Sierd Zijlstra - Academia.edu (original) (raw)
Papers by Sierd Zijlstra
Journal of Chemical Ecology, 2003
Cucurbitacins are bitter triterpenoid compounds that are toxic to most organisms and occur widely... more Cucurbitacins are bitter triterpenoid compounds that are toxic to most organisms and occur widely in wild and cultivated Cucurbitaceae. The only cucurbitacin identified in Cucumis sativus is cucurbitacin C. The bitter taste of cucumber has been correlated with resistance to the spider mite Tetranychus urticae, but a quantitative relationship has not been established. We determined the spider mite resistance and
HortScience, 1991
Crossing barriers between white- and purple-flowered species were examined. Four accessions of Ca... more Crossing barriers between white- and purple-flowered species were examined. Four accessions of Capsicum annuum and three of C. pubescens were reciprocally crossed with one to four accessions of C. baccatum, C. cardenasii, C. chacoense, C. chinense, C. eximium, C. frutescens, C. galapagoense, and C. praetermissum. Capsicum chacoense is the only white-flowered species that inhibits C. annuum pollen tube growth but allows C. pubescens pollen tube penetration into the egg cell. Capsicum cardenasii and C. eximium exhibit similar crossabilities with C. annuum and C. pubescens: pollen tubes of C. cardenasii and of C. eximium can penetrate the egg cells of C. annuum but not vice versa, and pollen tubes of C. pubescens can penetrate the egg cells of C. cardenasii and of C. eximium but not vice versa.
Journal of the American Society for Horticultural Science, 1992
Powdery mildew-resistant (PMR) cultivars of cucumber (Cucumis sativus L.) grown in greenhouses in... more Powdery mildew-resistant (PMR) cultivars of cucumber (Cucumis sativus L.) grown in greenhouses in the Netherlands during winter show chlorosis on the full-grown leaves of the main stem. The symptoms are yellowing and occasional necrosis between the main veins of the leaves, resembling symptoms of P toxicity. Severity of the chlorosis may vary from one winter to another. Variation is also observed in the severity of the symptoms between cultivars and individual plants of a cultivar. High P nutrition results in an increase of the severity of chlorosis and provides a better discriminating environment for the selection of PMR genotypes that are less susceptible for leaf chlorosis.
Acta Botanica Neerlandica, 1990
Plants were regenerated via embryogenesis from leaf explant-derived callus of cucumber (Cucumis s... more Plants were regenerated via embryogenesis from leaf explant-derived callus of cucumber (Cucumis sativus L. cv. Hokus). Somaclonal variation was evaluated in the regenerated plants (R) generation) and in the selfed progeny (R z). Considerable variation was found in the young R) plants, but it was of a transient nature. Mature R) plants showed slight abnormalities which were not directly transmitted to the progeny. Seed production of the R1s was variable and very poor, as was seed germination. This is probably caused by dysfunctioning of generative tissue and cells and might have a genetic base. Of eight R z lines analysed, one was tetraploid and five expressed a low extent of variability, probably of a genetic nature. Most of the R, plants were phenotypically normal. In a yield analysis, genetic variation useful for improvement of crop performance has not been detected. It is suggested that in cucumber the generative phase acts as a sieve for genetically based somaclonal variation.
Euphytica, 1997
Three greenhouse cucumber (Cucumis sativus L.) accessions, previously selected for low levels of ... more Three greenhouse cucumber (Cucumis sativus L.) accessions, previously selected for low levels of damage after infestation with Frankliniella occidentalis (Pergande), were tested for resistance against F. occidentalis in a no-choice greenhouse experiment at the mature plant stage. The three accessions showed a strong reduction in thrips damage compared to the susceptible control. The effects of leaf position and plant age
ABSTRACT An important problem in organic carrot production in the Netherlands is the occurrence o... more ABSTRACT An important problem in organic carrot production in the Netherlands is the occurrence of black spots during storage. Several different fungal pathogens cause similar symptoms, which are collectively known as black spot diseases. We identified Alternaria radicina, A. dauci and Rhexocercosporidium carotae (syn. Acrothecium carotae) as the most prevalent black spot pathogens. We developed laboratory test methods for resistance to A. radicina and R. carotae, and assessed resistance in a collection of cultivated varieties and more exotic material
The current powdery mildew (Sphaerotheca fuligninea) resistant cucumber varieties suffer from lea... more The current powdery mildew (Sphaerotheca fuligninea) resistant cucumber varieties suffer from leaf chlorosis during autumn, winter and early spring cultivation in the Netherlands. Therefore screening was carried out for novel powdery mildew resistance genes. From 177 accessions, derived from different sources, 108 accessions proved to be partially resistant to S. fuliginea. Crosses were made with 53 resistant accessions to distinguish the presence of novel genes. It is likely that the accessions C. sativus 2145, C. sativus LV 41, PI 188807, Vladivostokij, White and Yellow 1 have one or more recessive powdery mildew resistance genes, different from powdery mildew resistance genes of the line NPI, which was used for variety breeding. Powdery mildew resistance tests with S. fuliginea give similar results in different regions of the world .
Nederland kent van oorsprong een rijke variatie aan bonen. Dankzij de Oerakker en de Wageningse g... more Nederland kent van oorsprong een rijke variatie aan bonen. Dankzij de Oerakker en de Wageningse genenbank zijn oude streekrassen bewaard. Mogelijk zitten daar rassen met nieuwe kansen bij
Journal of Chemical Ecology, 2003
Cucurbitacins are bitter triterpenoid compounds that are toxic to most organisms and occur widely... more Cucurbitacins are bitter triterpenoid compounds that are toxic to most organisms and occur widely in wild and cultivated Cucurbitaceae. The only cucurbitacin identified in Cucumis sativus is cucurbitacin C. The bitter taste of cucumber has been correlated with resistance to the spider mite Tetranychus urticae, but a quantitative relationship has not been established. We determined the spider mite resistance and
HortScience, 1991
Crossing barriers between white- and purple-flowered species were examined. Four accessions of Ca... more Crossing barriers between white- and purple-flowered species were examined. Four accessions of Capsicum annuum and three of C. pubescens were reciprocally crossed with one to four accessions of C. baccatum, C. cardenasii, C. chacoense, C. chinense, C. eximium, C. frutescens, C. galapagoense, and C. praetermissum. Capsicum chacoense is the only white-flowered species that inhibits C. annuum pollen tube growth but allows C. pubescens pollen tube penetration into the egg cell. Capsicum cardenasii and C. eximium exhibit similar crossabilities with C. annuum and C. pubescens: pollen tubes of C. cardenasii and of C. eximium can penetrate the egg cells of C. annuum but not vice versa, and pollen tubes of C. pubescens can penetrate the egg cells of C. cardenasii and of C. eximium but not vice versa.
Journal of the American Society for Horticultural Science, 1992
Powdery mildew-resistant (PMR) cultivars of cucumber (Cucumis sativus L.) grown in greenhouses in... more Powdery mildew-resistant (PMR) cultivars of cucumber (Cucumis sativus L.) grown in greenhouses in the Netherlands during winter show chlorosis on the full-grown leaves of the main stem. The symptoms are yellowing and occasional necrosis between the main veins of the leaves, resembling symptoms of P toxicity. Severity of the chlorosis may vary from one winter to another. Variation is also observed in the severity of the symptoms between cultivars and individual plants of a cultivar. High P nutrition results in an increase of the severity of chlorosis and provides a better discriminating environment for the selection of PMR genotypes that are less susceptible for leaf chlorosis.
Acta Botanica Neerlandica, 1990
Plants were regenerated via embryogenesis from leaf explant-derived callus of cucumber (Cucumis s... more Plants were regenerated via embryogenesis from leaf explant-derived callus of cucumber (Cucumis sativus L. cv. Hokus). Somaclonal variation was evaluated in the regenerated plants (R) generation) and in the selfed progeny (R z). Considerable variation was found in the young R) plants, but it was of a transient nature. Mature R) plants showed slight abnormalities which were not directly transmitted to the progeny. Seed production of the R1s was variable and very poor, as was seed germination. This is probably caused by dysfunctioning of generative tissue and cells and might have a genetic base. Of eight R z lines analysed, one was tetraploid and five expressed a low extent of variability, probably of a genetic nature. Most of the R, plants were phenotypically normal. In a yield analysis, genetic variation useful for improvement of crop performance has not been detected. It is suggested that in cucumber the generative phase acts as a sieve for genetically based somaclonal variation.
Euphytica, 1997
Three greenhouse cucumber (Cucumis sativus L.) accessions, previously selected for low levels of ... more Three greenhouse cucumber (Cucumis sativus L.) accessions, previously selected for low levels of damage after infestation with Frankliniella occidentalis (Pergande), were tested for resistance against F. occidentalis in a no-choice greenhouse experiment at the mature plant stage. The three accessions showed a strong reduction in thrips damage compared to the susceptible control. The effects of leaf position and plant age
ABSTRACT An important problem in organic carrot production in the Netherlands is the occurrence o... more ABSTRACT An important problem in organic carrot production in the Netherlands is the occurrence of black spots during storage. Several different fungal pathogens cause similar symptoms, which are collectively known as black spot diseases. We identified Alternaria radicina, A. dauci and Rhexocercosporidium carotae (syn. Acrothecium carotae) as the most prevalent black spot pathogens. We developed laboratory test methods for resistance to A. radicina and R. carotae, and assessed resistance in a collection of cultivated varieties and more exotic material
The current powdery mildew (Sphaerotheca fuligninea) resistant cucumber varieties suffer from lea... more The current powdery mildew (Sphaerotheca fuligninea) resistant cucumber varieties suffer from leaf chlorosis during autumn, winter and early spring cultivation in the Netherlands. Therefore screening was carried out for novel powdery mildew resistance genes. From 177 accessions, derived from different sources, 108 accessions proved to be partially resistant to S. fuliginea. Crosses were made with 53 resistant accessions to distinguish the presence of novel genes. It is likely that the accessions C. sativus 2145, C. sativus LV 41, PI 188807, Vladivostokij, White and Yellow 1 have one or more recessive powdery mildew resistance genes, different from powdery mildew resistance genes of the line NPI, which was used for variety breeding. Powdery mildew resistance tests with S. fuliginea give similar results in different regions of the world .
Nederland kent van oorsprong een rijke variatie aan bonen. Dankzij de Oerakker en de Wageningse g... more Nederland kent van oorsprong een rijke variatie aan bonen. Dankzij de Oerakker en de Wageningse genenbank zijn oude streekrassen bewaard. Mogelijk zitten daar rassen met nieuwe kansen bij