wheat under different abiotic stress conditions such as salinity, drought, cold and abscisic acid. Among those genes, TaAnn10 is specifically expressed in the anther but fails to be induced by low temperature in thermosensitive genic male sterile lines, suggesting that specific down-regulation of TaAnn10 is associated with conditional male sterility in wheat.ConclusionsThis study analyzed the size and composition of the annexin gene family in wheat and barley, and investigated differential tissue-specific and stress responsive expression profiles of the gene family in wheat. These results provided significant information for understanding the diverse roles of plant annexins and opened a new avenue for functional studies of cold induced male sterility in wheat.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-016-2750-y) contains supplementary material, which is available to authorized users.

BackgroundIn the flowering plants, many polyploid species complexes display evolutionary radiation. This could be facilitated by gene flow between otherwise separate evolutionary lineages in contact zones. Achillea collina is a widespread tetraploid species within the Achillea millefolium polyploid complex (Asteraceae-Anthemideae). It is morphologically intermediate between the relic diploids, A. setacea-2x in xeric and A. asplenifolia-2x in humid habitats, and often grows in close contact with either of them. By analyzing DNA sequences of two single-copy nuclear genes and the genomic AFLP data, we assess the allopolyploid origin of A. collina-4x from ancestors corresponding to A. setacea-2x and A. asplenifolia-2x, and the ongoing backcross introgression between these diploid progenitor and tetraploid progeny lineages.ResultsIn both the ncpGS and the PgiC gene tree, haplotype sequences of the diploid A. setacea-2x and A. asplenifolia-2x group into two clades corresponding to the two species, though lineage sorting seems incomplete for the PgiC gene. In contrast, A. collina-4x and its suspected backcross plants show homeologous gene copies: sequences from the same tetraploid individual plant are placed in both diploid clades. Semi-congruent splits of an AFLP Neighbor Net link not only A. collina-4x to both diploid species, but some 4x individuals in a polymorphic population with mixed ploidy levels to A. setacea-2x on one hand and to A. collina-4x on the other, indicating allopolyploid speciation as well as hybridization across ploidal levels.ConclusionsThe findings of this study clearly demonstrate the hybrid origin of Achillea collina-4x, the ongoing backcrossing between the diploid progenitor and their tetraploid progeny lineages. Such repeated hybridizations are likely the cause of the great genetic and phenotypic variation and ecological differentiation of the polyploid taxa in Achillea millefolium agg.

The photoperiod/temperature‐sensitive genic male sterile (P/TGMS) character is important for use of heterosis in hybrid wheat. In the present study, the fertility of 172 doubled haploid (DH) lines derived from the cross between a P/TGMS wheat line BS366 and a restorer wheat line Baiyu149 was investigated under both fertile and sterile environments during three cropping seasons. The phenotype was recorded based on the international seed setting rate. A total of 167 SSR and 1,278 SNP markers were used to construct a linkage map, with a total length of 3,748.94 cM and an average marker interval of 2.59 cM. Three QTLs were identified and designated as QF.bhw‐2DS, QF.bhw‐4BS and QF.bhw‐7Al, explaining 6.9%–12.8%, 19.7%–25.6% and 7.2%–8.8% of the phenotypic variances, respectively. These results lay a good basis for application of male sterility‐related molecular markers in improvement of two‐line hybrid wheat breeding system.

Aims: Root rot caused by Fusarium solani is an important disease seriously affecting the yield and quality of Astragalus membranaceus. Therefore, this study was performed to elucidate the antifungal activities and mechanisms of cinnamaldehyde treatment against F. solani and its control effect for A. membranaceus root rot. Methods and Results: Cinnamaldehyde significantly inhibited mycelial growth and spore germination of F. solani in dose-dependent, and the median effective concentration was 178.68 μl l −1 . Furthermore, scanning electron microscopy, propidium iodide staining, cell leakage experiments and ergosterol quantitation illuminated that cinnamaldehyde could alter the mycelial morphology, damage the plasma membrane and hinder the biosynthesis of ergosterol. Besides, cinnamaldehyde induced the generation of reactive oxygen species by synergistically upregulating the genes encoded subunits for NADPH oxidase. The disease suppression efficacy of 600 μl l −1 cinnamaldehyde against A. membranaceus root rot was 92.98 ± 6.08% (p < 0.05) under greenhouse conditions. Conclusions: This study proved that cinnamaldehyde could markedly inhibit the growth of F. solani in vitro and effectively suppress the occurrence of A. membranaceus root rot, perhaps by inducing oxidative damage, which results in the distortion of F. solani, and the destruction of cell membrane integrity and permeability. Significance and Impact of the Study: This study first explores the antifungal mechanisms of cinnamaldehyde against F. solani in vivo and vitro, thereby providing a promising candidate for disease biocontrol.