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Este libro pretende aportar información sobre la polinización y la importancia de los polinizadores para los arándanos en Sudamérica, principalmente en Argentina, Brasil y Chile.

Este livro visa fornecer informações sobre a polinização e a importância dos polinizadores para o mirtileiro na América do Sul, principalmente na Argentina, no Brasil e no Chile.

This book aims to provide information on pollination and the importance of pollinators for blueberries in South America, mainly in Argentina, Brazil and Chile.

Calceolaria (Calceolariaceae) is an emblematic and diverse genus in the Americas. Despite being one of the most easily recognized genera in the region and a system with great potential to improve our understanding of different drivers of species diversification in the Andes, its intrageneric evolutionary relationships are still poorly understood. Responding to the need for additional molecular markers to resolve the phylogenetic relationships of the group, we perform plastome analyses and resolve the backbone of the genus. Specifically, using low-coverage genomes for 14 species, we assembled plastomes, estimated and dated phylogenetic hypotheses and evaluated evolutionary trends in the group. Our approach allowed us to resolve the backbone of the genus, identify two main clades and estimate a timing of diversification contemporaneous to major climatic and orogenic events. Our biogeographic reconstructions suggest an independent colonization of the whole range of the genus by both clades. Finally, our evaluations of floral morphology reveal future avenues for investigating the relationship between the pollination biology and diversification of the group.

Invasive species are one of the main biodiversity loss drivers. Some species can establish and thrive in novel habitats, impacting local communities, as is the case of managed pollinators. In this regard, an invasive species' expansion process over time is critical for its control and management. A good example is the European bumblebee Bombus terrestris, which has rapidly invaded the southern part of South America after being repeatedly introduced in Chile for crop pollination since 1997. We assessed the temporal dynamics of B. terrestris invasion in Argentina and Chile by compiling 562 occurrence points from 2000 to 2019. We used two estimators (minimum convex polygon and 95% fixed kernel) to estimate the increase of the invaded area over time. We found that the area invaded by B. terrestris in the southern part of South America presents a linear increase over time, which was consistent for both estimators. In this scenario, species traits, environmental characteristics, and introduction dynamics facilitate a rapid invasion process that will continue to expand, reaching other South American countries in the near future. As this bumblebee is a super-generalist, it probably will expand across South America, as climate niche modelling predicts, if no actions were taken.

In the last decades, pollinators have drastically declined as a consequence of anthropogenic activities that have local and global impacts. The food industry has been expanding intensive agriculture crops, many of them dependent on animal pollination, but simultaneously reducing native pollinator habitats. Chile is a good example of this situation. Chile is becoming an agro-alimentary powerhouse in Latin America, where intensive agriculture expansion is performed at the expense of natural lands, posing a major threat to biodiversity. Here, we discussed the drivers responsible for the decline of pollinators (including habitat loss, pesticides, invasive species, and climate change) and its synergistic effects. This is particularly critical considering that Chile is a hotspot of endemic bee species locally adapted to specific habitats (e.g., Mediterranean-type ecosystems). However, there is a lack of data and monitoring programs that can provide evidence of their conservation status and contribution to crop yields. Based on our analysis, we identified information gaps to be filled and key threats to be addressed to reconcile crop production and biodiversity conservation. Addressing the local context is fundamental to undertake management and conservation actions with global impact.

RESUMEN En esta investigación estimamos la efectividad de polinización en tres poblaciones de Alstroemeria ligtu. Los resultados muestran que Lasia es el género de polinizador más frecuente, cuya efectividad varía entre poblaciones. Proponemos que la efectividad de polinización puede responder a condiciones locales que varían en el rango de distribución de la planta y sus polinizadores.

Bachground: One of the most common evolutionary transitions in angiosperms is the reproductive change from outcrossing to self-fertilization, which has occurred independently in many lineages. This transition has been associated with changes in floral biology, ecology and genetics, with selfing species experiencing reduced floral display and herkogamy, rapid plant growth, and increased inbreeding depression. Here, we aim to test whether self-compatibility was associated with a reduction in floral traits important to the attraction and interaction with pollinators, and a reduction in genetic diversity and inbreeding. Results: Our self-incompatibility tests indicated that 50% of the species studied here are self-incompatible. In relation to floral traits, we found that self-incompatible species do not show a reduction in the size of their floral traits, but rather we found larger corolla, elaiophore area, and herkogamy in self-compatible ones. The microsatellite analysis did not identify any significant decrease in the genetic diversity or increase in inbreeding levels in the self-compatible Calceolaria species. Conclusions: Despite our results go against our expectations, in the case of Calceolaria , their high dependence on only two genera of oil-bees put the species in a vulnerable position, probably facilitating the evolution of mechanisms of reproductive assurance in the absence of pollinators. As a result, the plants maintain their attraction traits while evolving an ability to self. In addition, we also did not detect a significant change in genetic diversity or inbreeding when different reproductive strategies are used. This suggests that selfing could be delayed, facilitating -when possible- the exchange of genes by cross-pollination first, and buffering the negative genetic effects of self-pollination.

Coastal Maulino forest is an endemic forest of central Chile, which has suffered a large history of disturbance, being replaced by large extensions of Pinus radiata plantations. This land transformation conveys high rates of pines invasion into native remnants. In this study we examined to what extent structural features of forest patches explains invisibility of this forest-type. Within eight forest fragments, we sampled 162 plots (10 x 10 m2 each). We quantified seedling pine density and related this estimates with tree cover, litter depth, PAR radiation, and diversity of the resident community. Our results indicate that canopy cover was the most important variable to determine seedling pine density within forest fragments. To preserve the Coastal Maulino forest and the biodiversity containing on it, it seems to be necessary to maintain the native canopy cover. These actions can be highly effective even if we cannot avoid a massive seed arrival from pine plantations which will be unable to regenerate under well conserved native forests.

Tristerix corymbosus (Loranthaceae) is a keystone mistletoe from the South American temperate rainforests. As most mistletoes, T. corymbosus relies on biotic pollination and seed dispersal, which may cause population structure. For a better understanding of its ecology, we isolated and characterized ten polymorphic microsatellite loci for this species. We used 454 Next Generation Sequencing to build a microsatellite library from a high quality DNA sample. We tested 90 sequences from which we obtained ten polymorphic markers. In order to assess their variability, the novel markers were tested in 48 individuals from three locations of the Valdivian Coastal Reserve in Chile. We also estimated genetic differences between pairs of populations using the FST statistic. The mean number of alleles per locus in the 48 individuals studied was 7.1 (2-17 alleles per locus). The observed and expected heterozygosity ranged from 0.298 to 0.634 and from 0.310 to 0.881, respectively. There were genetic differences among the three populations assessed, according to the FST values (ranging from 0.048 to 0.100, all significant) and, the number of alleles per locus ranged from 3.9 to 5.1. These are the first microsatellite markers developed for T. corymbosus, and they arise as a powerful tool for studying population structure, genetic diversity and gene flow at the landscape scale, along its distribution.

Pollinator species are widely accepted as an important factor in plant reproductive isolation. Although mostly investigated in plants visited by different groups of pollinators (e.g., hummingbirds vs bees), few studies have examined the role of pollinators belonging to the same taxonomic group (e.g., only bees) on plant reproductive isolation. In this study, we investigate this question by evaluating pre- and post-zygotic mechanisms putatively involved in the reproductive isolation of two oil-rewarding sympatric Calceolaria species (i.e., Calceolaria filicaulis and C. arachnoidea) in an Andean ecosystem of Chile. We estimated reproductive isolation values using a combination of field (pollinator visitation rates) and experimental (intra and interspecific manual cross-pollination and seed germination of parents and hybrids) evidence. The two Calceolaria species were preferentially visited by different oil-collecting bee species. Results from hand cross-pollination experiments indicate that intraspecific crossings produced significantly more seeds than interspecific ones. Notwithstanding, seed germination essays did not reveal differences between parental and hybrids. Taken together, these results suggest that pollinator species are responsible for most of the reproductive isolation in the two Calceolaria species studied here. This study is the first assessment of pollinator-mediated reproductive isolation in Calceolaria species and the first to document reproductive barriers in oil-rewarding plants.

Plant-animal interactions are a key component for biodiversity maintenance, but they are currently threatened by human activities. Habitat fragmentation might alter ecological interactions due to demographic changes, spatial discontinuities, and edge effects. Also, there are less evident effects of habitat fragmentation that potentially alter selective forces and compromise the fitness of the interacting species. Changes in the mutualistic and antagonistic interactions in fragmented habitats could significantly influence the plant reproductive output and the fauna assemblage associated with. Fragmented habitats may trigger contemporary evolution processes and open new evolutionary opportunities. Interacting parties with a diffuse and asymmetric relationship are less susceptible to local extinction but more prone to evolve towards new interactions or autonomy. However, highly specialized mutualisms are likely to disappear. On the other hand, ecological interactions may mutually modulate their response in fragmented habitats, especially when antagonistic interactions disrupt mutualistic ones. Ecoevolutionary issues of habitat fragmentation have been little explored, but the empiric evidence available suggests that the complex modification of ecological interactions in fragmented habitats might lead to nonanalogous communities on the long term.

Herbivory has been long considered an important component of plant-animal interactions that influences the success of invasive species in novel habitats. One of the most important hypotheses linking herbivory and invasion processes is the enemy-release hypothesis, in which exotic plants are hypothesized to suffer less herbivory and fitness-costs in their novel ranges as they leave behind their enemies in the original range. Most evidence, however, comes from studies on leaf herbivory, and the importance of flower herbivory for the invasion process remains largely unknown. Here we present the results of a meta-analysis of the impact of flower herbivory on plant reproductive success, using as moderators the type of damage caused by floral herbivores and the residence status of the plant species. We found 51 papers that fulfilled our criteria. We also included 60 records from unpublished data of the laboratory, gathering a total of 143 case studies. The effects of florivory and nectar robbing were both negative on plant fitness. The methodology employed in studies of flower herbivory influenced substantially the outcome of flower damage. Experiments using natural herbivory imposed a higher fitness cost than simulated herbivory, such as clipping and petal removal, indicating that studies using artificial herbivory as surrogates of natural herbivory underestimate the real fitness impact of flower herbivory. Although the fitness cost of floral herbivory was high both in native and exotic plant species, floral herbivores had a three-fold stronger fitness impact on exotic than native plants, contravening a critical element of the enemy-release hypothesis. Our results suggest a critical but largely unrecognized role of floral herbivores in preventing the spread of introduced species into newly colonized areas.

La fragmentacion del habitat puede afectar el diseno morfologico de los insectos voladores de distintas maneras, a traves de cambios en los costos y beneficios de los patrones de dispersion. Como resultado, es probable que alas mas grandes puedan ser favorecidas cuando los recursos necesarios se encuentren dispersos a lo largo del paisaje fragmentado. En esta investigacion se puso a prueba esta prediccion en Bombus dahlbomii (Guerin), un polinizador nativo de Chile asociado al bosque Maulino fragmentado. Mediante trampas colgantes, se capturaron individuos en el bosque nativo continuo, en cuatro pequenos fragmentos y en dos plantaciones de Pinus radiata (matriz). A cada individuo colectado se le midio su tamano corporal (mm) y el largo de su primer y segundo par de alas (mm). En total, fueron capturados 280 individuos. El tamano corporal y el largo de ambos pares de alas fue mayor en los fragmentos y en la matriz, en comparacion con el bosque continuo. Ademas, se observo una relacion positiva y significativa entre la longitud de las alas y el tamano corporal en todos los habitats, sin embargo, la varianza explicada fue menor en el bosque continuo que en los fragmentos y la matriz. Estos resultados sugieren que la fragmentacion del bosque Maulino podria favorecer fenotipos con alas mas grandes, probablemente con mayores capacidades de vuelo para la busqueda de recursos escasos durante el forrajeo.

Pollinator-mediated selection is one of the most important factors driving adaptation in flowering plants. However, as ecological conditions change through habitat loss and fragmentation, the interactions among species may evolve in new and unexpected directions. Human-induced environmental variation is likely to affect selection regimes, but as yet no empirical examples have been reported. In the study reported here, we examined the influence of human-induced habitat transformation on the composition of pollinator assemblages and, hence, pollinator-mediated selection on the flower phenotype of Viola portalesia (Violaceae). Our results indicate that pollinator assemblages differed substantially in terms of species composition and visitation rate between nearby native and transformed habitats. Similarly, the insect species that contributed most to visitation rates differed between plant populations. While the magnitude and sign of pollinator-mediated selection on flower length and width did not differ between sites, selection for flower number lost significance in the transformed habitat, and a significant pattern of disruptive selection for flower shape, undetected in the native habitat, was present in the transformed one. Overall, the results of this study suggest that human-induced habitat change may not only modify the species composition of pollinator assemblages, relaxing the selection process on some flower characters, but they may also create new opportunities for fitness-trait covariation not present in pristine conditions.

FindingsPlant-pollinator interactions have been seen as a co-adaptative process between pollinators and flowers (Johnsonand Steiner 2000). Even though specialized pollinatorsystems do exist, most plants are pollinated by a widespectrum of pollinators (Ollerton 1996; Waser et al. 1996).Accordantly, the degree of generalization in a plant-pollinator system may vary temporally and spatially in rela-tion to biotic or abiotic environment fluctuations (seeGomez and Perfectti 2009, for review). In general, spatialvariation has been invoked as the most important factor inthe maintenance of generalization (Herrera 1996; Fensteret al. 2004), and temporal variation has been underlooked(but see Williams et al. 2001; Gomez 2002). In the longrun, pollinator variation can be translated into inter-population variation in the degree of generalization, whichsubsequently can affect the reproductive success of plantspecies (Suarez et al. 2009; Botto-Mahan et al. 2011).Alstroemeria ligtu var. simsii Sprengel (Alstroemeriaceae)is a perennial herb endemic to central Chile (Munoz andMoreira 2003). A. ligtu simsii is a hermaphroditic self-incompatible subspecies that relies entirely on pollinatorsfor reproduction (Arroyo and Uslar 1993). The zygo-morphic flowers are 4 to 6 cm long and arranged in um-bels with one to four flowers each. The flowers consistof four red tepals, two distinctive yellow tepals streakedwith brownish lines (Figure 1A). The flowering seasonextends from November to January, following by thefruiting season that ends in February (Arroyo and Uslar1993; Botto-Mahan et al. 2011).The study was carried out during two austral spring sea-sons (2011 and 2012), in six populations that comprisemost of the distributional range of A. ligtu simsii fromcentral Chile (Figure 1B). The region is characterized by aMediterranean-type climate (di Castri and Hajek 1976),where populations were exposed to similar variation oftemperature and precipitation (considering maximum andminimum of both abiotic variables in the warmest,coldest, wettest, and driest months), which did not dif-fer significantly among them (temperature: F

71°00′ W) in the Region del Maule, Chile. The sample site is located in the Reserve at 2,200 m a.s.l. and has a Mediterranean-type climate, with most rainfall concentrated in the winter season (di Castri and Hajek 1976). In the study site, C. filicaulis and C. arachnoidea inhabit in sympatry and are distributed in monospecific patches, surrounded by a vegetation matrix that includes Mimulus luteus Linnaeus (Schrophulareaceae), Mimulus cupreus Dombrain (Schrophulareaceae), Hypochoeris acaulis Britton (Asteraceae), Pozoa coriacea Lagasca & Segura (Apiaceae), and Azorella incisa Weddell (Apiaceae). To determine the breeding system of Calceolaria species, a pollination-controlled experiment was conducted in 120 buds per species. Buds were bagged with a mesh, and each of the following treatments were randomly assigned: (1) control (C), intact flowers exposed to natural pollination; (2) hand cross-pollination (HC), emasculated flowers pollinated with pollen from another plant situated at least 1 m apart; (3) automatic pollination (AP), bagged buds without manipulation; and (4) hand self-pollination (HS), emasculated flowers pollinated by its own pollen. Pollination success was estimated as seed set per plant, and self-incompatibility (ISI) and autogamy (IAS) indexes (Arroyo and Uslar 1993) were estimated as

Floral integration may result from the combined effects of pollinator-mediated selection, genetic correlations and abiotic factors. Thus, by sampling a set of populations in the field and examining their variation of floral correlations in relation to pollinators and abiotic factors, we intended to shed light on the ecological factors underlying the evolution of floral integration. In this study, floral integration patterns and the composition of pollinator assemblage were characterized across ten populations of Alstroemeria ligtu to test the following: (1) Whether the patterns of floral integration estimated at population level covary with the composition of local pollinator assemblage, climate and/or geographic distance. (2) Whether the magnitude of floral integration decreases with the number or the morphological variability of pollinators. (3) Whether the behavior of the three most widespread pollinators is affected by floral integration. Our results indicated that populations with similar patterns of integration showed greater similitude in pollinator assemblages, but that this was not related to climate or geographic distance. We also found that the most widespread pollinator, Centris nigerrima, invested lower handling time in populations with higher levels of floral integration. The magnitude of floral integration was not related to taxonomical diversity, yet, unexpectedly, correlated positively with the variability of pollinator proboscis length. We suggest that variation in the magnitude and pattern of floral integration across the species range was related to the composition of pollinator assemblage, and not to pollinator diversity per se, nor to climatic variables. A. ligtu was visited by numerous pollinators, but floral integration patterns are likely shaped by only a subset of them, such as C. nigerrima, which is sensitive to variations in floral architecture.

Nectar robbing may have an indirect negative effect on plant reproduction by discouraging legitimate pollinator species from visiting robbed flowers. In this study, we set up a 2 × 2 factorial design with nectar-robbing ants and hummingbird pollination to test for non-additive effects on fruit set, seed mass, and seed germination of the leafless mistletoe Tristerix aphyllus (Loranthaceae). Even though ants caused conspicuous damage at the base of the floral tubes, nectar availability was reduced by only 8 % in the presence of ants. The green-backed firecrown Sephanoides sephaniodes was insensitive to the presence of ants. Rather, the bird responded to flower number and the presence or the absence of damage, but not to the extent of damage within inflorescences. As hummingbirds were largely insensitive to variation in nectar robbing, the interaction ant × hummingbird had no effect on plant-reproductive success. Thus, the factorial experiment did not provide evidence for indirect negative effects of nectar robbing on plant reproduction. These results suggest that indirect effects of nectar robbers on pollinator behaviour may occur under a more restricted set of conditions than those previously considered. We suggest that the low amount of nectar removed by nectar-robbing ants was insufficient for hummingbirds to avoid robbed flowers, which restricted the potential for non-additive effects.

El impacto indirecto de la herbivoria floral sobre la reproduccion de las plantas puede depender del ambiente de polinizacion, particularmente de la presencia o ausencia de especies de polinizadores con capacidad de discriminar entre las flores danadas y no danadas. El cambio en el ensamble de polinizadores, debido a la modificacion del habitat, puede alterar el impacto de la herbivoria floral sobre el exito reproductivo de las plantas. En este trabajo, se evaluo el efecto de la herbivoria floral sobre la produccion de semillas de Viola portalesia (Gay) en dos ambientes contrastantes, un habitat nativo, con bajos niveles de perturbacion y otro habitat altamente intervenido por plantaciones de Pinus radiata. Aun cuando los dos habitats difirieron substancialmente en la composicion del ensamble de polinizadores y tasas de visitas, el dano floral realizado sobre los diferentes petalos no tuvo efectos sobre la produccion de semillas ni dentro ni entre habitats, indicando que el cambio en el ensamble de polinizadores no tiene impacto reproductivo a traves de la discriminacion de flores danadas. Se observo, sin embargo, un fuerte efecto del habitat sobre la produccion de semillas siendo esta mayor en la plantacion de pino que en el habitat nativo. La produccion de semillas por flor relativa al numero de flores aumento a una mayor tasa en la plantacion de pino, lo cual sugiere una respuesta numerica de los polinizadores a cambios en la disponibilidad de alimento en este habitat.