Climate changes leading to increasingly longer seasonal drought periods in large parts of the wor... more Climate changes leading to increasingly longer seasonal drought periods in large parts of the world increase the necessity for breeding drought-tolerant crops. Cultivated potato (Solanum tuberosum), the third most important vegetable crop worldwide, is regarded as drought-sensitive due to its shallow root architecture. Two German tetraploid potato cultivars differing in drought tolerance and their F1-progeny were evaluated under various drought scenarios. Bulked segregant analyses were combined with whole-genome sequencing (BSA-Seq) using contrasting bulks of drought-tolerant and drought-sensitive F1-clones. Applying QTLseqr, 15 QTLs comprising 588,983 single nucleotide polymorphisms (SNPs) in 2325 genes associated with drought stress tolerance were identified. SeqSNP analyses in an association panel of 34 mostly starch potato varieties using 1-8 SNPs for each of 188 selected genes narrowed the number of candidate genes down to 10. In addition, ent-kaurene synthase B was the only gene present under QTL 10. Eight of the identified genes (StABP1,
ABSTRACT Sclerotinia sclerotiorum is considered the most devastating pathogen of sunflower grown ... more ABSTRACT Sclerotinia sclerotiorum is considered the most devastating pathogen of sunflower grown in humid environments. In this study, progenies of partial hybrids between Helianthus maximiliani, a wild species that has been shown to be resistant to S. sclerotiorum, and H. annuus were characterized by amplified fragment length polymorphism (AFLP) analysis to identify whether there are introgressions from H. maximiliani into the cultivated sunflower at the molecular level. Wild species-specific fragments as well as fragments not found in either parent were detected. Progenies tended to cluster together according to the original partial hybrids in the dendrogram by the use of bootstrap procedures. The progenies were studied for their reaction to S. sclerotiorum using artificial inoculation of sunflower heads. Some of the progenies showed a higher level of resistance compared with resistant inbred lines. It was possible to identify two AFLP-fragments which seem to be linked to Sclerotinia resistance.
Current plant science and biotechnology in agriculture, 1997
Cultivated sunflower (Helianthus annuus L.) is one of the most important oil crops of the world. ... more Cultivated sunflower (Helianthus annuus L.) is one of the most important oil crops of the world. Its seed oil can be used for human consumption as well as a raw material for oleochemistry. It can also be used as a substitute for mineral oil in various applications, such as fuels, lubricants or oils for hydraulic systems.
The SF21 proteins were originally identified in sunflower pollen and in the stigmatic and transmi... more The SF21 proteins were originally identified in sunflower pollen and in the stigmatic and transmitting tissues of sunflower pistils [Kräuter
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Molecular characterization of 28 CMS sources and the fertile cytoplasm of H. annuus in sunflower ... more Molecular characterization of 28 CMS sources and the fertile cytoplasm of H. annuus in sunflower demonstrated that cytoplasms different by their origin show a considerable similarity that cannot be expected from their pedigree. Cluster analysis using the UPGMA method allowed differentiating 10 mitochondrial (mt) types based on RFLP data. Characteristic proteins specific for one or more CMS sources could be identified which correspond to the mt types. In addition, the data obtained on fertility restoration for a subset of nine new CMS sources support the classification of the cytoplasms made on mtDNA level as demonstrated in the UPGMA dendrogram. A map-based cloning approach is followed for the isolation of the restorer gene Rf1, which restores pollen fertility in hybrids based on PET1. Markers closely linked to the restorer gene could be identified using AFLP and RAPD technologies. A bacterial artificial chromosome (BAC) library was constructed using the sunflower restorer line RHA325 and pBeloBAC11 as vector. The first sunflower BAC library corresponds to 1.7 haploid genome equivalents (104,736 clones, average insert size approx. 50 kb). Use of STS markers, which had been developed from RAPD markers, allowed to identify three BAC clones by colony hybridization against high density filters. DNA fingerprinting using HindIII allowed to build a contig for the restorer locus Rf1.
International Journal of Molecular Sciences, Jun 7, 2021
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
ABSTRACT The development of commercial sunflower hybrids based on new CMS sources is of special i... more ABSTRACT The development of commercial sunflower hybrids based on new CMS sources is of special interest for reducing the potential risk of vulnerability to pathogens and for increasing genetic diversity. From 263 test crosses involving nine new CMS sources, i.e. ANL1, ANL2, MAX1, PEF1, PET2, ANN1, ANN2, ANNS and ANN4, five lines were selected as potential restorers for PEF1, PET2 and ANN4. In test crosses between all nine CMS sources and these five restorer lines evaluated in 2 years, seven fully restored hybrids could be identified. These hybrids, based on ANL1, ANL2, MAX1, PEF1, PET2, and ANN4, showed good agronomic performance for plant height, days to flowering, maturity and oil content. Segregation analyses of the F2 populations indicate that a single dominant restorer gene was sufficient to restore pollen production of hybrids based on ANL2, PEF1 and PET2. For restoration of ANN4, two dominant complementary genes are required. In restoration of fertility in the crosses of ANL1 and MAX1 investigated, two dominant genes are involved each of which on its own allows the production of fertile plants.
Page 1. Development of sequence-tagged site markers linked to the pillar growth type in peach (Pr... more Page 1. Development of sequence-tagged site markers linked to the pillar growth type in peach (Prunus persica) Osama SAJER 1 , Ralph SCORZA 2 , Chris DARDICK 2 , Tetyana ZHEBENTYAYEVA 3 , Albert G. ABBOTT 3 and ... 2003, Cipriani et al. 1999, Dirlewanger et al. ...
Fertility restoration by dominant nuclear genes is essential for hybrid breeding based on cytopla... more Fertility restoration by dominant nuclear genes is essential for hybrid breeding based on cytoplasmic male sterility (CMS) to obtain heterotic effects and high seed yields. In sunflower, only the PET1 sterility inducing cytoplasm has been used in commercial hybrid breeding until now. This particular male sterility was derived from an interspecific hybrid Helianthus petiolaris × H. annuus. For the recent
Systems responses to drought stress of four potato reference cultivars with differential drought ... more Systems responses to drought stress of four potato reference cultivars with differential drought tolerance (Solanum tuberosum L.) were investigated by metabolome profiling and RNA sequencing. Systems analysis was based on independent field and greenhouse trials. Robust differential drought responses across all cultivars under both conditions comprised changes of proline, raffinose, galactinol, arabitol, arabinonic acid, chlorogenic acid and 102 transcript levels. The encoded genes contained a high proportion of heat shock proteins and proteins with signalling or regulatory functions, for example, a homolog of abscisic acid receptor PYL4. Constitutive differences of the tolerant compared with the sensitive cultivars included arbutin, octopamine, ribitol and 248 transcripts. The gene products of many of these transcripts were pathogen response related, such as receptor kinases, or regulatory proteins, for example, a homolog of the Arabidopsis FOUR LIPS MYB-regulator of stomatal cell proliferation. Functional enrichment analyses imply heat stress as a major acclimation component of potato leaves to long-term drought stress. Enhanced heat stress during drought can be caused by loss of transpiration cooling. This effect and CO 2 limitation are the main consequences of drought-induced or abscisic acidinduced stomatal closure. Constitutive differences in metabolite and transcript levels between tolerant and sensitive cultivars indicate interactions of drought tolerance and pathogen resistance in potato.
The mmt thorouJ!h~l' im•t•sti}!ated C'.\JS ~l11t! in sw!flower i.~ the l'l:'T/ (or Leclercq) c:vt... more The mmt thorouJ!h~l' im•t•sti}!ated C'.\JS ~l11t! in sw!flower i.~ the l'l:'T/ (or Leclercq) c:vtoplasm. The tii'J!tlllization oft he mtfJX•lt?(male sterile (/'/:'TI c:rtoplasm) mulji•rtile litu•s d(fli'n on~v hy tm II kh itll'ersion and 11 5 kh insertion. Due to thi.~ in~ertionam•w IIJI<'III'<'adingfiwue. orfl/521, is ctwtted i11the 3'~/lankinJ! re~:io11 t?(the atpA ~:ene. 71te
In sunflower, commercial hybrid breeding is based on a single CMSinducing cytoplasm, the so-calle... more In sunflower, commercial hybrid breeding is based on a single CMSinducing cytoplasm, the so-called PET1 cytoplasm. The introduction of one dominant, nuclear-encoded restorer gene (Rf1) is in most cases sufficient for fertility restoration. Little has been learned so far about the mode of action of the restorer gene Rf1. For map-based cloning of the restorer gene Rf1, an F 2 population of the cross RHA325 (cms) x HA342 has been used. The χ²-test confirmed segregation for one dominant gene which corresponds to Rf1. For the AFLP analyses 256 EcoRI/MseI primer combinations have been used so far. In addition, RAPD analyses were performed using 1,200 decamer primers. Twenty-three primers had polymorphic amplification products, differentiating the bulks, and could therefore be mapped. The hybridization of the marker HP4 against a BAC library resulted in three positive clones. The overlapping end of the smallest clone was used to get a new hybridization against the BAC library.
Background: More than 70 cytoplasmic male sterility (CMS) types have been identified in Helianthu... more Background: More than 70 cytoplasmic male sterility (CMS) types have been identified in Helianthus, but only for less than half of them, research of mitochondrial organization has been conducted. Moreover, complete mitochondrion sequences have only been published for two CMS sources-PET1 and PET2. It has been demonstrated that other sunflower CMS sources like MAX1, significantly differ from the PET1 and PET2 types. However, possible molecular causes for the CMS induction by MAX1 have not yet been proposed. In the present study, we have investigated structural changes in the mitochondrial genome of HA89 (MAX1) CMS sunflower line in comparison to the fertile mitochondrial genome. Results: Eight significant major reorganization events have been determined in HA89 (MAX1) mtDNA: one 110 kb inverted region, four deletions of 439 bp, 978 bp, 3183 bp and 14,296 bp, respectively, and three insertions of 1999 bp, 5272 bp and 6583 bp. The rearrangements have led to functional changes in the mitochondrial genome of HA89 (MAX1) resulting in the complete elimination of orf777 and the appearance of new ORFs-orf306, orf480, orf645 and orf1287. Aligning the mtDNA of the CMS sources PET1 and PET2 with MAX1 we found some common reorganization features in their mitochondrial genome sequences. Conclusion: The new open reading frame orf1287, representing a chimeric atp6 gene, may play a key role in MAX1 CMS phenotype formation in sunflower, while the contribution of other mitochondrial reorganizations seems to appear negligible for the CMS development.
Trees are capable of tremendous architectural plasticity, allowing them to maximize their light e... more Trees are capable of tremendous architectural plasticity, allowing them to maximize their light exposure under highly competitive environments. One key component of tree architecture is the branch angle, yet little is known about the molecular basis for the spatial patterning of branches in trees. Here, we report the identification of a candidate gene for the br mutation in Prunus persica (peach) associated with vertically oriented growth of branches, referred to as 'pillar' or 'broomy'. Ppa010082, annotated as hypothetical protein in the peach genome sequence, was identified as a candidate gene for br using a next generation sequence-based mapping approach. Sequence similarity searches identified rice TAC1 (tiller angle control 1) as a putative ortholog, and we thus named it PpeTAC1. In monocots, TAC1 is known to lead to less compact growth by increasing the tiller angle. In Arabidopsis, an attac1 mutant showed more vertical branch growth angles, suggesting that the gene functions universally to promote the horizontal growth of branches. TAC1 genes belong to a gene family (here named IGT for a shared conserved motif) found in all plant genomes, consisting of two clades: one containing TAC1-like genes; the other containing LAZY1, which contains an EAR motif, and promotes vertical shoot growth in Oryza sativa (rice) and Arabidopsis through influencing polar auxin transport. The data suggest that IGT genes are ancient, and play conserved roles in determining shoot growth angles in plants. Understanding how IGT genes modulate branch angles will provide insights into how different architectural growth habits evolved in terrestrial plants.
Climate changes leading to increasingly longer seasonal drought periods in large parts of the wor... more Climate changes leading to increasingly longer seasonal drought periods in large parts of the world increase the necessity for breeding drought-tolerant crops. Cultivated potato (Solanum tuberosum), the third most important vegetable crop worldwide, is regarded as drought-sensitive due to its shallow root architecture. Two German tetraploid potato cultivars differing in drought tolerance and their F1-progeny were evaluated under various drought scenarios. Bulked segregant analyses were combined with whole-genome sequencing (BSA-Seq) using contrasting bulks of drought-tolerant and drought-sensitive F1-clones. Applying QTLseqr, 15 QTLs comprising 588,983 single nucleotide polymorphisms (SNPs) in 2325 genes associated with drought stress tolerance were identified. SeqSNP analyses in an association panel of 34 mostly starch potato varieties using 1-8 SNPs for each of 188 selected genes narrowed the number of candidate genes down to 10. In addition, ent-kaurene synthase B was the only gene present under QTL 10. Eight of the identified genes (StABP1,
ABSTRACT Sclerotinia sclerotiorum is considered the most devastating pathogen of sunflower grown ... more ABSTRACT Sclerotinia sclerotiorum is considered the most devastating pathogen of sunflower grown in humid environments. In this study, progenies of partial hybrids between Helianthus maximiliani, a wild species that has been shown to be resistant to S. sclerotiorum, and H. annuus were characterized by amplified fragment length polymorphism (AFLP) analysis to identify whether there are introgressions from H. maximiliani into the cultivated sunflower at the molecular level. Wild species-specific fragments as well as fragments not found in either parent were detected. Progenies tended to cluster together according to the original partial hybrids in the dendrogram by the use of bootstrap procedures. The progenies were studied for their reaction to S. sclerotiorum using artificial inoculation of sunflower heads. Some of the progenies showed a higher level of resistance compared with resistant inbred lines. It was possible to identify two AFLP-fragments which seem to be linked to Sclerotinia resistance.
Current plant science and biotechnology in agriculture, 1997
Cultivated sunflower (Helianthus annuus L.) is one of the most important oil crops of the world. ... more Cultivated sunflower (Helianthus annuus L.) is one of the most important oil crops of the world. Its seed oil can be used for human consumption as well as a raw material for oleochemistry. It can also be used as a substitute for mineral oil in various applications, such as fuels, lubricants or oils for hydraulic systems.
The SF21 proteins were originally identified in sunflower pollen and in the stigmatic and transmi... more The SF21 proteins were originally identified in sunflower pollen and in the stigmatic and transmitting tissues of sunflower pistils [Kräuter
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Molecular characterization of 28 CMS sources and the fertile cytoplasm of H. annuus in sunflower ... more Molecular characterization of 28 CMS sources and the fertile cytoplasm of H. annuus in sunflower demonstrated that cytoplasms different by their origin show a considerable similarity that cannot be expected from their pedigree. Cluster analysis using the UPGMA method allowed differentiating 10 mitochondrial (mt) types based on RFLP data. Characteristic proteins specific for one or more CMS sources could be identified which correspond to the mt types. In addition, the data obtained on fertility restoration for a subset of nine new CMS sources support the classification of the cytoplasms made on mtDNA level as demonstrated in the UPGMA dendrogram. A map-based cloning approach is followed for the isolation of the restorer gene Rf1, which restores pollen fertility in hybrids based on PET1. Markers closely linked to the restorer gene could be identified using AFLP and RAPD technologies. A bacterial artificial chromosome (BAC) library was constructed using the sunflower restorer line RHA325 and pBeloBAC11 as vector. The first sunflower BAC library corresponds to 1.7 haploid genome equivalents (104,736 clones, average insert size approx. 50 kb). Use of STS markers, which had been developed from RAPD markers, allowed to identify three BAC clones by colony hybridization against high density filters. DNA fingerprinting using HindIII allowed to build a contig for the restorer locus Rf1.
International Journal of Molecular Sciences, Jun 7, 2021
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
ABSTRACT The development of commercial sunflower hybrids based on new CMS sources is of special i... more ABSTRACT The development of commercial sunflower hybrids based on new CMS sources is of special interest for reducing the potential risk of vulnerability to pathogens and for increasing genetic diversity. From 263 test crosses involving nine new CMS sources, i.e. ANL1, ANL2, MAX1, PEF1, PET2, ANN1, ANN2, ANNS and ANN4, five lines were selected as potential restorers for PEF1, PET2 and ANN4. In test crosses between all nine CMS sources and these five restorer lines evaluated in 2 years, seven fully restored hybrids could be identified. These hybrids, based on ANL1, ANL2, MAX1, PEF1, PET2, and ANN4, showed good agronomic performance for plant height, days to flowering, maturity and oil content. Segregation analyses of the F2 populations indicate that a single dominant restorer gene was sufficient to restore pollen production of hybrids based on ANL2, PEF1 and PET2. For restoration of ANN4, two dominant complementary genes are required. In restoration of fertility in the crosses of ANL1 and MAX1 investigated, two dominant genes are involved each of which on its own allows the production of fertile plants.
Page 1. Development of sequence-tagged site markers linked to the pillar growth type in peach (Pr... more Page 1. Development of sequence-tagged site markers linked to the pillar growth type in peach (Prunus persica) Osama SAJER 1 , Ralph SCORZA 2 , Chris DARDICK 2 , Tetyana ZHEBENTYAYEVA 3 , Albert G. ABBOTT 3 and ... 2003, Cipriani et al. 1999, Dirlewanger et al. ...
Fertility restoration by dominant nuclear genes is essential for hybrid breeding based on cytopla... more Fertility restoration by dominant nuclear genes is essential for hybrid breeding based on cytoplasmic male sterility (CMS) to obtain heterotic effects and high seed yields. In sunflower, only the PET1 sterility inducing cytoplasm has been used in commercial hybrid breeding until now. This particular male sterility was derived from an interspecific hybrid Helianthus petiolaris × H. annuus. For the recent
Systems responses to drought stress of four potato reference cultivars with differential drought ... more Systems responses to drought stress of four potato reference cultivars with differential drought tolerance (Solanum tuberosum L.) were investigated by metabolome profiling and RNA sequencing. Systems analysis was based on independent field and greenhouse trials. Robust differential drought responses across all cultivars under both conditions comprised changes of proline, raffinose, galactinol, arabitol, arabinonic acid, chlorogenic acid and 102 transcript levels. The encoded genes contained a high proportion of heat shock proteins and proteins with signalling or regulatory functions, for example, a homolog of abscisic acid receptor PYL4. Constitutive differences of the tolerant compared with the sensitive cultivars included arbutin, octopamine, ribitol and 248 transcripts. The gene products of many of these transcripts were pathogen response related, such as receptor kinases, or regulatory proteins, for example, a homolog of the Arabidopsis FOUR LIPS MYB-regulator of stomatal cell proliferation. Functional enrichment analyses imply heat stress as a major acclimation component of potato leaves to long-term drought stress. Enhanced heat stress during drought can be caused by loss of transpiration cooling. This effect and CO 2 limitation are the main consequences of drought-induced or abscisic acidinduced stomatal closure. Constitutive differences in metabolite and transcript levels between tolerant and sensitive cultivars indicate interactions of drought tolerance and pathogen resistance in potato.
The mmt thorouJ!h~l' im•t•sti}!ated C'.\JS ~l11t! in sw!flower i.~ the l'l:'T/ (or Leclercq) c:vt... more The mmt thorouJ!h~l' im•t•sti}!ated C'.\JS ~l11t! in sw!flower i.~ the l'l:'T/ (or Leclercq) c:vtoplasm. The tii'J!tlllization oft he mtfJX•lt?(male sterile (/'/:'TI c:rtoplasm) mulji•rtile litu•s d(fli'n on~v hy tm II kh itll'ersion and 11 5 kh insertion. Due to thi.~ in~ertionam•w IIJI<'III'<'adingfiwue. orfl/521, is ctwtted i11the 3'~/lankinJ! re~:io11 t?(the atpA ~:ene. 71te
In sunflower, commercial hybrid breeding is based on a single CMSinducing cytoplasm, the so-calle... more In sunflower, commercial hybrid breeding is based on a single CMSinducing cytoplasm, the so-called PET1 cytoplasm. The introduction of one dominant, nuclear-encoded restorer gene (Rf1) is in most cases sufficient for fertility restoration. Little has been learned so far about the mode of action of the restorer gene Rf1. For map-based cloning of the restorer gene Rf1, an F 2 population of the cross RHA325 (cms) x HA342 has been used. The χ²-test confirmed segregation for one dominant gene which corresponds to Rf1. For the AFLP analyses 256 EcoRI/MseI primer combinations have been used so far. In addition, RAPD analyses were performed using 1,200 decamer primers. Twenty-three primers had polymorphic amplification products, differentiating the bulks, and could therefore be mapped. The hybridization of the marker HP4 against a BAC library resulted in three positive clones. The overlapping end of the smallest clone was used to get a new hybridization against the BAC library.
Background: More than 70 cytoplasmic male sterility (CMS) types have been identified in Helianthu... more Background: More than 70 cytoplasmic male sterility (CMS) types have been identified in Helianthus, but only for less than half of them, research of mitochondrial organization has been conducted. Moreover, complete mitochondrion sequences have only been published for two CMS sources-PET1 and PET2. It has been demonstrated that other sunflower CMS sources like MAX1, significantly differ from the PET1 and PET2 types. However, possible molecular causes for the CMS induction by MAX1 have not yet been proposed. In the present study, we have investigated structural changes in the mitochondrial genome of HA89 (MAX1) CMS sunflower line in comparison to the fertile mitochondrial genome. Results: Eight significant major reorganization events have been determined in HA89 (MAX1) mtDNA: one 110 kb inverted region, four deletions of 439 bp, 978 bp, 3183 bp and 14,296 bp, respectively, and three insertions of 1999 bp, 5272 bp and 6583 bp. The rearrangements have led to functional changes in the mitochondrial genome of HA89 (MAX1) resulting in the complete elimination of orf777 and the appearance of new ORFs-orf306, orf480, orf645 and orf1287. Aligning the mtDNA of the CMS sources PET1 and PET2 with MAX1 we found some common reorganization features in their mitochondrial genome sequences. Conclusion: The new open reading frame orf1287, representing a chimeric atp6 gene, may play a key role in MAX1 CMS phenotype formation in sunflower, while the contribution of other mitochondrial reorganizations seems to appear negligible for the CMS development.
Trees are capable of tremendous architectural plasticity, allowing them to maximize their light e... more Trees are capable of tremendous architectural plasticity, allowing them to maximize their light exposure under highly competitive environments. One key component of tree architecture is the branch angle, yet little is known about the molecular basis for the spatial patterning of branches in trees. Here, we report the identification of a candidate gene for the br mutation in Prunus persica (peach) associated with vertically oriented growth of branches, referred to as 'pillar' or 'broomy'. Ppa010082, annotated as hypothetical protein in the peach genome sequence, was identified as a candidate gene for br using a next generation sequence-based mapping approach. Sequence similarity searches identified rice TAC1 (tiller angle control 1) as a putative ortholog, and we thus named it PpeTAC1. In monocots, TAC1 is known to lead to less compact growth by increasing the tiller angle. In Arabidopsis, an attac1 mutant showed more vertical branch growth angles, suggesting that the gene functions universally to promote the horizontal growth of branches. TAC1 genes belong to a gene family (here named IGT for a shared conserved motif) found in all plant genomes, consisting of two clades: one containing TAC1-like genes; the other containing LAZY1, which contains an EAR motif, and promotes vertical shoot growth in Oryza sativa (rice) and Arabidopsis through influencing polar auxin transport. The data suggest that IGT genes are ancient, and play conserved roles in determining shoot growth angles in plants. Understanding how IGT genes modulate branch angles will provide insights into how different architectural growth habits evolved in terrestrial plants.
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