Stigma receptivity, mode of reproduction, and mating system in Mesosetum chaseae Luces (Poaceae), a native grass of the Brazilian Pantanal

Controlled pollination experiments were conducted on Acrotriche serrulata R.Br. (Ericaceae) to determine the mating system for this species. Pollen viability and stigma receptivity were investigated to ensure effective timing and sourcing of material for maximum fertilisation. Stigmas were found to be receptive in mature buds, with receptivity maintained while nectar remained within the corolla tube. Germination testing showed that pollen from within mature buds was viable. The mating system of A. serrulata was found to be predominantly outcrossing, with 49.8% of cross-pollinated flowers developing to fruit, compared with 8.7% of self-pollinated flowers. Seed viability did not differ significantly between fruits produced by cross-pollination and those produced by self-pollination, although this may be attributable to low sample sizes available for self-pollinated fruits. These results in combination with morphological features of the flower suggest that a pollinator is required for this species.

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Can Sexual Selection Cause Divergence in Mating System-Related Floral Traits?

10.1101/513481 ◽

2019 ◽

Author(s):

Åsa Lankinen ◽

Maria Strandh

Keyword(s):

Sexual Selection ◽

Mating System ◽

Experimental Evolution ◽

Seed Set ◽

Pollen Competition ◽

Floral Traits ◽

Mixed Mating ◽

Stigma Receptivity ◽

Source Line ◽

Outcrossing Species

AbstractPremise of the ResearchThe wide diversity of floral traits seen among plants is shaped by neutral and selective evolutionary processes. In outcrossing species, sexual selection from competing pollen donors is expected to be important for shaping mating system-related traits but empirical evidence is scarce. In a previous evaluation of experimental evolution lines crossed with either one or two pollen donors (monogamous, M, or polyandrous, P, lines) at early floral stages in mixed-mating Collinsia heterophylla (Plantaginaceae), P showed enhanced pollen competitive ability and reduced maternal seed set compared to M, in accordance with sexually antagonistic evolution of pollen. Here, we asked whether the presence of sexual selection during pollen competition affect mating system-related floral traits in the same lines.MethodologyWe compared flowering start, timing of anther-stigma contact (as an indication of timing of self-pollination), timing of stigma receptivity and first seed set between M and P, and with a source line, S (starting material). The former three traits are later in outcrossers than in selfers of Collinsia. The latter trait was expected to be earlier in P than in M because of sexual selection for early seed siring of pollen.Pivotal ResultsArtificial polyandry for four generations resulted in later flowering start and later anther-stigma contact in P compared to M, and the latter trait was intermediate in S. Thus, P appeared more ‘outcrossing’ than M. Stigma receptivity did not differ between lines. First seed set was earlier in P than in M, as expected from sexual selection.ConclusionsOur results from C. heterophylla experimental evolution lines suggest that a component of sexual selection during outcross pollination could enhance the patterns of floral divergence commonly found between outcrossers and selfers.

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Geographic variation in floral traits is associated with environmental and genetic differences among populations of the mixed mating species Collinsia heterophylla (Plantaginaceae)

Botany ◽

10.1139/cjb-2016-0014 ◽

2017 ◽

Vol 95 (2) ◽

pp. 121-138 ◽

Cited By ~ 7

Author(s):

Åsa Lankinen ◽

Josefin A. Madjidian ◽

Stefan Andersson

Keyword(s):

Environmental Factors ◽

Mating System ◽

Climatic Factors ◽

Environmental Influence ◽

Genetic Correlations ◽

Flower Size ◽

Floral Traits ◽

Mixed Mating ◽

Floral Trait ◽

Stigma Receptivity

Relatively few studies have investigated how geography, environmental factors, and genetics affect floral trait variation. We used mixed-mating Collinsia heterophylla Buist to explore variation in a suite of floral traits related to mating system in populations representing four geographic regions of California, USA, and relate this variation to geography, climatic factors, and local site characteristics. We evaluated the environmental vs. genetic trait variability in the greenhouse. Stage of anther–stigma contact correlated positively with temperature, stage of stigma receptivity was negatively associated with vegetation cover, and flower size differed among populations without any clear relation to environmental factors. Greenhouse data indicated heritability for stage of anther–stigma contact, flower size, and time to flowering, and positive correlations between field and greenhouse for stage of stigma receptivity and flower size; however, stage of anther–stigma contact showed a high degree of environmental influence. Stage of anther–stigma contact covaried positively with stage of stigma receptivity and flower size across maternal families, indicating genetic correlations between traits. In conclusion, phenotypic floral variation within mixed-mating C. heterophylla is mostly determined by a genetic component. Geography, environment, and genetics affect traits differently, suggesting that ecological and evolutionary processes contribute to shaping variability in mating system-related traits.

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The behavioural and genetic mating system of the sand tiger shark, Carcharias taurus , an intrauterine cannibal

Biology Letters ◽

10.1098/rsbl.2013.0003 ◽

2013 ◽

Vol 9 (3) ◽

pp. 20130003 ◽

Cited By ~ 18

Author(s):

Demian D. Chapman ◽

Sabine P. Wintner ◽

Debra L. Abercrombie ◽

Jimiane Ashe ◽

Andrea M. Bernard ◽

...

Keyword(s):

Mating System ◽

Litter Size ◽

Microsatellite Dna ◽

Mating Systems ◽

Sibling Relationships ◽

Tiger Shark ◽

Mode Of Reproduction ◽

Genetic Monogamy ◽

Genetic Mating System ◽

Carcharias Taurus

Sand tiger sharks ( Carcharias taurus ) have an unusual mode of reproduction, whereby the first embryos in each of the paired uteri to reach a certain size (‘hatchlings’) consume all of their smaller siblings during gestation (‘embryonic cannibalism’ or EC). If females commonly mate with multiple males (‘behavioural polyandry’) then litters could initially have multiple sires. It is possible, however, that EC could exclude of all but one of these sires from producing offspring thus influencing the species genetic mating system (‘genetic monogamy’). Here, we use microsatellite DNA profiling of mothers and their litters ( n = 15, from two to nine embryos per litter) to quantify the frequency of behavioural and genetic polyandry in this system. We conservatively estimate that nine of the females we examined (60%) were behaviourally polyandrous. The genetic mating system was characterized by assessing sibling relationships between hatchlings and revealed only 40 per cent genetic polyandry (i.e. hatchlings were full siblings in 60% of litters). The discrepancy stemmed from three females that were initially fertilized by multiple males but only produced hatchlings with one of them. This reveals that males can be excluded even after fertilizing ova and that some instances of genetic monogamy in this population arise from the reduction in litter size by EC. More research is needed on how cryptic post-copulatory and post-zygotic processes contribute to determining paternity and bridging the behavioural and genetic mating systems of viviparous species.

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Delayed stigma receptivity inCollinsia heterophylla(Plantaginaceae): genetic variation and adaptive significance in relation to pollen competition, delayed self-pollination, and mating-system evolution

American Journal of Botany ◽

10.3732/ajb.94.7.1183 ◽

2007 ◽

Vol 94 (7) ◽

pp. 1183-1192 ◽

Cited By ~ 40

Author(s):

Åsa Lankinen ◽

W. Scott Armbruster ◽

Liv Antonsen

Keyword(s):

Genetic Variation ◽

Mating System ◽

Adaptive Significance ◽

Pollen Competition ◽

Stigma Receptivity ◽

System Evolution ◽

Self Pollination ◽

Mating System Evolution

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Mating system of Thrichomys fosteri in the Brazilian Pantanal: spatial patterns indicate promiscuity

Mammalian Biology ◽

10.1007/s42991-020-00040-y ◽

2020 ◽

Vol 100 (4) ◽

pp. 365-375

Author(s):

Pâmela Antunes ◽

Luiz Gustavo Rodrigues Oliveira-Santos ◽

Thiago Mateus Rocha dos Santos ◽

Jorge Fernando Saraiva de Menezes ◽

Walfrido Moraes Tomas ◽

...

Keyword(s):

Mating System ◽

Spatial Patterns ◽

Brazilian Pantanal

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Mating system of the endangered Haloxylon ammodendron (Amaranthaceae) in the Gurbantunggut desert (China)

Israel Journal of Ecology and Evolution ◽

10.1163/22244662-20191036 ◽

2019 ◽

Vol 65 (1-2) ◽

pp. 37-42

Author(s):

Chaobin Zhou ◽

Wei Gong

Keyword(s):

Mating System ◽

Breeding System ◽

Northwest China ◽

Mixed Mating ◽

Haloxylon Ammodendron ◽

Stigma Receptivity ◽

Mixed Mating System ◽

Plant Remains ◽

Facultative Apomixis ◽

System Characteristics

In the arid region of northwest China, H. ammodendron has become the main pioneer species for the restoration of plant communities. However, the breeding system of the plant remains unknown. The floral dynamics and the breeding system characteristics of H. ammodendron were investigated in this study, using a bagging experiment. The results show that anthesis lasted about 22 d. The longevity of individual flowers was 14.1 d. Stigma receptivity lasted about 6 d and there were relatively long periods for the meeting between stamen and stigma. Anther height was slightly greater than that of the stigma. The outcrossing index was 2 and the pollen-ovule ratio was 64,815. The H. ammodendron mating system can be described as a mixed mating system with facultative apomixis; pollination is not necessary for reproduction. The mixed mating system with facultative apomixis could guarantee the reproductive success of H. ammodendron in severe desert conditions with sparse pollinators.

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