LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 134

Search options

  1. Article ; Online: Flower heterochrony and crop yield.

    Strelin, Marina M / Diggle, Pamela K / Aizen, Marcelo A

    Trends in plant science

    2023  Volume 28, Issue 12, Page(s) 1360–1369

    Abstract: Crop improvement has focused on enhancing yield, nutrient content, harvestability, and stress resistance using a trait-centered reductionist approach. This has downplayed the fact that plants are developmentally integrated and respond coordinately and ... ...

    Abstract Crop improvement has focused on enhancing yield, nutrient content, harvestability, and stress resistance using a trait-centered reductionist approach. This has downplayed the fact that plants are developmentally integrated and respond coordinately and predictably to genetic and environmental variation, with potential consequences for food production. Crop yield, including both fruit/seed production and the possibility of generating hybrid crop varieties, is highly dependent on flower morphology and sex, which, in turn, can be profoundly affected by slight shifts in the timing and rate of flower organ development (i.e., flower heterochrony). We argue that understanding the genetic and environmental bases of flower heterochrony and their effect on flower morphology and sex in cultivated plants and in their wild relatives can facilitate crop improvement.
    MeSH term(s) Flowers/genetics ; Reproduction ; Plants ; Seeds ; Fruit
    Language English
    Publishing date 2023-08-21
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 1305448-x
    ISSN 1878-4372 ; 1360-1385
    ISSN (online) 1878-4372
    ISSN 1360-1385
    DOI 10.1016/j.tplants.2023.07.013
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article ; Online: Reproductive assurance weakens pollinator-mediated selection on flower size in an annual mixed-mating species.

    Teixido, Alberto L / Aizen, Marcelo A

    Annals of botany

    2019  Volume 123, Issue 6, Page(s) 1067–1077

    Abstract: Background and aims: In animal-pollinated plants, direct and indirect selection for large and small flowers in predominantly outcrossing and selfing species, respectively, is a common consequence of pollen limitation (PL). However, many hermaphroditic ... ...

    Abstract Background and aims: In animal-pollinated plants, direct and indirect selection for large and small flowers in predominantly outcrossing and selfing species, respectively, is a common consequence of pollen limitation (PL). However, many hermaphroditic species show a mixed-mating system known as delayed selfing, which provides reproductive assurance (RA) only when outcrossing is not realized. Although RA is expected to reduce pollinator-mediated selection towards larger flowers, the consequences of delayed selfing for selection on flower size in mixed-mating species remain overlooked. We investigated whether RA weakens selection on flower size in Tuberaria guttata, a mixed-mating annual herb.
    Methods: We related pollinator visitation rates to flower size and measured seed production in emasculated, hand cross-pollinated and intact (control) flowers in three natural populations. For each population, we estimated variation in PL and RA across individuals differing in flower size and phenotypic selection on this trait.
    Key results: Pollinator visitation increased and RA decreased with flower size in all populations. Increasing RA diminished but did not fully alleviate PL, because of early-acting inbreeding depression. In the least-visited and most pollen-limited population, RA increased seed production by >200 %, intensely counteracting the strong pollinator-mediated selection for larger corollas. In the most-visited population, however, RA increased seed production by an average of only 9 %. This population exhibited the largest fraction of individuals that showed a decrease in seed production due to selfing and the weakest pollinator-mediated selection on flower size.
    Conclusions: The results suggest that the balance between the extent of RA and outcrossing contributes to determine flower size in mixed-mating systems. Pollinator-mediated selection favours larger flowers by increasing outcrossed seeds, but the benefits of RA greatly lessen this effect, especially under severe conditions of pollen limitation. Our findings also indicate that a mixed-mating system can represent an 'evolutionary trap' under an adequate pollinator supply.
    MeSH term(s) Animals ; Biological Evolution ; Flowers ; Pollen ; Pollination ; Reproduction
    Language English
    Publishing date 2019-01-14
    Publishing country England
    Document type Journal Article
    ZDB-ID 1461328-1
    ISSN 1095-8290 ; 0305-7364
    ISSN (online) 1095-8290
    ISSN 0305-7364
    DOI 10.1093/aob/mcz014
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  3. Article: Niche analyses and the potential distribution of four invasive bumblebees worldwide.

    López-Aguilar, Tania Paola / Montalva, Jose / Vilela, Bruno / Arbetman, Marina P / Aizen, Marcelo A / Morales, Carolina L / Silva, Daniel de Paiva

    Ecology and evolution

    2024  Volume 14, Issue 4, Page(s) e11200

    Abstract: The introduction of bees for agricultural production in distinct parts of the world and poor management have led to invasion processes that affect biodiversity, significantly impacting native species. ... ...

    Abstract The introduction of bees for agricultural production in distinct parts of the world and poor management have led to invasion processes that affect biodiversity, significantly impacting native species. Different
    Language English
    Publishing date 2024-04-01
    Publishing country England
    Document type Journal Article
    ZDB-ID 2635675-2
    ISSN 2045-7758
    ISSN 2045-7758
    DOI 10.1002/ece3.11200
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  4. Article ; Online: Darwin's inflorescence syndrome is indeed associated with bee pollination.

    Strelin, Marina M / da Cunha, Nicolay L / Rubini-Pisano, Aimé / Fornoni, Juan / Aizen, Marcelo A

    Plant reproduction

    2023  Volume 37, Issue 1, Page(s) 37–45

    Abstract: Key message: A relationship between vertical acropetal inflorescences with protandrous flowers and bee pollination was hypothesized by Darwin back in 1877. Here we provide empirical evidence supporting this association across the angiosperms. Plant ... ...

    Abstract Key message: A relationship between vertical acropetal inflorescences with protandrous flowers and bee pollination was hypothesized by Darwin back in 1877. Here we provide empirical evidence supporting this association across the angiosperms. Plant reproduction is not only determined by flower traits but also by the arrangement of flowers within inflorescences. Based on his observations of the orchid Spiranthes autumnalis, Darwin proposed in 1877 that bee-pollinated plants presenting protandrous flowers on vertical acropetal inflorescences, where proximal flowers open first, can exploit the stereotypical foraging behavior of their pollinators (i.e., upward movement through the inflorescence) to promote pollen exportation and reduce self-pollination. In these inflorescences, male-phase flowers lie spatially above female-phase flowers. To examine this untested hypothesis, we compiled literature information from 718 angiosperms species and evaluated the association between vertical acropetal inflorescences with protandrous flowers and bee pollination within a phylogenetic comparative framework. Results reveal that this type of inflorescence is indeed more common in species pollinated by bees. Moreover, this association does not seem to be weakened by the presence of alternative self-pollination avoidance mechanisms, like self-incompatibility, suggesting that this inflorescence type benefits mainly male rather than female fitness. Other inflorescence types placing male-phase flowers above female-phase flowers, e.g., vertical basipetal inflorescences with protogynous flowers, do not provide strong evidence of a differential association with pollination by bees. Female-biased nectar production in vertical acropetal inflorescences with protandrous flowers may reinforce the behavior of bees to fly upwards, rendering Darwin's configuration more adaptive than other inflorescence configurations.
    MeSH term(s) Bees ; Animals ; Pollination ; Inflorescence ; Phylogeny ; Flowers ; Pollen ; Magnoliopsida ; Reproduction
    Language English
    Publishing date 2023-08-30
    Publishing country Germany
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2700598-7
    ISSN 2194-7961 ; 2194-7953
    ISSN (online) 2194-7961
    ISSN 2194-7953
    DOI 10.1007/s00497-023-00480-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  5. Article: The interplay between ovule number, pollination and resources as determinants of seed set in a modular plant.

    Strelin, Marina M / Aizen, Marcelo A

    PeerJ

    2018  Volume 6, Page(s) e5384

    Abstract: Background: A classical dichotomous perspective proposes that either pollination or plant resources limit seed production. However, ovule number could also be limiting when pollination results in complete ovule fertilization and there are more plant ... ...

    Abstract Background: A classical dichotomous perspective proposes that either pollination or plant resources limit seed production. However, ovule number could also be limiting when pollination results in complete ovule fertilization and there are more plant resources available than needed to develop seeds. Moreover, this dichotomous view assumes that all flowers of a plant have equal access to a shared pool of resources, although these are frequently compartmentalized within plant modules, for example, inflorescences. How ovule number, pollination and resources affect seed production in physiologically-compartmentalized rather than physiologically-integrated plants has yet to be explored. We used raspberry (
    Methods: We first assessed if ovule number affected the fraction of ovules that develop into seed (i.e., seed set) and whether this effect related to the extent of physiological integration among flowers within plants. This was achieved by statistically testing predictions on the sign and level of plant organization (i.e., among flowers within inflorescences, among inflorescences within ramets, and among ramets) of the relation between ovule number and seed set given different degrees of physiological integration. We then explored whether the relation between ovule number and seed set was affected by plant age (used here as a surrogate of resource availability) and pollination intensity (open-pollination vs. exclusion).
    Results: Within inflorescences, flowers with more ovules set a larger fraction of seeds. On the other hand, seed set at the inflorescence level was negatively related to the average number of ovules per flower. Seed set increased with ovule number and open-pollination, and decreased with ramet age. However, ovule number explained more variation in seed set than ramet age and pollination treatment. Ramet age affected the strength of the relation of seed set to ovule number, which was stronger in old than young ramets. Pollination did not alter the strength of this relation to any significant extent.
    Discussion: Results reveal the importance of ovule number as an overriding factor affecting seed set. Within inflorescences, resources appear to be differentially allocated to developing fruits from flowers with many ovules. This is consistent with the fact that in the raspberry a large proportion of the carbon invested in fruit development is fixed by the inflorescence subtending leaf. Differential resource allocation to flowers with many ovules is not affected by pollinator exclusion, being stronger in resource-exhausted ramets. This suggests that the effects of pollen limitation and resource allocation are compartmentalized at the inflorescence level. Consequently, modular plants can be viewed as reproductive mosaics where either ovule number, pollination or resources limit the number of seeds set by different flowers, so that improvements in any of them could increase plant seed production.
    Language English
    Publishing date 2018-07-31
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2703241-3
    ISSN 2167-8359
    ISSN 2167-8359
    DOI 10.7717/peerj.5384
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  6. Article: Behavioural responses by a bumble bee to competition with a niche‐constructing congener

    Rosenberger, Nick M. / Aizen, Marcelo A. / Dickson, Rachel G. / Harder, Lawrence D.

    journal of animal ecology. 2022 Mar., v. 91, no. 3

    2022  

    Abstract: While feeding, foragers can alter their environment. Such alteration constitutes ecological niche construction (ENC) if it enables future benefits for the constructor and conspecific individuals. The environmental modification may also affect non‐ ... ...

    Abstract While feeding, foragers can alter their environment. Such alteration constitutes ecological niche construction (ENC) if it enables future benefits for the constructor and conspecific individuals. The environmental modification may also affect non‐constructing, bystander species, especially if they share resources with constructor species. If so, ENC could confer the constructor species a competitive advantage by both enhancing its foraging returns and reducing those of bystander species. Expectations – (E1) ENC frequency should vary positively with the recent and current density of the constructor species, and (E2) constructors should use modifications disproportionately. In contrast, bystanders should (E3) experience intensified competition for the affected resource, and (E4) exhibit diverse, possibly mitigating, responses to ENC, depending on opportunity and relative benefits. We investigated these expectations in Argentina for competition for Fuchsia magellanica nectar between an invasive bumble bee Bombus terrestris (terr: putative constructor), which often bites holes at the bases of floral tubes to rob nectar, and native B. dahlbomii (dahl: bystander), which normally accesses Fuchsia nectar through the flower mouth (front visits). Robbing holes constitute ENC, as they persist until the 7‐day flowers wilt. The dynamics of the incidence of robbed flowers, abundance of both bees and the number and types of their flower visits (front or robbing) were characterised by alternate‐day surveys of plants during 2.5 months. After initially accessing Fuchsia nectar via front visits, terr switched to robbing and its abundance on Fuchsia increased 20‐fold within 10 days (E2). Correspondingly, the incidence of robbed flowers varied positively with recent and past terr abundance (E1). In contrast, dahl abundance remained low and varied negatively with the incidence of robbed flowers (E3). When terr ceased visiting Fuchsia, dahl abundance increased sixfold within 10 days (E3), possibly because many dahl previously had avoided competition with terr by feeding on other plant species (E4). While terr was present, dahl on Fuchsia used front visits (tolerance) or used existing robbing holes (adoption: E4). The diverse dahl responses suggest partial compensation for competition with terr. ENC alters competitive asymmetry, favouring constructor species. However, bystander responses can partially offset this advantage, perhaps facilitating coexistence.
    Keywords Bombus terrestris ; Fuchsia magellanica ; animal ecology ; asymmetry ; conspecificity ; flowers ; nectar ; niches ; Argentina
    Language English
    Dates of publication 2022-03
    Size p. 580-592.
    Publishing place John Wiley & Sons, Ltd
    Document type Article
    Note JOURNAL ARTICLE
    ZDB-ID 3024-7
    ISSN 1365-2656 ; 0021-8790
    ISSN (online) 1365-2656
    ISSN 0021-8790
    DOI 10.1111/1365-2656.13646
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  7. Article ; Online: Clinal versus disruptive latitudinal variation in fruit traits of a South American mistletoe [Correction: Jan. 2023, 201(1), p. 227-228]

    Amico, Guillermo C. / di Virgilio, Agustina / Schmeda-Hirschmann, Guillermo / Aizen, Marcelo A.

    Oecologia. 2022 Dec., v. 200, no. 3-4, p. 397-411

    2022  , Page(s) 397–411

    Abstract: Fruit traits have historically been interpreted as plant adaptations to their seed dispersers. On the other hand, different environmental factors, which vary spatially and temporally, can shape fruit-trait variation. The mistletoe Tristerix corymbosus ... ...

    Abstract Fruit traits have historically been interpreted as plant adaptations to their seed dispersers. On the other hand, different environmental factors, which vary spatially and temporally, can shape fruit-trait variation. The mistletoe Tristerix corymbosus has a latitudinal distribution along the South American Pacific rim that encompasses two different biomes, the matorral of central Chile and the temperate forest that extends south of the matorral. This mistletoe shows contrasting fruiting phenology (spring vs summer), fruit color (yellow vs green), and seed dispersers (birds vs marsupial) in these two biomes. We characterized geographic variation of morphological and nutritional fruit traits of T. corymbosus to evaluate which macroecological factor, biome or latitude, better explains spatial variation in these variables. For each of 22 populations, we obtained environmental data (temperature, precipitation, and canopy cover), measured fruit and seed morphology traits (size, shape, and weight), and pulp moisture and nutritional content (fiber, protein, fat, carbohydrates, ash, and caloric content). Patterns of variation for each variable were described by fitting and comparing five different simple models varying in slope, intercept or both. Fruit morphology showed a clear biome-related disruptive pattern, seed morphological traits were unrelated to either biome or latitude, whereas nutritional variables showed diverse patterns. Different environmental factors seem to affect fruit development and phenology, determining the observed fruit characteristics, with seed dispersers playing a minor role in shaping these patterns. More generally, the contrasting plant-seed disperser associations we addressed can be interpreted as the outcome of an ecological-fitting rather than of a coevolutionary process.
    Keywords Metatheria ; Santalales ; canopy ; ecosystems ; energy content ; fruit color ; fruit morphology ; fruiting ; fruits ; geographical variation ; latitude ; nutrient content ; phenology ; pulp ; seed morphology ; spring ; summer ; temperate forests ; temperature ; Chile ; Pacific Rim
    Language English
    Dates of publication 2022-12
    Size p. 397-411
    Publishing place Springer Berlin Heidelberg
    Document type Article ; Online
    ZDB-ID 123369-5
    ISSN 1432-1939 ; 0029-8549
    ISSN (online) 1432-1939
    ISSN 0029-8549
    DOI 10.1007/s00442-022-05282-w
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  8. Article: Bumblebee floral neighbors promote nectar robbing in a hummingbird-pollinated plant species in Patagonia

    Gavini, Sabrina S. / Moreno, Emilia / Zamorano-Menay, Francisco / Morales, Carolina L. / Aizen, Marcelo A.

    Arthropod-plant interactions. 2022 Apr., v. 16, no. 2

    2022  

    Abstract: Nectar robbers are common cheaters of plant-pollinator mutualisms by making holes in flower tissues to attain floral rewards often without providing pollination service. Most studies have focused on the consequences of nectar robbing on plant ... ...

    Abstract Nectar robbers are common cheaters of plant-pollinator mutualisms by making holes in flower tissues to attain floral rewards often without providing pollination service. Most studies have focused on the consequences of nectar robbing on plant reproduction, whereas the underlying drivers of spatiotemporal variation in nectar robbing have been comparatively less explored. We assessed variation in nectar robbing of Campsidium valdivianum, an endemic hummingbird-pollinated climber species from the temperate forests of Southern South America, which currently is subjected to nectar robbing by the alien short-tongued Bombus terrestris, and determined if this variation is related to characteristics of the floral neighborhood. We located plants of C. valdivianum and estimated the proportion of flowers with holes. We recorded the presence, identity and distance to the nearest bumblebee-pollinated plants with open flowers. Results showed that the proportion of robbed flowers in C. valdivianum increased almost seven times in the presence of bumblebee flowering plants in the neighborhood. No evidence was found that the proportion of robbed flowers differs between neighborhoods with Berberis darwinii only vs. B. darwinii and Cytisus scoparius, the co-flowering plant species typically visited by bumblebees during the study. Finally, the proportion of robbed flowers increased not only with the presence but also with the proximity of these bumblebee-pollinated plants. Our results suggest that floral neighborhoods attractive to bumblebees can operate as magnets, potentially increasing the intensity of nectar robbing on nearby hummingbird-pollinated species. This study provides novel insights into understanding spatio-temporal variation in nectar robbing.
    Keywords Berberis ; Bombus terrestris ; Cytisus scoparius ; flowers ; nectar ; pollination ; Argentina
    Language English
    Dates of publication 2022-04
    Size p. 183-190.
    Publishing place Springer Netherlands
    Document type Article
    ZDB-ID 2377469-1
    ISSN 1872-8847 ; 1872-8855
    ISSN (online) 1872-8847
    ISSN 1872-8855
    DOI 10.1007/s11829-022-09895-z
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  9. Article ; Online: Behavioural responses by a bumble bee to competition with a niche-constructing congener.

    Rosenberger, Nick M / Aizen, Marcelo A / Dickson, Rachel G / Harder, Lawrence D

    The Journal of animal ecology

    2021  Volume 91, Issue 3, Page(s) 580–592

    Abstract: While feeding, foragers can alter their environment. Such alteration constitutes ecological niche construction (ENC) if it enables future benefits for the constructor and conspecific individuals. The environmental modification may also affect non- ... ...

    Abstract While feeding, foragers can alter their environment. Such alteration constitutes ecological niche construction (ENC) if it enables future benefits for the constructor and conspecific individuals. The environmental modification may also affect non-constructing, bystander species, especially if they share resources with constructor species. If so, ENC could confer the constructor species a competitive advantage by both enhancing its foraging returns and reducing those of bystander species. Expectations - (E1) ENC frequency should vary positively with the recent and current density of the constructor species, and (E2) constructors should use modifications disproportionately. In contrast, bystanders should (E3) experience intensified competition for the affected resource, and (E4) exhibit diverse, possibly mitigating, responses to ENC, depending on opportunity and relative benefits. We investigated these expectations in Argentina for competition for Fuchsia magellanica nectar between an invasive bumble bee Bombus terrestris (terr: putative constructor), which often bites holes at the bases of floral tubes to rob nectar, and native B. dahlbomii (dahl: bystander), which normally accesses Fuchsia nectar through the flower mouth (front visits). Robbing holes constitute ENC, as they persist until the 7-day flowers wilt. The dynamics of the incidence of robbed flowers, abundance of both bees and the number and types of their flower visits (front or robbing) were characterised by alternate-day surveys of plants during 2.5 months. After initially accessing Fuchsia nectar via front visits, terr switched to robbing and its abundance on Fuchsia increased 20-fold within 10 days (E2). Correspondingly, the incidence of robbed flowers varied positively with recent and past terr abundance (E1). In contrast, dahl abundance remained low and varied negatively with the incidence of robbed flowers (E3). When terr ceased visiting Fuchsia, dahl abundance increased sixfold within 10 days (E3), possibly because many dahl previously had avoided competition with terr by feeding on other plant species (E4). While terr was present, dahl on Fuchsia used front visits (tolerance) or used existing robbing holes (adoption: E4). The diverse dahl responses suggest partial compensation for competition with terr. ENC alters competitive asymmetry, favouring constructor species. However, bystander responses can partially offset this advantage, perhaps facilitating coexistence.
    MeSH term(s) Animals ; Argentina ; Bees ; Ecosystem ; Feeding Behavior ; Flowers/physiology ; Plant Nectar ; Pollination/physiology
    Chemical Substances Plant Nectar
    Language English
    Publishing date 2021-12-23
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 3024-7
    ISSN 1365-2656 ; 0021-8790
    ISSN (online) 1365-2656
    ISSN 0021-8790
    DOI 10.1111/1365-2656.13646
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  10. Article ; Online: Pollination success increases with plant diversity in high-Andean communities.

    Gavini, Sabrina S / Sáez, Agustín / Tur, Cristina / Aizen, Marcelo A

    Scientific reports

    2021  Volume 11, Issue 1, Page(s) 22107

    Abstract: Pollinator-mediated plant-plant interactions have traditionally been viewed within the competition paradigm. However, facilitation via pollinator sharing might be the rule rather than the exception in harsh environments. Moreover, plant diversity could ... ...

    Abstract Pollinator-mediated plant-plant interactions have traditionally been viewed within the competition paradigm. However, facilitation via pollinator sharing might be the rule rather than the exception in harsh environments. Moreover, plant diversity could be playing a key role in fostering pollinator-mediated facilitation. Yet, the facilitative effect of plant diversity on pollination remains poorly understood, especially under natural conditions. By examining a total of 9371 stigmas of 88 species from nine high-Andean communities in NW Patagonia, we explored the prevalent sign of the relation between conspecific pollen receipt and heterospecific pollen diversity, and assessed whether the incidence of different outcomes varies with altitude and whether pollen receipt relates to plant diversity. Conspecific pollen receipt increased with heterospecific pollen diversity on stigmas. In all communities, species showed either positive or neutral but never negative relations between the number of heterospecific pollen donor species and conspecific pollen receipt. The incidence of species showing positive relations increased with altitude. Finally, stigmas collected from communities with more co-flowering species had richer heterospecific pollen loads and higher abundance of conspecific pollen grains. Our findings suggest that plant diversity enhances pollination success in high-Andean plant communities. This study emphasizes the importance of plant diversity in fostering indirect plant-plant facilitative interactions in alpine environments, which could promote species coexistence and biodiversity maintenance.
    MeSH term(s) Altitude ; Biodiversity ; Ecosystem ; Flowers/physiology ; Plants ; Pollen/physiology ; Pollination/physiology ; Reproduction/physiology
    Language English
    Publishing date 2021-11-11
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-021-01611-w
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

To top