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Background and Aims: Interactions between species are especially sensitive to environmental changes. The interaction between plants and pollinators is of particular interest given the potential current global decline in pollinators. Reduced pollinator services can be compensated for in some plant species by self-pollination. However, if inbreeding depression is high, selfed progeny could die prior to reaching adulthood, leading to cryptic recruitment failure., Methods: To examine this scenario, pollinator abundance, pollen limitation, selfing rates and inbreeding depression were examined in 12 populations of varying disturbance levels in Sophora microphylla (Fabaceae), an endemic New Zealand tree species., Key Results: High pollen limitation was found in all populations (average of 58 % reduction in seed production, nine populations), together with high selfing rates (61 % of offspring selfed, six populations) and high inbreeding depression (selfed offspring 86 % less fit, six populations). Pollen limitation was associated with lower visitation rates by the two endemic bird pollinators., Conclusions: The results suggest that for these populations, over half of the seeds produced are genetically doomed. This reduction in the fitness of progeny due to reduced pollinator service is probably important to population dynamics of other New Zealand species. More broadly, the results suggest that measures of seed production or seedling densities may be a gross overestimate of the effective offspring production. This could lead to cryptic recruitment failure, i.e. a decline in successful reproduction despite high progeny production. Given the global extent of pollinator declines, cryptic recruitment failure may be widespread., (© The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Inbreeding depression is a central parameter underlying mating system variation in nature and one that can be altered by environmental stress. Although a variety of systems show that inbreeding depression tends to increase under stressful conditions, we have very little understanding across most organisms how the level of inbreeding depression may change as a result of adaptation to stressors. In this work we examined the potential that inbreeding depression varied among lineages of Ipomoea purpurea artificially evolved to exhibit divergent levels of herbicide resistance. We examined inbreeding depression in a variety of fitness‐related traits in both the growth chamber and in the field, and paired this work with an examination of gene expression changes. We found that, while inbreeding depression was present across many of the traits, lineages artificially selected for increased herbicide resistance often showed no evidence of inbreeding depression in the presence of herbicide, and in fact, showed evidence of outbreeding depression in some traits compared to nonselected control lines and lineages selected for increased herbicide susceptibility. Further, at the transcriptome level, the resistant selection lines had differing patterns of gene expression according to breeding type (inbred vs. outcrossed) compared to the control and susceptible selection lines. Our data together indicate that inbreeding depression may be lessened in populations that are adapting to regimes of strong selection. [ABSTRACT FROM AUTHOR]

Human-mediated introductions of predatory mammals to New Zealand have led to massive bird extinctions and population declines. This reduction in bird abundance could have a variety of negative effects on the plants they pollinate, and this has led to recent management efforts to eliminate predatory mammals in some areas. In this study, we utilized variation in management efforts to determine the effects of pollinator service on progeny quantity and quality of an endemic New Zealand tree species, Fuchsia excorticata. Due to its gynodioecious breeding system (separate hermaphroditic and female plants), we were able to estimate effective pollination by scoring pollen deposition on females as a proxy for pollinator service, which we used to examine the effect of pollinator service on both the quantity of fruits produced and the quality of fruits, as measured by the selfing rate of hermaphrodites. We found that increased pollinator service increased progeny quantity, with a stronger effect in females, but had no effect on the quality via selfing rates. The combined effects of pollen limitation and loss of seeds due to inbreeding depression led to hermaphrodites having an estimated 24-80% reduction in the number of offspring reaching reproductive age, even in the highly managed populations. Our results suggest management efforts can have substantial impacts on progeny quantity, but progeny quality is likely influenced by more difficult to manage population or species-specific traits such as tree size, plant sex ratio, and pollinator behavior. [ABSTRACT FROM AUTHOR]