Male and female synchrony and the regulation of mating in flowering plants

Successful mating clearly requires synchronous development of the male and female sexual organs. Evidence is accumulating that this synchrony of development also persists after pollination, with both pollen and pistil following complex, but highly integrated developmental pathways. The timing of the male–female interaction is crucial for the pistil, which, far from being a mature passive structure, is engaged in a continuing programme of development: only being receptive to the advances of the pollen for a relatively short window of time. This developmental programme is most conspicuous in the ovary, and this review focuses on the interaction between the male and female tissues in this structure. The review first considers pollen tube development in the ovary, concentrating of the mechanisms by which its growth is modulated at various control points associated with structures within the ovary. Second, alterations to this ‘normal’ developmental programme are reviewed and considered in the context of a breakdown of developmental synchrony. Finally, the consequences of male–female developmental synchrony and asynchrony are explored. Clearly, a synchronous male–female relationship leads to a successful fertilization. However, lack of synchrony also occurs, and could emerge as a powerful tool to investigate the regulation of mating.

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Flora’s Secret Gardens

10.1093/oso/9780190490263.003.0018 ◽

2018 ◽

Author(s):

Lincoln Taiz ◽

Lee Taiz

Keyword(s):

Pollen Tube ◽

Embryo Sac ◽

Flowering Plants ◽

Sexual Stage ◽

Male And Female ◽

Plant Kingdom ◽

Asexual Spore ◽

The Rose ◽

Plant Sex ◽

Alternation Of Generations

Wilhelm Hofmeister established the unity of the Plant Kingdom through the discovery of Alternation of Generations. In both cryptogams and flowering plants a diploid asexual stage, or sporophyte, alternates with a haploid sexual stage. Thus the flower is not the true sexual stage, but rather the asexual spore-producing stage. The main difference between ferns and roses is that the spores of the fern are visible on the undersides of the leaves, while the spores of the rose are concealed within the anthers and ovaries. These spores develop into the actual sexual stage of the spermatophyte, the male and female gametophytes, i.e. the pollen tube and the embryo sac. Hofmeister’s discovery solved of the age-old quandary over plant sex. The sexualists and the asexualists can both claim to have been correct, but it was the sexualists who freed their minds from cultural biases and glimpsed the true sexual nature of plants.

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The regulation of sexual development in plants

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1993.0011 ◽

1993 ◽

Vol 339 (1288) ◽

pp. 147-157 ◽

Cited By ~ 4

Keyword(s):

Growth Regulators ◽

De Novo ◽

Higher Plants ◽

Reproductive Development ◽

Developmental Pathways ◽

Physiological Data ◽

Regulatory Sequences ◽

Homeotic Genes ◽

Self Incompatibility ◽

Male And Female

Plant reproduction comprises an interlocking array of developmental pathways which include the formation of the sexual organs, the generation of germ lines de novo , and the operation of the mechanisms which regulate epigenetic imprinting and the system of self-incompatibility found in m any angiosperms. Little is known of how these processes are regulated at a molecular level, with the exception of the floral organs which are determined by families of homeotic genes operating in a heterochronic fashion. In dioecious and monoecious plants the expression of these ‘floral’ genes must be modulated by sexdeterm ination sequences, situated in some circumstances on sex chromosomes. Older, physiological data indicate that sex can be determined by growth regulators, particularly gibberellic acid (GA) and cytokinins, and it is possible that sex-determination genes establish local concentrations of growth regulators at the apex, which in turn influence the expression of the homeotic floral genes. Evidence from anther development indicates genes involved in differentiation of the male and female germ lines to be regulated by defined promoter, enhancer, and silencer regions, but few data are available on the sequences directing the initiation and regulation of meiosis; certainly parallels can be drawn with similar events in microorganisms, and useful complementation strategies may be devised, but significant differences do exist between yeasts and higher plants suggesting that more appropriate parallels should be drawn with multicellular eukaryotes such as nematodes. The loci involved in epigenetic imprinting and self-incompatibility are important because they affect both male and female developmental pathways. Nothing is known of the regulatory sequences which direct the epigenetic imprinting of the sperm and central cell genomes, but information is becoming available on the promoter regions of the S (incompatibility)-locus. Interestingly, sequences directing expression in male and female tissues are contained within a single 5' stretch within the locus, and these prom oters also induce expression in different cell types in the anther and pistil depending on the type of self-incompatibility involved. Regulation of reproductive development in plants is apparently not very stringent, for there are examples in both male and female germ lines of reversion to an embryonic condition (apomixis and microspore embryogenesis); whether this reflects the highly dedifferentiated state of these cells or differences in the regulation of somatic and reproductive development remains to be determined.

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Gender and the development of conduct disorder

Development and Psychopathology ◽

10.1017/s0954579400004260 ◽

1993 ◽

Vol 5 (1-2) ◽

pp. 65-78 ◽

Cited By ~ 228

Author(s):

Mark Zoccolillo

Keyword(s):

Risk Factors ◽

Conduct Disorder ◽

Internalizing Disorders ◽

Epidemiologic Studies ◽

Base Rate ◽

Developmental Pathways ◽

Statistical Manual ◽

Male And Female ◽

Diagnostic And Statistical Manual ◽

Base Rates

AbstractA discussion of gender and conduct disorder must first answer the basic questions of whether or not there are any differences in prevalence, symptoms, and correlates of conduct disorder by sex. Several epidemiologic studies have found no difference in the prevalence of conduct disorder in adolescence by sex. Correlates of conduct disorder in girls are similar to those in boys (including aggression and internalizing disorders), once base rates of the correlates are accounted for. A major problem in studying conduct disorder in girls is the lack of appropriate criteria; theDiagnostic and Statistical Manual(3rd ed., rev.) criteria are not appropriate for girls. A case is made for sex-specific criteria for conduct disorder that take into account known differences in male and female childhood cultures and base-rate differences in aggression and criminality. Until basic issues of diagnosis and prevalence are resolved, other issues such as risk factors and developmental pathways cannot be successfully addressed.

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Signaling at Physical Barriers during Pollen–Pistil Interactions

International Journal of Molecular Sciences ◽

10.3390/ijms222212230 ◽

2021 ◽

Vol 22 (22) ◽

pp. 12230

Author(s):

Kayleigh J. Robichaux ◽

Ian S. Wallace

Keyword(s):

Pollen Tube ◽

Structural Integrity ◽

Pollen Tubes ◽

Motile Sperm ◽

Double Fertilization ◽

Male And Female ◽

Transmitting Tract ◽

Guidance Cues ◽

Physical Barriers ◽

Stigmatic Papillae

In angiosperms, double fertilization requires pollen tubes to transport non-motile sperm to distant egg cells housed in a specialized female structure known as the pistil, mediating the ultimate fusion between male and female gametes. During this journey, the pollen tube encounters numerous physical barriers that must be mechanically circumvented, including the penetration of the stigmatic papillae, style, transmitting tract, and synergid cells as well as the ultimate fusion of sperm cells to the egg or central cell. Additionally, the pollen tube must maintain structural integrity in these compact environments, while responding to positional guidance cues that lead the pollen tube to its destination. Here, we discuss the nature of these physical barriers as well as efforts to genetically and cellularly identify the factors that allow pollen tubes to successfully, specifically, and quickly circumnavigate them.

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Pollen tube guidance by the female gametophyte

Development ◽

10.1242/dev.124.12.2489 ◽

1997 ◽

Vol 124 (12) ◽

pp. 2489-2498 ◽

Cited By ~ 1

Author(s):

S.M. Ray ◽

S.S. Park ◽

A. Ray

Keyword(s):

Pollen Tube ◽

Long Range ◽

Female Gametophyte ◽

Chromosomal Translocation ◽

Pollen Grains ◽

Pollen Tubes ◽

Flowering Plants ◽

Genetic Studies ◽

Transmitting Tract ◽

Pollen Tube Guidance

In flowering plants, pollen grains germinate on the pistil and send pollen tubes down the transmitting tract toward ovules. Previous genetic studies suggested that the ovule is responsible for long-range pollen tube guidance during the last phase of a pollen tube's journey to the female gametes. It was not possible, however, to unambiguously identify the signaling cells within an ovule: the haploid female gametophyte or the diploid sporophytic cells. In an effort to distinguish genetically between these two possibilities, we have used a reciprocal chromosomal translocation to generate flowers wherein approximately half the ovules do not contain a functional female gametophyte but all ovules contain genotypically normal sporophytic cells. In these flowers, pollen tubes are guided to the normal but not to the abnormal female gametophytes. These results strongly suggest that the female gametophyte is responsible for pollen tube guidance, but leave open the possibility that the gametophyte may accomplish this indirectly through its influence on some sporophytic cells.

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What we have learned from transcript profile analyses of male and female gametes in flowering plants

Science China Life Sciences ◽

10.1007/s11427-010-4033-1 ◽

2010 ◽

Vol 53 (8) ◽

pp. 927-933 ◽

Cited By ~ 4

Author(s):

HaiPing Xin ◽

MengXiang Sun

Keyword(s):

Flowering Plants ◽

Transcript Profile ◽

Male And Female

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Effects of day length on pollen tube elongation, embryo formation and seed development after flowering in quinoa (Chenopodium quinoa Willd.)

Seed Science Research ◽

10.1017/s0960258518000223 ◽

2018 ◽

Vol 28 (4) ◽

pp. 272-276 ◽

Cited By ~ 1

Author(s):

Katsunori Isobe ◽

Hikaru Sugiyama ◽

Katsura Tamamushi ◽

Taito Shimizu ◽

Kana Kobashi ◽

...

Keyword(s):

Pollen Tube ◽

Seed Development ◽

Chenopodium Quinoa ◽

Early Embryo ◽

Flowering Plants ◽

Day Length ◽

Embryo Formation ◽

Pollen Tube Elongation ◽

Number Of Seeds ◽

Seed Diameter

AbstractThe objective of this study was to evaluate the effect of day length after flowering on pollen tube elongation, embryo formation and seed development. The quinoa varieties used in this study were Amarilla de Marangani (valley type) and NL-6 (sea-level type). After sowing, the quinoa plants were cultivated in growth cabinets. From sowing to flowering, plants were exposed to a 15 h day length regime. After flowering, the plants were grown under either a 15 h or 11 h day length regime. The elongation of the pollen tube and the formation of the early embryo were not inhibited in either Amarilla de Marangani or NL-6 under the 11 or 15 h day length regimes. Although growth of the embryo in NL-6 was not inhibited by the 15 h day length regime after flowering, the same was not observed in the case for Amarilla de Marangani. In Amarilla de Marangani, seed diameter at 8 and 14 days after flowering under the 11 h day length regime was larger than that of seeds grown under the 15 h day length regime. Thus, the decrease in the number of seeds in Amarilla de Marangani grown under the 15 h day length regime may be caused by the suspension of embryo growth after fertilization.

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