Metabolic changes during wheat microspore embryogenesis induction using the highly responsive cultivar Svilena

Androgenetically-derived haploids can be obtained by inducing embryogenesis in microspores. Thus, full homozygosity is achieved in a single generation, oppositely to conventional plant breeding programs Here, the metabolite profile of embryogenic microspores of Triticum aestivum was acquired and integrated with transcriptomic existing data from the same samples in an effort to identify the key metabolic processes occurring during the early stages of microspore embryogenesis. Primary metabolites and transcription profiles were identified at three time points: prior to and immediately following a low temperature pre-treatment given to uninuclear microspores, and after the first nuclear division. This is the first time an integrative -omics analysis is reported in microspore embryogenesis in T. aestivum. The key findings were that the energy produced during the pre-treatment was obtained from the tricarboxylic acid (TCA) cycle and from starch degradation, while starch storage resumed after the first nuclear division. Intermediates of the TCA cycle were highly demanded from a very active amino acid metabolism. The transcription profiles of genes encoding enzymes involved in amino acid synthesis differed from the metabolite profiles. The abundance of glutamine synthetase was correlated with that of glutamine. Cytosolic glutamine synthetase isoform 1 was found predominantly after the nuclear division. Overall, energy production was shown to represent a major component of the de-differentiation process induced by the pre-treatment, supporting a highly active amino acid metabolism

Additional file 5: Table S5. of Analysis of wheat microspore embryogenesis induction by transcriptome and small RNA sequencing using the highly responsive cultivar “Svilena”

Stage specific transcripts. Listing of restructured de novo assembled transcripts with stage-specific expression (at least 0.5 qnrpm in all replicates) including BLASTx top hits. (XLS 88 kb

Studies of genetic diversity and genome‐wide association for vitamin C content in lettuce (Lactuca sativa L.) using high‐throughput SNP arrays

Abstract Lettuce (Lactuca sativa L.) is a source of beneficial compounds though they are generally present in low quantities. We used 40K Axiom and 9K Infinium SNP (single nucleotide polymorphism) arrays to (i) explore the genetic variability in 21 varieties and (ii) carry out genome‐wide association studies (GWAS) of vitamin C content in21 varieties and a population of 205 plants from the richest variety in vitamin C (‘Lechuga del Pirineo’). Structure and phylogenetic analyses showed that the group formed mainly by traditional varieties was the most diverse, whereas the red commercial varieties clustered together and very distinguishably apart from the rest. GWAS consistently detected, in a region of chromosome 2, several SNPs related to dehydroascorbic acid (a form of vitamin C) content using three different methods to assess population structure, subpopulation membership coefficients, multidimensional scaling, and principal component analysis. The latter detected the highest number of SNPs (17) and the most significantly associated, 12 of them showing a high linkage disequilibrium with the lead SNP. Among the 84 genes in the region, some have been reported to be related to vitamin C content or antioxidant status in other crops either directly, like those encoding long non‐coding RNA, several F‐box proteins, and a pectinesterase/pectinesterase inhibitor, or indirectly, like extensin‐1‐like protein and endoglucanase 2 genes. The involvement of other genes identified within the region in vitamin C levels needs to be further studied. Understanding the genetic control of such an important quality trait in lettuce becomes very relevant from a breeding perspective

Additional file 13: Table S12. of Analysis of wheat microspore embryogenesis induction by transcriptome and small RNA sequencing using the highly responsive cultivar “Svilena”

miRNA prediction results. Results from miRNA precursor predictions using miRDeep-P [59] performed from sRNA sequencing data individually for all stage replicates. (XLS 790 kb