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Membrane-bound fatty acid desaturase (FAD) gene family plays crucial roles in regulation of fatty acid (FA) compositions in plants. Sunflower (Helianthus annuus L.) is an important oilseed crop in the world; however, no comprehensive study on exploring the role of FAD family in relation to stress tolerance in sunflower has been performed yet. In this study, we identified 40 putative FAD genes in H. annuus (HaFAD), which were unevenly distributed across 13 of the total 17 chromosomes. Phylogenetic analysis indicated that HaFAD genes were divided into four subfamilies, as supported by highly conserved gene structures and motifs. Collinearity analysis showed that tandem duplication events played a crucial role in the expansion of HaFAD gene family. In addition, tissue-specific expression showed that 32 HaFAD genes were widely expressed in various tissues or organs of sunflower. Furthermore, qRT-PCR results revealed significant expression changes of HaFAD genes in response to abiotic (cadmium, drought) and biotic (Orobanche cumana) stresses, suggesting their important functions in response to different stresses. Therefore, our results provide insights into HaFAD gene family in response to different stresses, and some specific up-regulated genes such as HaFAD3.2 , HaADS8 , HaFAD2.1 , and HaADS9 would be the potential candidate genes for the sunflower tolerance breeding. • A total of 40 FAD genes were identified in Helianthus annuus L. • Genome-wide characterization of FAD family was conducted in sunflower. • The heatmap of 32 HaFAD s in ten different tissues and organs was established. • 33 selected HaFAD s were differentially expressed under biotic and abiotic stresses. [ABSTRACT FROM AUTHOR]

• A total of 119 WRKY genes were identified in Helianthus annuus L. • WRKYs present genetic diversity among oil crops. • Segmental and tandem duplications contribute to the expansion of sunflower WRKYs. • Expression analysis shows neo- or subfunctionalization after WRKY duplications. • Some HaWRKY genes play critical roles response to biotic and abiotic stresses. WRKY proteins constitute a large family of transcription factors that play important roles in many aspects of physiological processes and adaptation to environmental challenge. Although previous studies have identified and characterized WRKY genes from sunflower (Helianthus annuus L.) expressed sequence tag and genomic databases, the phylogenetic diversity of WRKY repertoires of oil crop species and the responses of sunflower WRKY proteins to various stressors have not been elucidated. In this study, a total of 860 WRKY members from seven oil crop species, namely, sunflower, sesame, castor bean, soybean, canola, Arachis duranensis , and Arachis ipaensis , were subjected to comparative genomic analysis. Genetic diversity within the WRKY family among these oil crop species was revealed through pairwise comparisons of orthologous groups and phylogenetic analysis. Sequence features and phylogenetic analysis revealed that the WRKY genes of oil crop species belong to well-defined groups or subgroups, and different oil plant species exhibit obvious expansion or loss to different degrees. One hundred nineteen sunflower WRKY (HaWRKY) genes were found to be unevenly distributed across each chromosome. Segmental and tandem duplications contributed to the expansion of group II and III WRKY genes in sunflower, respectively. The duplicated genes generally exhibit divergent expression patterns, which may indicate that neofunctionalization or subfunctionalization of these genes tends to occur after duplication. Moreover, expression profiles derived from transcriptomic data exhibited distinct expression patterns of HaWRKY genes in various tissues and in response to different stress treatments, including hormone treatments, salt and drought stress, infection by the fungus Verticillium dahliae , and colonization by the fungus Rhizoglomus irregulare. According to these results, WRKY genes may be involved in the strong adaptability of sunflower to various environments, thereby contributing to the importance of sunflower as a widely cultivated oil resource. This systematic analysis provides a foundation for further functional characterization of WRKY genes among oil crop species for the improvement of stress resistance. [ABSTRACT FROM AUTHOR]

• A total of 722 metabolites were identified in the seeds of eight buckwheat varieties. • 84 key active ingredients and 78 active pharmaceutical ingredients were identified. • Tartary and common buckwheat differ in metabolite composition. • 155 and 48 biomarkers were identified in Tartary and common buckwheat, respectively. • Tartary buckwheat is a promising source with higher health-promoting value. Tartary buckwheat has higher health-promoting value than common buckwheat. However, the related metabolites information except flavonoids is largely deficient. Here, we compared the seed metabolomes of the two species using a UHPLC-QqQ-MS-based metabolomics approach. In total, 722 metabolites were obtained, of which 84 and 78 were identified as the key active ingredients of Traditional Chinese Medicines and the active pharmaceutical ingredients for six major diseases-resistance, respectively. Comparative analysis showed there were obviously difference in metabolic profiles between the two buckwheat species, and further found 61 flavonoids and 94 non-flavonoids metabolites displayed significantly higher contents (≥2 fold) in Tartary buckwheat than in common buckwheat. Our results suggest that Tartary and common buckwheat seeds are rich in metabolites beneficial to human health, and non-flavonoids metabolites also contributed to Tartary buckwheat's higher health-promoting value than common buckwheat. This study provides valuable information for the development of new functional foods of Tartary buckwheat. [ABSTRACT FROM AUTHOR]

• The thermal degradation of Cy3G in nitrogen over 30–600 °C occurs in three steps. • The phenols and furans in the pyrolysis products of Cy3G are toxic to some extent. • For safety, anthocyanin-rich foods should be processed at below 100 °C. • High-temperature processing of anthocyanin-rich foods produces toxic substances. The thermal degradation behavior of cyanidin-3-O-gluoside (Cy3G) in nitrogen and air was studied using thermogravimetric analysis (TGA), thermogravimetry–Fourier transform infrared spectroscopy (TG-FTIR) and pyrolysis–gas chromatography/mass spectrometry (Py-GCMS). The results show that the thermal degradation of Cy3G in nitrogen and in air can be divided into three steps. The total degradation rate was 63.09% in nitrogen and 99.42% in air, and the total activation energy (E a) was 65.85 and 80.98 kJ·mol−1, respectively. The TG-FTIR analysis showed that Cy3G is significantly decomposed at 200–300 °C. The Py-GCMS analysis shows that the first step in the thermal degradation of Cy3G in nitrogen is the cleavage of glycosidic bonds to give cyanidin and glucoside. The glucoside and cyanidin then degrade further to give mainly low molecular weight compounds, together with furan derivatives, pyran derivatives and aromatic compounds. The phenols and furans found in the pyrolysis products are known to have a degree of toxicity. [ABSTRACT FROM AUTHOR]

CONSTANS-like (COL) genes play crucial roles in the regulation of photoperiodic flowering and responses to biotic and abiotic stresses; however, COL genes in sunflower (HaCOL) have not been extensively studied. In the present study, we identified 22 putative HaCOL genes in the whole genome sequence of sunflower, which were unevenly distributed on 10 chromosomes. The phylogenetic analysis showed that the HaCOLs could be divided into three well-defined groups (groups I, II and III). Group III had the highest number of COL genes among the three tested monocots, while the highest number of COL genes were observed in group I among the five tested dicots. Among all eight species, group II had the fewest COL family members. Segmental duplications contributed greatly to the expansion of this gene family. Furthermore, 11 tissue expression profiles of 22 HaCOL genes were analyzed through RNA-seq, which displayed their tissue-specific expression profiles. In addition, the expression levels of these HaCOL genes were analyzed under hormone, cadmium (Cd), heat, and drought stresses, and the results showed that HaCOL3 , HaCOL6 , and HaCOL19 were more sensitive than other HaCOLs to certain abiotic stresses. Moreover, the duplicated genes conferred important neofunctionalization in response to abiotic stresses. On the basis of our findings, we speculate that this conserved, duplicated and neofunctionalized COL gene family may play pivotal roles in the adaptation of sunflower to adverse environments. • A total of 22 putative CONSTANS-like genes identified in sunflower genome. • Sunflower CONSTANS-like genes could be divided into three well defined groups. • Segmental duplications contribute greatly to the expansion of this gene family. • Duplicated genes confer their novel functions in response to abiotic stresses. • The neofunctionalized sunflower COLs involved in environmental adaptation. [ABSTRACT FROM AUTHOR]

• Root flavonoid contents were higher in triennial S. flavescens than biennial S. flavescens. • Taproot and lateral root expression profiles were clustered by cultivation period. • Genes involved in flavonoid biosynthesis in S. flavescens were identified. • Transcription factors are involved in flavonoid biosynthesis in S. flavescens. Flavonoids are a primary bioactive component of Sophora flavescens , which is widely used in traditional Chinese medicine. Understanding flavonoid biosynthesis is of great importance for improving the production of active compounds. In this study, both the total flavonoid content and the contents of six main flavonoid (namely, genistin, trifolirhizin, maackiain, kushenol I, kurarinone, and nor-kurarinone) were significantly higher in triennial S. flavescens than in biennial plants, and the flavonoid content of lateral roots was higher than that of taproots. We attempted to generate exhaustive molecular information on the flavonoid secondary metabolite pathway and to increase the genomic resources for S. flavescens. De novo transcriptome data provided 643,251 unigenes, and 365,572 (56.83 %) were successfully annotated in five public protein databases. The gene expression profiles of taproots and lateral roots clustered with each other and were separated by the cultivation period; the other expression profiles were clustered according to tissue pattern. The differentially expressed unigenes (DEGs) in the lateral roots, taproots and stems between biennial and triennial S. flavescens were identified and subjected to functional annotation enrichment. A total of 92 unigenes encoding well-known enzymes involved in flavonoid biosynthesis were found to show differential expression between biennial and triennial S. flavescens. Furthermore, the comparative expression results of eight unigenes were validated by real-time quantitative PCR (qRT-PCR). The most abundant transcription factors (TFs) that were differentially expressed in S. flavescens were those belonging to the bHLH-, NAC-, ERF- and MYB-related families, and these TFs were identified regardless of the tissue or cultivation period. Our study provides important resources of gene sequences and expression and insights into the molecular mechanism of flavonoid biosynthesis during S. flavescens cultivation. [ABSTRACT FROM AUTHOR]