xi, 138 Pags.- 24 Graf.- 10 Figs.- 7 Tabls. Tesis doctoral elaborada en el Servicio de Investigac... more xi, 138 Pags.- 24 Graf.- 10 Figs.- 7 Tabls. Tesis doctoral elaborada en el Servicio de Investigacion Agraria, dependiente de la Diputacion General de Aragon, y dirigida por los Drs. Maria Herrero Romero (EEAD-CSIC) y Jose Ignacio Hormaza Urroz (ISHM-CSIC).
El cuajado de fruto es vulnerable a las condiciones climaticas durante la floracion. Se sabe que ... more El cuajado de fruto es vulnerable a las condiciones climaticas durante la floracion. Se sabe que el nivel de cuajado se puede reducir sensiblemente en primaveras frias. Sin embargo, la casuistica acumulada sobre bajos cuajados registrados en cerezo en primaveras aparentemente "buenas" y calidas nos ha llevado a evaluar el efecto de las altas temperaturas sobre la fase reproductiva y su repercusion en el cuajado de fruto en esta especie. La colocacion de una cabina de plastico sobre los arboles produce un aumento medio de la temperatura del orden de 3oC, que es suficiente para reducir claramente el nivel de cuajado. Las altas temperaturas aceleran el crecimiento de los tubos polinicos, pero tambien aceleran la degeneracion tanto de los estigmas como de los ovulos. Aunque la temperatura no puede controlarse facilmente, una adecuada polinizacion de las flores desde los primeros momentos de su apertura puede mitigar estos efectos.
In this introductory chapter, we describe male germline development in plants taking Arabidopsis ... more In this introductory chapter, we describe male germline development in plants taking Arabidopsis thaliana as a reference species. We first describe the transition from sporophytic to germline development, then microsporogenesis including meiosis, followed by male gametophyte development prior to pollination, and finally the progamic phase culminating in double fertilization, which leads to the formation of the embryo and the endosperm. For detailed information on some of these processes or on the molecular underpinning of certain fate transitions, we refer the reader to recent reviews. An important but often neglected aspect of male gametophyte development is the formation of the unique pollen cell wall. In contrast to that of other plant cells, the pollen cell wall is composed of two principal layers, the intine and exine. While the intine, the inner pecto-cellulosic cell wall layer, is biochemically and structurally similar to a "classical" plant cell wall, the exine is a unique composite with sporopollenin as its main component. Biosynthesis of the cell wall is remarkably similar between the spores of mosses and ferns, and pollen of seed plants, although slight differences exist, even between closely related species (reviewed in Wallace et al., AoB Plants 2011:plr027, 2011). In the latter sections of this chapter, we will present a brief overview of cell wall development in Arabidopsis pollen, where this aspect has been intensively studied.
Self-incompatibility in Prunus species is governed by a single locus consisting of two highly mul... more Self-incompatibility in Prunus species is governed by a single locus consisting of two highly multi-allelic and tightly linked genes, one coding for an F-box protein—i.e., SFB in Prunus- controlling the pollen specificity and one coding for an S-RNase gene controlling the pistil specificity. Genotyping the allelic combination in a fruit tree species is an essential procedure both for cross-based breeding and for establishing pollination requirements. Gel-based PCR techniques using primer pairs designed from conserved regions and spanning polymorphic intronic regions are traditionally used for this task. However, with the great advance of massive sequencing techniques and the lowering of sequencing costs, new genotyping-by-sequencing procedures are emerging. The alignment of resequenced individuals to reference genomes, commonly used for polymorphism detection, yields little or no coverage in the S-locus region due to high polymorphism between different alleles within the same specie...
Dormancy is an adaptive strategy in plants to survive under unfavorable climatic conditions durin... more Dormancy is an adaptive strategy in plants to survive under unfavorable climatic conditions during winter. In temperate regions, most fruit trees need exposure to a certain period of low temperatures to overcome endodormancy. After endodormancy release, exposure to warm temperatures is needed to flower (ecodormancy). Chilling and heat requirements are genetically determined and, therefore, are specific for each species and cultivar. The lack of sufficient winter chilling can cause failures in flowering and fruiting, thereby compromising yield. Thus, the knowledge of the chilling and heat requirements is essential to optimize cultivar selection for different edaphoclimatic conditions. However, the lack of phenological or biological markers linked to the dormant and forcing periods makes it difficult to establish the end of endodormancy. This has led to indirect estimates that are usually not valid in different agroclimatic conditions. The increasing number of milder winters caused by...
There are 7 excel sheets: (1) meteorological data during the first 8 days after pollination. (2) ... more There are 7 excel sheets: (1) meteorological data during the first 8 days after pollination. (2) fruit set analyses registered during the three year. (3) raw and summarized data of S-allele segregations for the first year. (4) raw and summarized data of S-allele segregations for the second year. (5) Summarized data of S-allele segregations for the third year. (6) Raw data of pollen tube growth kinetics and dynamics for the first and second year. (7) Raw data of pollen tube growth kinetics and dynamics for the third year
Homomorphic self-incompatibility is a well-studied example of a physiological process that is tho... more Homomorphic self-incompatibility is a well-studied example of a physiological process that is thought to increase population diversity and reduce the expression of inbreeding depression. Whereas theoretical models predict the presence of a large number of S-haplotypes with equal frequencies at equilibrium, unequal allele frequencies have been repeatedly reported and attributed to sampling effects, population structure, demographic perturbation, sheltered deleterious mutations or selection pressure on linked genes. However, it is unclear to what extent unequal segregations are the results of gametophytic or sexual selection. Although these two forces are difficult to disentangle, testing S-alleles in the offspring of controlled crosses provides an opportunity to separate these two phenomena. In this work, segregation and transmission of S-alleles have been characterized in progenies of mixed donors and fully compatible pollinations under field conditions in Prunus avium. Seed set patterns and pollen performance have also been characterized. The results reveal paternal-specific distorted transmission of S-alleles in most of the crosses. Interestingly, S-allele segregation within any given paternal or maternal S-locus was random. Observations on pollen germination, pollen tube growth rate, pollen tube cohort size, seed set dynamics and transmission patterns strongly suggest post-pollination, prezygotic sexual selection, with male–male competition as the most likely mechanism. According to these results, post-pollination sexual selection takes precedence over frequency-dependent selection in explaining unequal S-haplotype frequencies
In this introductory chapter, we describe male germline development in plants taking Arabidopsis ... more In this introductory chapter, we describe male germline development in plants taking Arabidopsis thaliana as a reference species. We first describe the transition from sporophytic to germline development, then microsporogenesis including meiosis, followed by male gametophyte development prior to pollination, and finally the progamic phase culminating in double fertilization, which leads to the formation of the embryo and the endosperm. For detailed information on some of these processes or on the molecular underpinning of certain fate transitions, we refer the reader to recent reviews. An important but often neglected aspect of male gametophyte development is the formation of the unique pollen cell wall. In contrast to that of other plant cells, the pollen cell wall is composed of two principal layers, the intine and exine. While the intine, the inner pecto-cellulosic cell wall layer, is biochemically and structurally similar to a "classical" plant cell wall, the exine is a unique composite with sporopollenin as its main component. Biosynthesis of the cell wall is remarkably similar between the spores of mosses and ferns, and pollen of seed plants, although slight differences exist, even between closely related species (reviewed in Wallace et al., AoB Plants 2011:plr027, 2011). In the latter sections of this chapter, we will present a brief overview of cell wall development in Arabidopsis pollen, where this aspect has been intensively studied.
xi, 138 Pags.- 24 Graf.- 10 Figs.- 7 Tabls. Tesis doctoral elaborada en el Servicio de Investigac... more xi, 138 Pags.- 24 Graf.- 10 Figs.- 7 Tabls. Tesis doctoral elaborada en el Servicio de Investigacion Agraria, dependiente de la Diputacion General de Aragon, y dirigida por los Drs. Maria Herrero Romero (EEAD-CSIC) y Jose Ignacio Hormaza Urroz (ISHM-CSIC).
El cuajado de fruto es vulnerable a las condiciones climaticas durante la floracion. Se sabe que ... more El cuajado de fruto es vulnerable a las condiciones climaticas durante la floracion. Se sabe que el nivel de cuajado se puede reducir sensiblemente en primaveras frias. Sin embargo, la casuistica acumulada sobre bajos cuajados registrados en cerezo en primaveras aparentemente "buenas" y calidas nos ha llevado a evaluar el efecto de las altas temperaturas sobre la fase reproductiva y su repercusion en el cuajado de fruto en esta especie. La colocacion de una cabina de plastico sobre los arboles produce un aumento medio de la temperatura del orden de 3oC, que es suficiente para reducir claramente el nivel de cuajado. Las altas temperaturas aceleran el crecimiento de los tubos polinicos, pero tambien aceleran la degeneracion tanto de los estigmas como de los ovulos. Aunque la temperatura no puede controlarse facilmente, una adecuada polinizacion de las flores desde los primeros momentos de su apertura puede mitigar estos efectos.
In this introductory chapter, we describe male germline development in plants taking Arabidopsis ... more In this introductory chapter, we describe male germline development in plants taking Arabidopsis thaliana as a reference species. We first describe the transition from sporophytic to germline development, then microsporogenesis including meiosis, followed by male gametophyte development prior to pollination, and finally the progamic phase culminating in double fertilization, which leads to the formation of the embryo and the endosperm. For detailed information on some of these processes or on the molecular underpinning of certain fate transitions, we refer the reader to recent reviews. An important but often neglected aspect of male gametophyte development is the formation of the unique pollen cell wall. In contrast to that of other plant cells, the pollen cell wall is composed of two principal layers, the intine and exine. While the intine, the inner pecto-cellulosic cell wall layer, is biochemically and structurally similar to a "classical" plant cell wall, the exine is a unique composite with sporopollenin as its main component. Biosynthesis of the cell wall is remarkably similar between the spores of mosses and ferns, and pollen of seed plants, although slight differences exist, even between closely related species (reviewed in Wallace et al., AoB Plants 2011:plr027, 2011). In the latter sections of this chapter, we will present a brief overview of cell wall development in Arabidopsis pollen, where this aspect has been intensively studied.
Self-incompatibility in Prunus species is governed by a single locus consisting of two highly mul... more Self-incompatibility in Prunus species is governed by a single locus consisting of two highly multi-allelic and tightly linked genes, one coding for an F-box protein—i.e., SFB in Prunus- controlling the pollen specificity and one coding for an S-RNase gene controlling the pistil specificity. Genotyping the allelic combination in a fruit tree species is an essential procedure both for cross-based breeding and for establishing pollination requirements. Gel-based PCR techniques using primer pairs designed from conserved regions and spanning polymorphic intronic regions are traditionally used for this task. However, with the great advance of massive sequencing techniques and the lowering of sequencing costs, new genotyping-by-sequencing procedures are emerging. The alignment of resequenced individuals to reference genomes, commonly used for polymorphism detection, yields little or no coverage in the S-locus region due to high polymorphism between different alleles within the same specie...
Dormancy is an adaptive strategy in plants to survive under unfavorable climatic conditions durin... more Dormancy is an adaptive strategy in plants to survive under unfavorable climatic conditions during winter. In temperate regions, most fruit trees need exposure to a certain period of low temperatures to overcome endodormancy. After endodormancy release, exposure to warm temperatures is needed to flower (ecodormancy). Chilling and heat requirements are genetically determined and, therefore, are specific for each species and cultivar. The lack of sufficient winter chilling can cause failures in flowering and fruiting, thereby compromising yield. Thus, the knowledge of the chilling and heat requirements is essential to optimize cultivar selection for different edaphoclimatic conditions. However, the lack of phenological or biological markers linked to the dormant and forcing periods makes it difficult to establish the end of endodormancy. This has led to indirect estimates that are usually not valid in different agroclimatic conditions. The increasing number of milder winters caused by...
There are 7 excel sheets: (1) meteorological data during the first 8 days after pollination. (2) ... more There are 7 excel sheets: (1) meteorological data during the first 8 days after pollination. (2) fruit set analyses registered during the three year. (3) raw and summarized data of S-allele segregations for the first year. (4) raw and summarized data of S-allele segregations for the second year. (5) Summarized data of S-allele segregations for the third year. (6) Raw data of pollen tube growth kinetics and dynamics for the first and second year. (7) Raw data of pollen tube growth kinetics and dynamics for the third year
Homomorphic self-incompatibility is a well-studied example of a physiological process that is tho... more Homomorphic self-incompatibility is a well-studied example of a physiological process that is thought to increase population diversity and reduce the expression of inbreeding depression. Whereas theoretical models predict the presence of a large number of S-haplotypes with equal frequencies at equilibrium, unequal allele frequencies have been repeatedly reported and attributed to sampling effects, population structure, demographic perturbation, sheltered deleterious mutations or selection pressure on linked genes. However, it is unclear to what extent unequal segregations are the results of gametophytic or sexual selection. Although these two forces are difficult to disentangle, testing S-alleles in the offspring of controlled crosses provides an opportunity to separate these two phenomena. In this work, segregation and transmission of S-alleles have been characterized in progenies of mixed donors and fully compatible pollinations under field conditions in Prunus avium. Seed set patterns and pollen performance have also been characterized. The results reveal paternal-specific distorted transmission of S-alleles in most of the crosses. Interestingly, S-allele segregation within any given paternal or maternal S-locus was random. Observations on pollen germination, pollen tube growth rate, pollen tube cohort size, seed set dynamics and transmission patterns strongly suggest post-pollination, prezygotic sexual selection, with male–male competition as the most likely mechanism. According to these results, post-pollination sexual selection takes precedence over frequency-dependent selection in explaining unequal S-haplotype frequencies
In this introductory chapter, we describe male germline development in plants taking Arabidopsis ... more In this introductory chapter, we describe male germline development in plants taking Arabidopsis thaliana as a reference species. We first describe the transition from sporophytic to germline development, then microsporogenesis including meiosis, followed by male gametophyte development prior to pollination, and finally the progamic phase culminating in double fertilization, which leads to the formation of the embryo and the endosperm. For detailed information on some of these processes or on the molecular underpinning of certain fate transitions, we refer the reader to recent reviews. An important but often neglected aspect of male gametophyte development is the formation of the unique pollen cell wall. In contrast to that of other plant cells, the pollen cell wall is composed of two principal layers, the intine and exine. While the intine, the inner pecto-cellulosic cell wall layer, is biochemically and structurally similar to a "classical" plant cell wall, the exine is a unique composite with sporopollenin as its main component. Biosynthesis of the cell wall is remarkably similar between the spores of mosses and ferns, and pollen of seed plants, although slight differences exist, even between closely related species (reviewed in Wallace et al., AoB Plants 2011:plr027, 2011). In the latter sections of this chapter, we will present a brief overview of cell wall development in Arabidopsis pollen, where this aspect has been intensively studied.
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