- G. Freymark (2)
- B.J.M. Gorguet (1)
- P.J. Grauw-van Leeuwen de (1)
- E.W. Gutteling (1)
- J.P.W. Haanstra (4)
- A.W. Heusden van (1)
- C.A. Maliepaard (3)
- J. Ocaña (1)
- L.M.M. Pohu-Flament (1)
- H. Rooij de (1)
- E.H. Schipper (1)
- Y.M. Tikunov (4)
- A. Tiwari (1)
- R.G.F. Visser (5)
- A. Vogelaar (1)
- F. Willeboordse-Vos (1)
- S.C. Wit-Maljaars de (1)
Capturing flavors from Capsicum baccatum by introgression in sweet pepper
Eggink, P.M. ; Tikunov, Y.M. ; Maliepaard, C.A. ; Haanstra, J.P.W. ; Rooij, H. de; Vogelaar, A. ; Gutteling, E.W. ; Freymark, G. ; Bovy, A.G. ; Visser, R.G.F. - \ 2014
Theoretical and Applied Genetics 127 (2014)2. - ISSN 0040-5752 - p. 373 - 390.
plastid compartment size - lycopersicon-esculentum - volatile compounds - anthracnose resistance - chemical-composition - gas-chromatography - sensory evaluation - mass-spectrometry - candidate gene - essential oils
The species Capsicum baccatum includes the most common hot peppers of the Andean cuisine, known for their rich variation in flavors and aromas. So far the C. baccatum genetic variation remained merely concealed for Capsicum annuum breeding, due to post-fertilization genetic barriers encountered in interspecific hybridization. However, to exploit the potential flavor wealth of C. baccatum we combined interspecific crossing with embryo rescue, resulting in a multi-parent BC2S1 population. Volatile and non-volatile compounds plus some physical characters were measured in mature fruits, in combination with taste evaluation by a sensory panel. An enormous variation in biochemical composition and sensory attributes was found, with almost all traits showing transgression. A population-specific genetic linkage map was developed for QTL mapping. BC2S1 QTLs were validated in an experiment with near-isogenic lines, resulting in confirmed genetic effects for physical, biochemical and sensory traits. Three findings are described in more detail: (1) A small C. baccatum LG3 introgression caused an extraordinary effect on flavor, resulting in significantly higher scores for the attributes aroma, flowers, spices, celery and chives. In an attempt to identify the responsible biochemical compounds few consistently up- and down-regulated metabolites were detected. (2) Two introgressions (LG10.1 and LG1) had major effects on terpenoid content of mature fruits, affecting at least 15 different monoterpenes. (3) A second LG3 fragment resulted in a strong increase in Brix without negative effects on fruit size. The mapping strategy, the potential application of studied traits and perspectives for breeding are discussed.
A taste of pepper: genetics, biochemistry and prediction of sweet pepper flavor
Eggink, P.M. - \ 2013
Wageningen University. Promotor(en): Richard Visser, co-promotor(en): Arnaud Bovy; Chris Maliepaard; J.P.W. Haanstra. - S.l. : s.n. - ISBN 9789461737243 - 159
capsicum annuum - paprika's - wilde verwanten - genotypen - chemische samenstelling - smaak - geur en smaak - capsicum baccatum - introgressie - plantenveredeling - capsicum annuum - sweet peppers - wild relatives - genotypes - chemical composition - taste - flavour - capsicum baccatum - introgression - plant breeding
This PhD project started with the composition of a diverse panel of genotypes that represented, (i) roughly the flavor variation in the commercial Capsicum annuum breeding program of Rijk Zwaan, (ii) parents of available mapping populations and (iii) some genotypes that were expected to have extraordinary flavors. The complete set consisted of 35 genotypes of which 24 genotypes were non-pungent. Volatile and non-volatile compounds as well as some breeding parameters were measured in mature fruits of all genotypes throughout the growing season. In addition, from three harvests the non-pungent genotypes were evaluated for taste by a trained descriptive sensory panel.
The biochemical profiling with use of SPME-GC-MS allowed visualization of between- and within-species volatile compound variation. Principal components analysis (PCA) on the intensity patterns of 391 putative volatile compounds revealed individual grouping of C. chinense, C. baccatum var. pendulum and C. annuum, indicating potentially interesting volatile variation present in the former two groups. A large group of saturated and unsaturated esters were mainly responsible for the individual grouping of the C. chinense accessions. Due to the elevated acid concentrations and aberrant volatile profiles of the C. baccatum var. pendulum accessions PEN45 and PEN79, the two BIL populations derived from these accessions were identified as interesting candidates for further study. Compared to e.g. Mazurka the citrate concentration of the C. baccatum accessions was 2.5-3 times higher and the malate concentrations were even up to 12 times higher (Chapter 2).
Based on the non-pungent genotypes, we found highly correlated clusters of volatiles and non-volatiles, which could be related to metabolic pathways and common biochemical precursors (Chapter 3). Contrasts between genotypes were caused by both qualitative and quantitative differences in these metabolic clusters, with the phenolic derivatives, higher alkanes, sesquiterpenes and lipid derived volatiles forming the major determinants. For the description of the non-pungent genotypes the panelists used fourteen attributes to describe the flavor sensation in the mouth/throat, which were the texture attributes crunchiness, stickiness of the skin, toughness and juiciness, the basic taste attributes sweetness and sourness and the retronasal flavor attributes aroma intensity, grassiness, green bean, carrot, fruity/apple, perfume, petrochemical and musty. The variation in flavor could be reduced into two major sensory contrasts, which were a texture related contrast and the basic sweet-sour contrast. The structure of the PCA plots resulting from the analysis with one harvest (Chapter 3) and the analysis with the combined three harvests (Chapter 4) remained almost identical, indicating the stability of these contrasts. To relate the sensory attributes to the metabolite data and to determine the importance of the individual compounds we used Random Forest regression on the individual harvests and on the three harvests together. Several predictors for the attributes aroma, fruity/apple, sourness and sweetness were found in common between harvests, which we proposed as key-metabolites involved in flavor determination of sweet pepper (Chapter 4). This list contains compounds with known relations to attributes, like sweetness and sugars, but also several compounds with new relations. In this respect we have demonstrated for the first time, that the metabolites p-menth-1-en-9-al, (E)-β-ocimene, (Z)-2-penten-1-ol, and 1-methyl-1,4-cyclohexadiene are related to fruity/apple taste and/or sweetness of pepper. For sourness the only compound with a consistent significant contribution was an unknown C6H8O2 compound. We postulated therefore the hypothesis that in pepper the effect of sourness related metabolites is masked by other volatile and non-volatile compounds or texture differences (Chapter 3). Subsequently in Chapter 4 we described a clear sweetness-sourness interaction and demonstrated that the masking effect of fructose and other sugars explained why we did not find organic acids contributing to the prediction of sourness. The major sensory attributes were also predicted between harvests. The Random Forest predictions of the texture related attributes (juiciness, toughness, crunchiness and stickiness of the skin) and sweetness were very good. The predictions of the attributes aroma intensity, sourness and fruity/apple were somewhat lower and more variable between harvests, especially in the second harvest. In general, we concluded that prediction of attributes with higher heritabilities works better and is more consistent over harvests (Chapter 4).
Based on the results of the initial experiments (Chapter 2) the species C. baccatum was chosen for further study. To exploit the potential flavor wealth of C. baccatum PEN45 we combined interspecific crossing with embryo rescue, resulting in a multi-parent BC2S1 population, that was characterized for sensory and biochemical variation (Chapter 5). We developed a population specific genetic linkage map for QTL mapping of characterized traits. Because of the complex structure of our BC2S1 mapping population we encountered several limitations, such as accidental co-segregation, underrepresentation of color linked markers and pre-selection leading to skewness, which might have resulted in false positive or missed QTLs. Despite these limitations, we were still fairly well able to map several biochemical, physical and sensory traits, as demonstrated at first for the (monogenic) control traits red color and pungency in the BC2S1 mapping population and in second instance by validation of genetic effects via an experiment with near-isogenic lines (NILs).This two-step approach turned out to be very powerful, since it led to the identification of the main results from this thesis: (i) Asmall C. baccatum LG3 introgression causing an extraordinary effect on flavor, which resulted in significantly higher scores for the attributes aroma, flowers, spices, celery and chives. In an attempt to identify the responsible biochemical compounds few consistently up- and down-regulated metabolites were detected, including the well-known pepper compound 2-isobutyl-3-methoxypyrazine (down) and 6-methyl-4-oxo-5-heptenal (up); (ii) Two introgressions (LG10.1 and LG1) had major effects on terpenoid content of mature fruits, affecting at least fifteen different monoterpenes; (iii) A second LG3 fragment resulted in a strong increase in Brix (total soluble solids) without negative effects on fruit size (Chapter 5).
In Chapter 6 some extra sensory results of the pungent genotypes are given and a comparison between the two C. baccatum pendulum BILs (PEN45 and PEN79 derived) is made in light of the overall results. Finally the perspectives for breeding are discussed and presented in the form of a flowchart for flavor improvement.
A taste of sweet pepper: Volatile and non-volatile chemical composition of fresh sweet pepper (Capsicum annuum) in relation to sensory evaluation of taste
Eggink, P.M. ; Maliepaard, C.A. ; Tikunov, Y.M. ; Haanstra, J.P.W. ; Bovy, A.G. ; Visser, R.G.F. - \ 2012
Food Chemistry 132 (2012)1. - ISSN 0308-8146 - p. 301 - 310.
bell peppers - gas-chromatography - tomato - fruit - flavor - metabolomics - frutescens - diversity - quality - aroma
In this study volatile and non-volatile compounds, as well as some breeding parameters, were measured in mature fruits of elite sweet pepper (Capsicum annuum) lines and hybrids from a commercial breeding program, several cultivated genotypes and one gene bank accession. In addition, all genotypes were evaluated for taste by a trained descriptive sensory expert panel. Metabolic contrasts between genotypes were caused by clusters of volatile and non-volatile compounds, which could be related to metabolic pathways and common biochemical precursors. Clusters of phenolic derivatives, higher alkanes, sesquiterpenes and lipid derived volatiles formed the major determinants of the genotypic differences. Flavour was described with the use of 14 taste attributes, of which the texture related attributes and the sweet-sour contrast were the most discriminatory factors. The attributes juiciness, toughness, crunchiness, stickiness, sweetness, aroma, sourness and fruity/apple taste could be significantly predicted with combined volatile and non-volatile data. Fructose and (E)-2-hexen-1-ol were highly correlated with aroma, fruity/apple taste and sweetness. New relations were found for fruity/apple taste and sweetness with the compounds p-menth-1-en-9-al, (E)-beta-ocimene, (Z)-2-penten-1-ol and (E)-geranylacetone. Based on the overall biochemical and sensory results, the perspectives for flavour improvement by breeding are discussed.
Prediction of sweet pepper (Capsicum annuum) flavour over different harvests
Eggink, P.M. ; Maliepaard, C.A. ; Tikunov, Y.M. ; Haanstra, J.P.W. ; Pohu-Flament, L.M.M. ; Wit-Maljaars, S.C. de; Willeboordse-Vos, F. ; Bos, S. ; Benning-de Waard, C. ; Grauw-van Leeuwen, P.J. de; Freymark, G. ; Bovy, A.G. ; Visser, R.G.F. - \ 2012
Euphytica 187 (2012)1. - ISSN 0014-2336 - p. 117 - 131.
lycopersicon-esculentum - chemical-composition - volatile compounds - metabolomics - tomatoes
To better understand and predict the complex multifactorial trait flavor, volatile and non-volatile components were measured in fresh sweet pepper (Capsicum annuum) fruits throughout the growing season in a diverse panel of 24 breeding lines, hybrids, several cultivated genotypes and one gene bank accession. Biochemical profiles were linked to individual flavor attributes, that were objectively quantified by a trained descriptive expert panel. We used a Random Forest regression approach for prediction of the flavor attributes within and between harvests. Predictions of texture related attributes (juiciness, toughness, crunchiness and stickiness of the skin) and sweetness were good (around 60–65 %in the analyses with the three harvests combined). The predictions of the attributes aroma intensity, sourness and fruity/apple were somewhat lower and more variable between harvests. (E)-2-hexen-1-ol, neopentane, p-menth-1-en-9-al, 3-hepten-2-one, (Z)-b-ocimene, (Z)-2-penten-1-ol, 1-methyl-1,4-cyclohexadiene, glucose, fructose and three unknown volatile compounds were identified as key-metabolites involved in the flavor differences between both genotypes and harvests. The complex nature of flavor is exemplified by the observed masking effect of fructose and other sugars on sourness and sourness related metabolites, like citrate. The knowledge obtained from the overall biochemical, sensory and prediction analyses forms a basis for targeted flavor improvement by breeding.
|Characterization of volatile and non-volatile compounds of fresh pepper (Capsicum annuum)
Eggink, P.M. ; Haanstra, J.P.W. ; Tikunov, Y.M. ; Bovy, A.G. ; Visser, R.G.F. - \ 2010
In: Proceedings of the XIVth EUCARPIA Meeting on Genetics and Breeding of Capsicum & Eggplant, Valencia, Spain. - Universidad Politécnica de Valencia - ISBN 9788469341391 - p. 251 - 259.
In this study volatile and non-volatile compounds and several agronomical important parameters were measured in mature fruits of elite sweet pepper breeding lines and hybrids and several genebank accessions from different Capsicum species. The sweet pepper breeding lines and hybrids were chosen to roughly represent the expected variation in flavor of Capsicum annuum in the Rijk Zwaan germplasm. The genebank accessions were either chosen because they were expected to have unique combinations of aromas and flavors, according to experience and/or literature, or were parents of mapping populations. The biochemical profiling allowed visualization of between- and within-species metabolic variation and stability during the year. In general, total soluble solids content (Brix) was genotype-dependent and fluctuated only slightly throughout the growing season, with uncultivated genotypes showing the largest changes. The species C. chinense, C. baccatum var. pendulum and C. annuum could be clearly separated by principle component analysis based on profiles of 391 volatile compounds. Especially for breeding purposes it seems to be interesting to study this variation in more detail, trying to unravel the complex genetics of the different pepper flavor aspects.
Mapping and characterization of novel parthenocarpy QTLs in tomato
Gorguet, B.J.M. ; Eggink, P.M. ; Ocaña, J. ; Tiwari, A. ; Schipper, E.H. ; Finkers, H.J. ; Visser, R.G.F. ; Heusden, A.W. van - \ 2008
Theoretical and Applied Genetics 116 (2008)6. - ISSN 0040-5752 - p. 755 - 767.
quantitative trait loci - lycopersicon-esculentum - botrytis-cinerea - resistance - hirsutum - set - auxin-response-factor8 - identification - introgression - chromosomes
Parthenocarpy is the development of the fruit in absence of pollination and/or fertilization. In tomato, parthenocarpy is considered as an attractive trait to solve the problems of fruit setting under unfavorable conditions. We studied the genetics of parthenocarpy in two different lines, IL5-1 and IVT-line 1, both carrying Solanum habrochaites chromosome segments. Parthenocarpy in IL5-1 is under the control of two QTLs, one on chromosome 4 (pat4.1) and one on chromosome 5 (pat5.1). IVT-line 1 also contains two parthenocarpy QTLs, one on chromosome 4 (pat4.2) and one on chromosome 9 (pat9.1). In addition, we identified one stigma exsertion locus in IL5-1, located on the long arm of chromosome 5 (se5.1). It is likely that pat4.1, from IL5-1 and pat4.2, from IVT-line 1, both located near the centromere of chromosome 4 are allelic. By making use of the microsynteny between tomato and Arabidopsis in this genetic region, we identified ARF8 as a potential candidate gene for these two QTLs. ARF8 is known to act as an inhibitor for further carpel development in Arabidopsis, in absence of pollination/fertilization. Expression of an aberrant form of the Arabidopsis ARF8 gene, in tomato, has been found to cause parthenocarpy. This candidate gene approach may lead to the first isolation of a parthenocarpy gene in tomato and will allow further use in several crop species