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Reproductive allocation and cost play a crucial role in the survival of organisms, but research on these traits in bryophytes has been limited and inconsistent. To address this, we conducted a literature review focusing on bryophyte studies. Our goal was to clarify inconsistencies and explore reproductive allocation and cost concepts, as well as current trends in bryophyte reproduction. We examined different approaches and highlighted advantages and limitations. We emphasized five key topics: the importance of understanding reproductive allocation and reproductive cost in bryophytes; the significance of bryophytes as model organisms; historical research; terminological and methodological inconsistencies; sexual dimorphism and reproductive allocation; and measurement methods. Furthermore, we provided insights into future perspectives. Based on our findings, we advocate for standardized quantification of reproductive allocation. Standardization would enhance comparability and synthesis of results, ultimately advancing our understanding of reproductive allocation and cost of reproduction in bryophytes. Keywords Biomass Allocation * Liverworts * Moss * Reproductive Effort * Reproductive Investment * Trade-off, Introduction Life history theory, an approach that investigates the timing of key events in an organism's life cycle, predicts that every resource produced by an organism is allocated to its [...]

Asteraceae are among the most abundant angiosperm families on oceanic islands. The reproductive biology of Asteraceae is reviewed and the attributes of the family contributing to their success on islands are discussed. Asteraceae are effective dispersers (the small, single-seeded fruits are moved great distances by wind and birds), and colonization is most likely limited by establishment. The pollinators of the colonizing ancestors rarely disperse with them to islands. Divorced from the pollinators of their ancestral habitats, the capitulum of aggregated small, shallow flowers typical of Asteraceae facilitates pollination of colonizers by various novel biotic visitors and by wind. Self-compatible (SC) colonizing ancestors are common, permitting establishment of sexual populations from one or few propagules. However, several large insular lineages of Asteraceae originated from functionally self-incompatible (SI) colonizers that may have also possessed the capacity to set some self-seed. Establishment may also be facilitated by dominance relationships among S-alleles in the sporophytic SI (SSI) system of Asteraceae, increasing cross-compatibility within small populations. Factors potentially promoting outcrossing in SC Asteraceae are: gynomonoecy, with temporal separation of receptive pistillate ray florets and pollen presentation in the hermaphroditic disc florets of a capitulum (interfloral protogyny); and intrafloral protandry where pollen presentation occurs before stigmata become receptive. Dioecy, gynodioecy, and monoecy are infrequent sexual systems in insular Asteraceae. Multiple paternity is similar in island composites to other Asteraceae, suggesting that neither compatible mates nor pollinators are typically limiting. Additional studies, particularly with genomic markers, are needed for more refined insights into mating systems and paternity in island Asteraceae as these results have important conservation implications. Keywords Asteraceae * Conservation biology * Oceanic islands * Reproductive biology, Introduction Flowering plants face multiple challenges in dispersal, establishment, and diversification in oceanic archipelagos (Baker, 1955; Carlquist, 1974, chapts. 1,2, 3, 11, 13; Pannell, 2015; Pannell et al., 2015). Despite [...]

The significance of maternal and progeny environment to chasmogamy (CH) and cleistogamy (CL) in perennial plants is not well known. The perennial grass Danthonia compressa produces CH spikelets capable of outcrossing on terminal panicles in summer followed by selling axillary CL spikelets in autumn. This study compared CH and CL seed mass, germination, seedling size, tillering, and reproduction in a sunny woodland edge and shaded interior habitat in the Catskill Mountains of New York State. CL seeds were significantly heavier than CH seeds. Numbers and mass of both seed types were greater in the edge. CL seeds showed much greater germination than CH seeds in both environments during spring, 2018; CL seedlings were larger than CH seedlings in the sunnier habitat. Survival was much greater in the edge than interior and higher for CL seedlings. After 27 months, maternal effects were mostly not detected and there was no significant effect of plant type (CH vs CL) on tiller production, final biomass, or reproduction via CH and CL. For this native grass, non-dispersed CL seeds may be more critical to seedling establishment and population persistence due to greater mass and germinability, and better plant survival, relative to smaller, dispersible CH seeds. Key words: Cleistogamy, light, maternal effects, mixed mating system, perennial grass, Poaceae, Introduction Cleistogamy (CL) is the production of closed, self-fertilizing flowers and occurs in almost 700 angiosperm species distributed among 50 plant families (Culley and Klooster 2007). Early descriptions of CL [...]

The reproductive ecology of the semi-serotinous species black spruce (Picea mariana (Mill.) BSP) in northern boreal forests remains poorly understood. There is a general lack of data on cone/seed production and viability as a function of biotic treelevel characteristics and abiotic variables. No studies currently exist to quantify these differences over a large gradient in temperature, elevation, and precipitation. Extensive physical, ecological, dendrometric, and reproductive data were collected from young to very old black spruce stands in northern Quebec. ANOVA and general linear mixed models were used to examine interannual cone production, and the relative importance of the biotic and abiotic explanatory factors in determining total cone production; length of the cone-bearing zone; filled seeds per cone; proportion of filled seeds; and seed viability. The results illustrate that the reproductive ecology of black spruce in northern cold forests is mainly explained by biotic variables such as age and diameter [DELTA]T breast height, and by abiotic variables related to temperature such as elevation, length of the growing season, and growing degree-days. Black spruce exhibits a lower reproductive potential in northern cold forests, making it possibly less resilient to increased fire frequency, particularly in unproductive and very young or very old stands. Key words: black spruce, reproductive ecology, cone production, seed production, germination, boreal forest, forest fire, seed viability, resilience, adaptation L'ecologie de la reproduction de l'espece semi-serotineuse, l'epinette noire (Picea mariana (Mill.) BSP) dans les forets boreales froides est encore peu documentee. Il existe un manque general de donnees sur la production des cones/graines et leur viabilite en fonction des caracteristiques biotiques au niveau de l'arbre et des variables abiotiques. Aucune etude n'existe actuellement pour quantifier ces differences sur un large gradient de temperature, d'altitude, et de precipitations. De nombreuses donnees physiques, ecologiques, dendrometriques et reproductives ont ete recueillies dans des peuplements d'epinette noire jeunes a tres ages dans le nord du Quebec. Des ANOVA et des modeles mixtes lineaires generaux ont ete utilises pour examiner la production annuelle de cones et l'importance relative des facteurs explicatifs biotiques et abiotiques dans la determination de la production totale de cones; la longueur de la cime comportant des cones; le nombre de graines pleines par cone; la proportion de graines pleines; et leur taux de germination. Les resultats indiquent que l'ecologie de la reproduction de l'epinette noire dans les forets boreales nordiques est expliquee par des variables biotiques telles que l'age et le DHP, et des variables abiotiques liees a la somme thermique regionale telles que l'altitude, la duree de la saison de croissance, et les degres-jours de croissance. L'epinette noire presente un potentiel reproductif plus faible dans les forets froides du nord, ce qui la rend moins resistante a l'augmentation de la frequence des feux, particulierement dans les peuplements improductifs et tres jeunes ou tres vieux. Mots-cles : epinette noire, ecologie de la reproduction, production des cones, production des graines, germination, foret boreale, feu de foret, taux de germination, resilience, adaptation, 1. Introduction Black spruce (Picea mariana (Mill.)) is one of the most common and commercially important conifer species in the boreal forest of eastern North America (Viereck and Johnston 1990), [...]

Sub-Antarctic giant kelp (Macrocystis pyrifera) forests have remained relatively wild and far from anthropogenic pressures. However, they are increasingly exposed to multiple stressors that might affect kelp forest persistence. The urban impact of a coastal city, Ushuaia (54° S 68° W), in the Beagle Channel, Argentina, on giant kelp forest environments was evaluated in this study and implications on morphological variability were explored. Seasonal samplings were conducted from 2019 to 2021 in two contrasting sites: an urban site directly exposed to coastal discharges, and a non-urban site. Our results indicate that the combination of coastal discharges, kelp canopy and low wave exposure increases light attenuation inside kelp forests, promoting coastal darkening. Additionally, and based on the present results, we present the first record of algal turf in the Beagle Channel. We further propose the Kelp Structure Index to describe the effect of environmental conditions on kelp structure, which highlights an increased blade surface in sites with urban impacts. These results suggest that giant kelp shows high plasticity in morphological traits under varying environmental conditions, particularly in environments exposed to coastal darkening effects. However, the presence of turf indicates that urban pressures might be severely limiting kelp forest health., Author(s): Julieta Kaminsky [sup.1] , María Bagur [sup.1] , Irene Ruth Schloss [sup.1] [sup.2] [sup.3] , Soledad Diodato [sup.1] [sup.2] , Mariano Rodríguez [sup.2] , Alejandro H. Buschmann [sup.4] , [...]

Heliotropism of flowers is thought to provide a reproductive advantage to individuals of many species; yet, there are few clear demonstrations of a fitness advantage provided by heliotropism, most of which are almost completely restricted to plants from the arctic or alpine regions where a heat gain provides an advantage to the plants. In this study, we report heliotropism in the white trillium, an early spring blooming species from the temperate forests of eastern North America. The white trillium shows horizontal seasonal heliotropism with flowers mainly facing south throughout the summer, but it also exhibits daily horizontal and vertical heliotropism with the orientation of the flower tracking the sun during the day. The study of 479 tethered plants indicated that seasonal heliotropism provides a reproductive advantage to the white trillium, with south-facing individuals showing a 12% increase in fertilized ovules compared to north-facing plants. The ecology of this long-lived perennial is, in many aspects, similar to that of alpine and arctic heliotropic species. Indeed, white trilliums are insect-pollinated and they flower when the weather is cold, before the trees leaf out. This suggests that there are potentially more species for which heliotropism is advantageous amongst early spring flowers from the temperate forest. Key words: heliotropism, white trillium, fertilized ovules, fitness, plant reproduction On pense que l'heliotropisme des fleurs procure un avantage reproductif aux individus de nombreuses especes. Pourtant, il existe peu de demonstrations claires de l'avantage de 1'heliotropisme sur le plan de la valeur adaptative, et ces demonstrations sont presque toutes limitees aux plantes des regions arctiques ou alpines, ou un gain de chaleur procure un avantage aux plantes. Dans cette etude, nous decrivons 1'heliotropisme chez le trille blanc, une espece a floraison printaniere precoce des forets temperees de Test de l'Amerique du Nord. Le trille blanc montre un heliotropisme saisonnier horizontal avec des fleurs principalement orientees vers le sud tout au long de l'ete, mais il presente egalement un heliotropisme horizontal et vertical quotidien avec l'orientation de la fleur suivant le soleil pendant la journee. L'etude de 479 plantes attachees a indique que 1'heliotropisme saisonnier procure un avantage reproductif au trille blanc, les individus orientes vers le sud presentant une augmentation de 12 % d'ovules fecondes par rapport aux plantes orientees vers le nord. L'ecologie de cette plante vivace a longue duree de vie est, sous de nombreux aspects, similaire a celle des especes heliotropes alpines et arctiques. En effet, les trilles blancs sont pollinises par les insectes et ils fleurissent lorsque le temps est froid, avant l'apparition du feuillage des arbres. Cela suggere qu'il y a potentiellement plus d'especes pour lesquelles 1'heliotropisme est avantageux parmi les fleurs printanieres precoces de la foret temperee. [Traduit par la Redaction] Mots-cles : heliotropisme, trille blanc, ovules fecondes, valeur adaptative, reproduction vegetale, Introduction The heliotropism of flowers has attracted curiosity and interest amongst evolutionary ecologists for more than 50 years (Hocking and Sharplin 1965; Hocking 1968; Kevan 1972, 1975). Heliotropism is the [...]

Abstract Apomixis is considered to be a natural mode of clonal propogation from seed to seed, in which progeny serves as a replica of maternal genotype. The process evades creation [...]

Phenology is an ecologically critical attribute that is commonly coordinated with other plant traits. Phenological shifts may be the result of evolutionary adjustments to persistently new conditions, or they may be transitory, varying with annual fluxes in abiotic conditions. In summer-dry, fire-prone Mediterranean-type climates, for example, many plant lineages have historically migrated from forests to more arid shrublands resulting in adaptive trait changes. These shifts in habitat abiotic conditions and biotic interactions influence morphology of flowers and fruits and interact with phenological timing. The Arbutoideae (Ericaceae) is one lineage that illustrates such modifications, with fruit characters evolving among genera from fleshy to dry fruit, thin to stony endocarps, and bird to rodent dispersal, among other changes. We scored herbarium collections and used ancestral trait analyses to determine phenological shifts among the five Arbutoid genera found in semi-arid climates. Our objective was to determine if phenology shifts with the phylogenetic transition to different reproductive characters. Our results indicate that phenological shifts began with some traits, like the development of a stony endocarp or dry fruits, but not with all significant trait changes. We conclude that early phenological shifts correlating with some reproductive traits were permissive for the transition to other later character changes. Key words: Ericaceae, fire regime, obligate seeding, scatter-hoarding, seed predation. La phenologie est un attribut critique d'un point de vue ecologique qui est generalement coordonne avec d'autres traits des vegetaux. Les changements phenologiques peuvent etre le resultat d'ajustements evolutifs a de nouvelles conditions persistantes, ou transitoires, qui varient avec le flux annuel des conditions abiotiques. Dans les climats mediterraneens secs en ete et sujets aux incendies, par exemple, de nombreux lignages de vegetaux ont historiquement migre des forets vers des zones arbustives plus arides, entrainant des changements en matiere de traits adaptatifs. Ces changements dans les conditions abiotiques de l'habitat et les interactions biotiques influencent la morphologie des fleurs et des fruits et interagiront avec le calendrier phenologique. Les Arbutoideae (Ericaceae) constituent un lignage qui illustre de telles modifications, les caracteres des fruits evoluant parmi les genres, de fruits charnus a secs, d'endocarpes minces a pierreux, et de dispersion par les oiseaux a une dispersion par les rongeurs, entre autres changements. Les auteurs ont analyse des collections d'herbiers et utilise l'analyse de traits ancestraux pour caracteriser les changements phenologiques parmi les cinq genres d'Arbutoides trouves dans des climats semi-arides. Leur objectif consistait a determiner si la phenologie change avec la transition phylogenetique vers des caracteres reproducteurs differents. Leurs resultats indiquent que les changements phenologiques ont commence avec certains traits, comme le developpement d'un endocarpe pierreux ou de fruits secs, mais pas avec tous les changements de traits significatifs. Ils concluent que les changements phenologiques precoces en correlation avec certains caracteres reproducteurs etaient permissifs pour la transition vers d'autres changements de caracteres ulterieurs. [Traduit par la Redaction] Mots-cles : Ericaceae, regime des incendies, semis obligatoire, eparpillement, predation des graines., Introduction Phenological changes that occur in coordination with fruit types is an understudied dimension of fruit evolution compared with dispersal or other traits (Forrest and Miller-Rushing 2010). Most studies investigating [...]