However, such approaches can only be successful in the presence of comprehensive, high-quality phenotypic information (Still 2007). Genetic Resources and Crop Evolution, 64, 55–71.
This resulted in 310,262 individual mass signals. Photo by Shutterstock. © 2020 Springer Nature Switzerland AG.
However, comprehensive metabolomics studies of the lettuce gene pool are yet non-existing.
Vitamin C levels showed considerable variation both within and between the examined Lactuca species (Fig. The finding that the observed genotype clustering patterns were largely in line with taxonomic relationships indicate that the variation in phytochemical composition is to a large extent genetically determined, suggesting excellent possibilities for breeding towards new lettuce varieties with improved trait characteristics. Material for quality control samples (technical repeats) was prepared by pooling an equal aliquot of the frozen powder of each sample. Genetic Resources and Crop Evolution, 65, 1963–1978.
American Journal of Botany, 85, 1517–1530. We aimed to identify promising genetic resources for the improvement of phytochemical composition of lettuce varieties.
RdV and RvT designed the research. Saved from myrecipes.com. Secondary metabolism and antioxidants are involved in environmental adaptation and stress tolerance in lettuce.
Many phytochemicals appeared species-specific, of which several are generally related to traits that are associated with plant health or nutritional value. Hierarchical cluster analysis of the research lines, denoted by taxonomic group and line identifier, based on 2026 metabolites detected by LCMS.
FAOSTAT (2017). Rewiring of the fruit metabolome in tomato breeding. Plant Genetic Resources: Characterization and Utilization, 12, 298–307.
As shown in Fig.
2016; Walley et al. Mean value of the primary gene pool species L. georgica resembled that of L. virosa. Metabolomics Particularly in the United States and Europe, new lettuce varieties are regularly introduced to the market. International Journal of Molecular Sciences, 14, 12780–12805. The number of phytochemicals observed in only a single species ranged from 22 in L. serriola to 51 in L. sativa. These genotypes were selected from the lettuce collection of the Centre for Genetic Resources, the Netherlands (CGN), which currently is the largest in the world and which has a relatively high representation of wild relatives. The compounds present in these aqueous-methanol extracts were separated on a Luna C18 column (2.0 × 150 mm, 3 µm; Phenomenex) at 40 °C, using an Acquity HPLC module (Waters) to apply a 45 min linear gradient of 5–75% acetonitrile in 0.1% FA in water at a flow rate of 0.19 ml/min.
Fernie, A. R., & Schauer, N. (2009).
Crop-related species are often classified according to the gene pool concept, which is based on the level of inter-fertility with the crop species. The total analysis time was 162 h without interruption. Abu-Reidah, I. M., Contreras, M. M., Arráez-Román, D., Segura-Carretero, A., & Fernández-Gutiérrez, A.
For extraction of ascorbic acid (vitamin C), 300 mg frozen leaf powder was mixed with 1.2 ml of ice cold extraction solvent consisting of 5% meta-phosphoric acid in water containing 1 mM diethylene penta-acetic acid.
In J. Prohens & F. Nuez (Eds.
Metabolite data were related to trait data, such as resistances to pests and diseases, previously collected for accessions of the CGN lettuce collection (CGN 2017c) using random forests (Breiman 2001), as implemented in the R package RandomForest (Liaw and Wiener 2002).
The final prediction is then a combination of the predictions of the individual trees. 2016). The supernatant was filtered over an 13 mm nylon-66 MDI filter, with a pore size of 0.2 µm and transferred to an 1.8 ml HPLC vial.
Cooking Method. Ryder, E. J. The technique is appealing because it usually requires no tuning, and automatically returns cross-validated prediction errors. Recently, a similar conclusion was drawn from a molecular marker study in L. georgica and related species (Beharav et al. Phytochemical variation was investigated using 150 Lactuca genebank accessions, comprising a core set of the lettuce gene pool, and resulting data were related to available phenotypic information.
Variable importance is assessed by observing the change in prediction error upon removing a variable, leading to an increase in prediction error in case of important variables. . Multiples of these mean values were observed for the more primitive crop types cos, stalk and oilseed lettuce. Google Scholar. 2012). Below is the link to the electronic supplementary material.
2017) and hence indicate that the observed variation in phytochemicals is to a large extent genetically determined, providing excellent possibilities for breeding towards novel lettuce varieties with improved phytochemical composition.
Nature Communications, 8, 14953. https://doi.org/10.1038/ncomms14953. The two species also clustered together based on their leaf phytochemical composition.
Article Google Scholar.
As popular as lettuce is for salads and sandwiches, you may not know that there are many different varieties. Google Scholar. Google Scholar. All plants of the core set, with the exception of the outcrossing species, were maintained for seed production by self-fertilization. A separate exploration of the LCMS data was performed for L. sativa and its three wild relatives most commonly used in plant breeding, i.e.
Since lettuce is regarded as a good source of vitamin C in the human diet, we separately extracted and quantified vitamin C (ascorbic acid) using a dedicated HPLC method.
Such key traits are known to be largely dependent on the ability of varieties to produce specific phytochemicals.
All samples were maintained at − 80 °C awaiting further processing for metabolite analysis. The contribution of RvT was part of the Fundamental Research Programme on Sustainable Food and non-Food Production (KB-21-004-001) funded by the Dutch Ministry of Agriculture, Nature and Food Quality. In order to prevent possible batch effects in the LCMS-analysis, all samples were randomly analysed in a single series.
Random forests. Samples were vortexed, sonicated for 15 min and centrifuged at maximum speed for 20 min. CGN (2017c).
Lettuce. PubMed Google Scholar.
Oilseed lettuces are mainly grown in Egypt for cooking purposes due to the high oil content of the seeds. Alternate name: Oak leaf. Stir Fries. Journal of Mass Spectrometry, 52, 873–902. Due to experimental failure, vitamin C data were absent for both TKI-454 and TKI-471. Each plot also shows the LCMS data of the other three species.
Six quality control samples (QCs) were included per batch and equally divided over the study samples. Neveu, V., Perez-Jiménez, J., Vos, F., Crespy, V., du Chaffaut, L., Mennen, L., et al. Genome assembly with in vitro proximity ligation data and whole-genome triplication in lettuce. Saved by MyRecipes. volume 14, Article number: 146 (2018)
Liquid chromatography coupled to high resolution mass spectrometry, herein referred to as LCMS, is the most preferred platform for detecting a large variety of non-volatile semi-polar secondary metabolites, including major biochemical classes like phenolic acids, phenylpropanoids, flavonoids, alkaloids, saponins, glucosinolates and sesquiterpenes, next to many other, yet unknown compounds (De Vos et al. The observed phytochemical relationships are largely in line with those based on molecular marker and DNA sequence data (Koopman et al. Kim, M. J., Moon, Y., Tou, J. C., Mou, B., & Waterland, N. L. (2016). Analytical Chemistry, 81, 3079–3086. Ascorbic acid eluted at a retention time of 5.2 min and its peak area was determined at 262 nm. CGN (2017b).
The lettuce genome has recently been published (Reyes-Chin-Wo et al. Samples were prepared in two batches of 75 randomly chosen genotypes each. 75–116). Out of the 1932 phytochemicals detected in either of the wild species L. serriola, L. saligna or L. virosa, 264 (13.7%) were not observed in L. sativa.
Samples of successful seed multiplications were stored at CGN as a special collection (Van Treuren and Van Hintum 2014) of Single Seed Descent lines (CGN 2017b).
L. serriola, L. saligna and L. virosa, in order to determine phytochemical overlap and to identify compounds most characteristic to one of these species. Mou, B. According to the Phenol-Explorer database (Neveu et al. 3, vegetable crops (pp.
2012). Nutritional value, bioactive compounds and health benefits of lettuce (Lactuca sativa L.). Research lines for the present study were chosen from a group of nearly 500 ex situ accessions selected for DNA re-sequencing within the context of the project entitled ‘International Lactuca Genomics Consortium’ (ILGC).
Lebeda, A., Ryder, E. J., Grube, R., Doležalová, I., & Krístková, E. (2007).
Apr 13, 2020 Westend61 Getty Images. Perception of bitterness, sweetness and liking of different genotypes of lettuce. Metalign: Interface-driven, versatile metabolomics tool for hyphenated full-scan mass spectrometry data preprocessing. 2009; Chadwick et al. In R. J. Singh (Ed.
Journal of Chromatography A, 1313, 212–227. 2016), was present in all accessions of L. saligna, in 2 out of the 21 L. serriola accessions and in both L. perennis accessions (Supplementary Table 2).
Several SLs including lactucin, 8-deoxylactucin and lactucopicrin are well-known for their bitter taste (e.g.
2017). https://doi.org/10.1007/s11306-018-1443-8, DOI: https://doi.org/10.1007/s11306-018-1443-8, Over 10 million scientific documents at your fingertips, Not logged in Inspection of the models leads to estimates of the importance of each phytochemical in the models, the top 20 of which is visualized in Fig.
Based on the detected accurate mass of the putative molecular ions, and for selected metabolites also their MSn fragmentation data, we could tentatively annotate a series of amino acids, organic acids, phenylpropanoids, flavonoids, anthocyanins and sesquiterpene lactones among the 2026 metabolites.
All samples of L. saligna, representing the secondary gene pool, clustered together in a single group. Oakleaf lettuce.
Lettuce (Lactuca sativa L.) is generally not specifically acknowledged for its taste and nutritional value, while its cultivation suffers from limited resistance against several pests and diseases. Reyes-Chin-Wo, S., Wang, Z., Yang, X., Kozik, A., Arikit, S., Song, C., et al. The strong variation in phytochemical composition among these four species was also evident from phytochemicals that were more or less species-specific (Fig.
A perfect correlation is indicated by the grey line. 2007) by adding 900 µl of 99.87% methanol (MeOH) containing 0.13% formic acid (FA), which resulted in a final concentration of about 75% MeOH and 0.1% FA assuming a leaf water content of about 95%. For this analysis TKI-139 and TKI-140 were disregarded, as these oilseed samples were found to represent outliers within the L. sativa group (results not shown). CAS For lettuce, large-scale or essentially untargeted LCMS-based metabolomics approaches have previously been used to investigate metabolite differences among babyleaf, romaine and iceberg cultivar types (Abu-Reidah et al.
The CGN lettuce collection.