scholarly journals Breeding system and inbreeding depression in the rare orchid, Platanthera praeclara, in a fragmented grassland landscape

Botany ◽  
2018 ◽  
Vol 96 (3) ◽  
pp. 151-159 ◽  
Author(s):  
Steven E. Travers ◽  
Kirk Anderson ◽  
Pati Vitt ◽  
Marion O. Harris
Keyword(s):  
Inbreeding Depression ◽  
Seed Quality ◽  
Detectable Effect ◽  
Plant Fitness ◽  
Cross Pollination ◽  
Self Pollination ◽  
Capsule Production ◽  
Hand Pollination ◽  
Platanthera Praeclara ◽  
Self Compatibility

An important consequence of self-compatibility in plants is that self-pollination can have deleterious effects on plant fitness because of inbreeding. We conducted a hand pollination experiment under field conditions to measure the magnitude of inbreeding depression associated with self-pollination in the rare western prairie fringed-orchid Platanthera praeclara Sheviak and Bowles. By comparing capsules and seeds resulting from cross versus self-pollination treatments, we determined that self-pollination reduces seed quality while having no detectable effect on capsule production or seed numbers. A smaller percentage of seeds resulting from self-pollination contained an embryo (18%) relative to seeds from cross-pollination (46%). Seeds that had an embryo were scored for the size of the embryo, small or large. A smaller proportion of seeds from self-pollination contained a large embryo (75%) relative to seeds from cross-pollination (92%). These results suggest that sexual reproduction and recruitment in this rare plant are dependent on the frequency of pollinator visitations that result in outcrossing.

scholarly journals Autonomous pollination alleviates pollen limitation in the endemic Cienfuegosia yucatanensis Millsp. (Malvaceae)

2020 ◽  
Vol 99 (1) ◽  
pp. 80-91
Author(s):  
Víctor Parra-Tabla ◽  
Conchita Alonso
Keyword(s):  
Seed Production ◽  
Inbreeding Depression ◽  
Seed Weight ◽  
Pollen Limitation ◽  
Pollen Tubes ◽  
Pollen Deposition ◽  
Cross Pollination ◽  
The North ◽  
Hand Pollination ◽  
Self Compatibility

Background: Self-compatibility is common on endemic plant species, but pollen limitation and self-pollination could be risk factors. Study species: The endemic Cienfuegosia yucatanensis (Malvaceae), whose distribution is mainly restricted to the north coast of the peninsula of Yucatán, México. Questions: a) Are flowers of C. yucatanensis autonomous for pollination? b) Are C. yucatanensis fruit or seed-set limited by pollen deposition? and, c) Is there evidence of early inbreeding depression in C. yucatanensis? Study sites and dates: Two sites in the north of the peninsula of Yucatán in a seasonally dry scrubland, in the rainy season of 2013 and 2014. Methods: Number of flowers and fruits were weekly recorded. Flowers were collected to count the number of conspecific pollen load and the number of pollen tubes. Autonomous pollination and pollen limitation were evaluated with a hand-pollination experiment. Inbreeding depression on fruit and seed production, and seed weight was evaluated. Results: Flower and fruit production occur simultaneously and last from August to October. Conspecific pollen deposition on stigmas occurred through the whole flowering season and a maximum of pollen tubes was observed in August. Autonomous pollination treatment lead to similar fruit and seed production than cross-pollination, but open pollination produced significantly more seeds. No significant differences among self- and cross-pollination treatments on fruit and seed production or seed weight, were found.  Conclusions: Our results suggest that self-compatibility combined with a relatively efficient autonomous pollination, are suitable mechanisms for the reproductive assurance in C. yucatanensis, with no apparent effects of early inbreeding depression.

scholarly journals Doing the twist: a test of Darwin's cross-pollination hypothesis for pollinarium reconfiguration

2005 ◽  
Vol 2 (1) ◽  
pp. 65-68 ◽  
Author(s):  
Craig I Peter ◽  
Steven D Johnson
Keyword(s):  
Inbreeding Depression ◽  
Mating Success ◽  
Positive Relationship ◽  
Pollen Dispersal ◽  
Strong Support ◽  
Cross Pollination ◽  
Self Pollination ◽  
Strong Positive Relationship ◽  
Mating Opportunities

Mating success in plants depends largely on the efficiency of pollen dispersal. For hermaphrodite plants, self-pollination, either within or among flowers, can reduce mating opportunities because of pollen and ovule discounting and inbreeding depression. Self-pollination may be particularly detrimental in plants such as orchids and asclepiads that package each flower's pollen into one or more pollinia which, together with accessory structures, comprise a pollinarium. Darwin proposed that physical reconfiguration of pollinaria serves as a mechanism for reducing the likelihood of self-pollination. To be effective, the time taken for pollinarium reconfiguration would need to exceed that spent by a pollinator on a plant. We investigated pollinarium reconfiguration (including pollinarium bending, pollinium shrinking and anther cap retention) in 19 species and found a strong positive relationship between reconfiguration time and the duration of pollinator visits. Reconfiguration times were also consistently longer than pollinator visit times. These results provide strong support for Darwin's idea that this mechanism promotes cross-pollination.

scholarly journals Pollen Paternity Can Affect Kernel Size and Nutritional Composition of Self-Incompatible and New Self-Compatible Almond Cultivars

Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 326
Author(s):  
Wiebke Kämper ◽  
Grant Thorp ◽  
Michelle Wirthensohn ◽  
Peter Brooks ◽  
Stephen J. Trueman
Keyword(s):  
Crop Production ◽  
Nutritional Composition ◽  
Open Pollination ◽  
Kernel Size ◽  
Pollination Services ◽  
Crop Quality ◽  
Pests And Diseases ◽  
Cross Pollination ◽  
Self Pollination ◽  
Self Compatibility

Breeding programs for horticultural tree crops focus on enhancing productivity, including developing tolerance to pests and diseases and improving crop quality. Pollination services are often critical for crop production, and pollen parents can affect crop quality. We often do not know which pollen parents produce highest quality offspring or, in self-compatible cultivars, how much of the crop comes from cross- versus self-pollination. We quantified the proportions of self- and cross-paternity in an open pollination setting of five standard commercial almond cultivars and of six new almond cultivars selected for yield, kernel size, taste or self-compatibility. We assessed how pollination by different parents affected kernel size and nutritional quality. Kernels from most commercial cultivars and from the new cultivars selected for taste and size resulted almost entirely from cross-pollination. Most kernels from the commercial cultivar ‘Price’ resulted from cross-pollination but 21% resulted from self-pollination. In contrast, 48–91% of kernels from the new self-compatible cultivars resulted from self-pollination. Different cross-pollen parents did not greatly affect kernel size or quality. The proportions of self-paternity in the new self-compatible cultivars varied strongly in an open pollination setting suggesting that some cultivars may be good candidates for establishing monovarietal orchards.

Late-acting self-incompatibility in tea plant (Camellia sinensis)

Biologia ◽  
2012 ◽  
Vol 67 (2) ◽  
Author(s):  
Xuan Chen ◽  
Shan Hao ◽  
Li Wang ◽  
Wanping Fang ◽  
Yuhua Wang ◽  
...  
Keyword(s):  
Pollen Tube ◽  
Camellia Sinensis ◽  
Pollen Tubes ◽  
Tea Plant ◽  
The Self ◽  
Self Incompatibility ◽  
Cross Pollination ◽  
Self Pollination ◽  
Hand Pollination ◽  
Pollen Tube Elongation

AbstractThe self-incompatibility of tea plant (Camellia sinensis (L.) O. Kuntze) was studied with the methods of aniline blue fluorescence assay and paraffin sections. The characteristics of pollen tube elongation after hand pollination was analyzed in 4 tea cultivars, including ‘Keemenzhong’, ‘Longjing-changye’, ‘Fuding-dabaicha’ and ‘Yabukita’, under self-pollination and cross-pollination, respectively. Although there were some difference among cultivars, pollen tubes elongated through the style and reach the ovary successfully at 48 h after pollination for both cross- and self-pollen tubes in all the four cultivars of tea. Pollen tubes entered into the ovule micropyles, however, only for cross-pollination, but not for self-pollination. Pollen tubes of selfing plants, failed in fertilizing, seemed have some difficulties to enter the ovule. All of which indicated that the self-incompatibility of tea plant is a late-acting self-incompatibility system (LSI) or an ovarian sterility (OS), in which the self incompatibility was due to none self pollen tube penetrating into the ovule and no fertilization.

scholarly journals Depression by inbreeding after four sucessive self-pollination squash generations

2004 ◽  
Vol 61 (2) ◽  
pp. 224-227 ◽  
Author(s):  
Antonio Ismael Inácio Cardoso
Keyword(s):  
Regression Analysis ◽  
Seed Production ◽  
Inbreeding Depression ◽  
Seed Quality ◽  
Inbreeding Coefficient ◽  
Cucurbita Moschata ◽  
F1 Hybrid ◽  
Self Pollination ◽  
Parental Lines ◽  
Level Effect

The strategy for breeding F1 hybrid squash is to develop parental lines through self-pollination. However, it increases plant mean homozygosis, which is not the natural genetic state of a cross-pollinated species, and can cause "inbreeding depression". The objective of this work was to evaluate this depression with sucessive generations of self-pollination (without selection) in Cucurbita moschata, cv. Piramoita. Populations were obtained from lines with one to four generations of self-pollination (obtained by the SSD method), from the original cv. Piramoita (population S0). Randomized blocks were used with five treatments (different generations of self-pollination - S0 to S4), six replicates and five plants per plot. Regression analysis was made by the Wright inbreeding coefficient (F) to measure the homozygosis level effect on vigor loss. There was a linear reduction of mean weight and fruit length, seed production (number and weight) per fruit with the increase of the homozygosis level; however inbreeding did not affect seed quality (weight of 100 seeds and germination).

scholarly journals Olive Fertility as Affected by Cross-Pollination and Boron

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
A. Spinardi ◽  
D. Bassi
Keyword(s):  
Pollen Germination ◽  
Fruit Set ◽  
Optimal Level ◽  
Lake Area ◽  
Open Pollination ◽  
Cross Pollination ◽  
Self Pollination ◽  
Self Compatibility ◽  
Source Sink

Self-compatibility of local olive (Olea europaeaL.) accessions and of the cultivars “Frantoio” and “Leccino” was investigated in Garda Lake area, northern Italy. Intercompatibility was determined for “Casaliva,” “Frantoio,” and “Leccino,” as well as the effects of foliar Boron applications (0, 262, 525, or 1050 mg·L−1) applied about one week before anthesis on fruit set, shotberry set, and onin vitropollen germination. Following self-pollination, fruit set was significantly lower and the occurrence of shot berries significantly higher than those obtained by open pollination. No significant effect of controlled cross-pollination over self-pollination on fruit set and shotberry set was detectable. B treatments increased significantly fruit set in “Frantoio” and “Casaliva” but not in “Leccino.” B sprays had no effect on shotberry set, suggesting that these parthenocarpic fruits did not strongly compete for resources allocation and did not take advantage of increased B tissue levels. Foliar B application enhancedin vitropollen germination, and the optimal level was higher for pollen germination than for fruit set. Our results highlight the importance of olive cross pollination for obtaining satisfactory fruit set and the beneficial effect of B treatments immediately prior to anthesis, possibly by affecting positively the fertilisation process and subsequent plant source-sink relations linked to fruitlet retention.

scholarly journals Fitness costs of delayed pollination in a mixed-mating plant

2019 ◽  
Vol 124 (5) ◽  
pp. 869-881 ◽  
Author(s):  
Laura S Hildesheim ◽  
Øystein H Opedal ◽  
W Scott Armbruster ◽  
Christophe Pélabon
Keyword(s):  
Inbreeding Depression ◽  
Population Variation ◽  
Mixed Mating ◽  
Reproductive Assurance ◽  
Fitness Costs ◽  
Cross Pollination ◽  
Floral Longevity ◽  
Self Pollination ◽  
Evolutionary Consequences ◽  
Pollinator Declines

Abstract Background and Aims To predict the evolutionary consequences of pollinator declines, we need to understand the evolution of delayed autonomous self-pollination, which is expected to evolve as a mechanism of reproductive assurance when cross-pollination becomes unreliable. This involves estimating the costs of increased levels of selfing as well as those associated with floral senescence. Methods We studied the mechanisms and costs of delayed self-pollination in the mixed-mating vine Dalechampia scandens (Euphorbiaceae) by first assessing among-population variation in herkogamy and dichogamy, which together determine the rate and timing of autonomous self-pollination. We then tested whether floral longevity responds plastically to delayed pollination. Finally, we assessed the costs of delayed self-pollination in terms of seed number and size, explicitly separating inbreeding depression from effects of floral senescence. Key Results Herkogamy varied extensively, while variation in dichogamy was more limited. Unpollinated blossoms increased their longevity, but seed quantity and quality decreased with increasing delays in pollination, independently of inbreeding depression. Conclusions In D. scandens, earlier autonomous selfing is facilitated by reduced herkogamy rather than reduced protogyny, providing reproductive assurance while maintaining the possibility for outcrossing events. Effective early autonomous self-pollination may evolve under reduced cross-pollination reliability in response to costs associated with floral senescence.

Preferential outcrossing in Banksia ilicifolia (Proteaceae)

2005 ◽  
Vol 53 (2) ◽  
pp. 163 ◽  
Author(s):  
Bambang Heliyanto ◽  
Erik J. Veneklaas ◽  
Hans Lambers ◽  
Siegfried L. Krauss
Keyword(s):  
Breeding System ◽  
Fungal Pathogen ◽  
Fruit Set ◽  
Pollen Limitation ◽  
Genetic Load ◽  
Open Pollination ◽  
Self Pollination ◽  
Hand Pollination ◽  
Self Compatibility ◽  
Non Local

The breeding system of Banksia ilicifolia was assessed by performing controlled hand-pollination manipulations on flowers in a natural population in Perth, Western Australia. The percentage of 2000 flowers per treatment converted to fruits and seeds was assessed across 24 recipient plants following (1) self-pollination, (2) local outcross pollination (same population), (3) non-local outcross pollination (pollen sourced from another population 30 km away), (4) unpollinated but bagged flowers and (5) unpollinated, unbagged flowers (natural pollination). The relative performance of the resulting seeds was assessed by seed weight, germination rates and, in an unplanned component of the study, resistance to a fungal pathogen. The percentage of flowers converted to fruits following self-pollination was low (0.9%), but demonstrated self-compatibility. Fruit set following cross-pollinations (3.6 and 3.3% for non-local and local crosses, respectively) was significantly greater than that following self-pollination, open-pollination (0.4%) and autogamous (0.04%) treatments. Low fruit set for open-pollinated flowers, compared with self- and outcross-pollination treatments, suggests pollen limitation. Pollen tubes were observed in 15 and 20% of upper styles of flowers hand-pollinated with self and local outcross pollen, respectively. Seed germination was dependent on the source of pollen, where fewer selfed seeds germinated (37%) than did both non-local and local outcrossed seeds (83 and 91%, respectively). Selfed seedlings showed poorer survival (33.3%) following fungal attack than both non-local and local outcrossed seeds (69.2 and 68.5%, respectively). Only 13% of selfed seeds survived to be 2-month-old seedlings, compared with 63% for non-local and 57% for local outcrossed seeds. Ultimately, for 2000 flowers hand-pollinated with self pollen, only three seedlings survived to an age of 16 weeks, compared with 37 and 45 seedlings for local-cross and non-local cross treatments on 2000 hand-pollinated flowers, respectively. These results indicate that in this population, B. ilicifolia is self-compatible, but preferentially outcrossing, with strong early acting inbreeding depression. Consequently, the breeding system of B. ilicifolia promotes the maintenance of genetic variation and a high genetic load.

Floral traits, pollination ecology and breeding system of three Clematis species (Ranunculaceae) in Yunnan province, southwestern China

2010 ◽  
Vol 58 (2) ◽  
pp. 115 ◽  
Author(s):  
Nan Jiang ◽  
Wen-Bin Yu ◽  
Hong-Zhe Li ◽  
Kai-Yun Guan
Keyword(s):  
Inbreeding Depression ◽  
Breeding System ◽  
Pollen Limitation ◽  
Mating Strategies ◽  
Breeding Systems ◽  
Floral Traits ◽  
Pollination Syndrome ◽  
Self Pollination ◽  
Hand Pollination ◽  
Integrative Study

Flowers of Clematis display showy corollas and diversified shapes. This diversity motivates study of adaptive evolution of flower–pollinator interactions and the functional association between floral traits and plant mating strategies. An integrative study was undertaken, which focused on pollination and reproductive biology of three species representing all three floral types of Clematis. Floral traits were measured, and pollinator assemblages were observed in the field. Bagging, hand-pollination and removal treatments were used to examine breeding systems. The inbreeding depression and pollen limitation were estimated by fruit-set and seed production obtained from pollination treatments. Their floral traits are distinctly different, but are highly associated with pollination syndrome and breeding system. Among them, Clematis akebioides and C. rehderiana may be facultative autogamy (the former was delayed selfing, and the later competing selfing), and C. chrysocoma may be nearly obligate outcrossing. These conclusions are reflected in their stamen-pistil ratios. The levels of inbreeding depression are negatively associated with autonomous self-pollination. Evolution of self-pollination in C. akebioides and C. rehderiana, and pollen limitation in reproduction of the three Clematis species are discussed. This present study, integrating with previous results, will help us to comprehensively recognise and understand the pollination system and reproductive characteristics of Clematis.

scholarly journals Effects of Self-pollination and Cross-pollination of Vaccinium darrowii (Ericaceae) and Other Low-chill Blueberries

HortScience ◽  
2009 ◽  
Vol 44 (6) ◽  
pp. 1538-1541 ◽  
Author(s):  
Dario J. Chavez ◽  
Paul M. Lyrene
Keyword(s):  
Fruit Set ◽  
Self Incompatibility ◽  
Cross Pollination ◽  
Self Pollination ◽  
Self Compatibility ◽  
Southern Highbush ◽  
Wild Blueberry

Partial to complete self-incompatibility is normal in most Vaccinium L. (Ericaceae) species. Wild blueberry plants of several Florida provenances and species were self- and cross-pollinated in a greenhouse free of pollinators. Fruit set of V. darrowii Camp (2x), V. corymbosum L. (4x), V. arboreum Marsh (2x), and F1 (V. darrowii × V. corymbosum) hybrids was higher after cross-pollination than after self-pollination. Partial to complete self-incompatibility was present in V. darrowii, V. corymbosum, and their tetraploid F1 hybrids. The three V. arboreum clones tested were fully self-incompatible. Intra- and interpopulation crosses in V. corymbosum, V. darrowii, and V. darrowii × V. corymbosum hybrids were highly successful, and self-pollination reduced all fertility parameters. Advanced selections of V. corymbosum were the most self-compatible clones tested, possibly because self-compatibility has been increased by breeders selecting for reliable fruit set in large fields planted with one or a few clones. One southern highbush selection and two F1 hybrids had fruit set of more than 70% after self-pollination. These plants could be potentially used to breed plants that could be planted in single blocks providing reliable yield.

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