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Background and Aims Androdioecy, the co-occurrence of males and hermaphrodites, is a rare reproductive system. Males can be maintained if they benefit from a higher male fitness than hermaphrodites, referred to as male advantage. Male advantage can emerge from increased fertility owing to resource reallocation. However, empirical studies usually compare sexual phenotypes over a single flowering season, thus ignoring potential cumulative effects over successive seasons in perennials. In this study, we quantify various components of male fertility advantage, both within and between seasons, in the long-lived perennial shrub Phillyrea angustifolia (Oleaceae). Although, owing to a peculiar diallelic self-incompatibility system and female sterility mutation strictly associated with a breakdown of incompatibility, males do not need fertility advantage to persist in this species, this advantage remains an important determinant of their equilibrium frequency. Methods A survey of >1000 full-sib plants allowed us to compare males and hermaphrodites for several components of male fertility. Individuals were characterized for proxies of pollen production and vegetative growth. By analysing maternal progeny, we compared the siring success of males and hermaphrodites. Finally, using a multistate capture–recapture model we assessed, for each sexual morph, how the intensity of flowering in one year impacts next-year growth and reproduction. Key Results Males benefitted from a greater vegetative growth and flowering intensity. Within one season, males sired twice as many seeds as equidistant, compatible hermaphroditic competitors. In addition, males more often maintained intense flowering over successive years. Finally, investment in male reproductive function appeared to differ between the two incompatibility groups of hermaphrodites. Conclusion Males, by sparing the cost of female reproduction, have a higher flowering frequency and vegetative growth, both of which contribute to male advantage over an individual lifetime. This suggests that studies analysing sexual phenotypes during only single reproductive periods are likely to provide inadequate estimates of male advantage in perennials. [ABSTRACT FROM AUTHOR]

Background: Two widely cultivated annual buckwheat crops, Fagopyrum esculentum and F. tataricum, differ from each other in both rutin concentration and reproductive system. However, the underlying genetic mechanisms remain poorly elucidated. Results: Here, we report the first haplotype-resolved chromosome-level genome assemblies of the two species. Two haplotype genomes of F. esculentum were assembled as 1.23 and 1.19 Gb with N50 = 9.8 and 12.4 Mb, respectively; the two haplotype genomes of F. tataricum were 453.7 and 446.2 Mb with N50 = 50 and 30 Mb, respectively. We further annotated protein-coding genes of each haplotype genome based on available gene sets and 48 newly sequenced transcriptomes. We found that more repetitive sequences, especially expansion of long terminal repeat retrotransposons (LTR-RTs), contributed to the large genome size of F. esculentum. Based on the well-annotated sequences, gene expressions, and luciferase experiments, we identified the sequence mutations of the promoter regions of two key genes that are likely to have greatly contributed to the high rutin concentration and selfing reproduction in F. tartaricum. Conclusions: Our results highlight the importance of high-quality genomes to identify genetic mutations underlying phenotypic differences between closely related species. F. tataricum may have been experienced stronger selection than F. esculentum through choosing these two non-coding alleles for the desired cultivation traits. These findings further suggest that genetic manipulation of the non-coding promoter regions could be widely employed for breeding buckwheat and other crops. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthetic amorphous silica is the authorized food additive Silicon dioxide or E551. • A 90-day oral toxicity study was performed at dose levels close to human exposure through E551. • Male reproductive system is not target showing no histophatological or genotoxic effects. • In female no histophatological/genotoxic effects in ovary and limited effects in uterus. • The study identified a limited concern only for female reproductive health. Synthetic amorphous silica (SAS) consists of agglomerates and aggregates of primary particles in the nanorange (<100 nm) and it is the E551 authorized food additive. The potential risks for human health associated to dietary exposure to SAS are not completely assessed; in particular, data on male and female reproductive systems are lacking. A 90-day oral toxicity study with pyrogenic SAS nanomaterial NM-203 was carried out on the basis of the OECD test guideline 408 in the frame of the NANoREG project. Adult Sprague-Dawley rats of both sexes were orally treated for 90 days with 0, 2, 5, 10, 20 and 50 mg SAS/kg bw per day. Dose levels were selected to be as close as possible to the expected human exposure to food additive E551. The present paper provides specific information on potential effects on male and female reproductive systems, through the evaluation of serum biomarkers, sperm count, histopathological analysis of testis, epididymis, ovary and uterus and real-time PCR on uterus; potential genotoxic alterations were evaluated by comet assay on testis, sperm and ovary. NM-203 did not induce histophatological and genotoxic effects in male reproductive system. In female rats, ovary is not target of NM-203 and only tissue-specific effects on uterus were recorded up to 10 mg/kg bw per day. To our best knowledge, this is the first study providing data on male and female reproductive systems after long-term, repeated oral exposure at dose levels close to dietary human exposure, which identifies a limited concern only for female reproductive health. [ABSTRACT FROM AUTHOR]

Island plants provide special opportunities for the study of evolution and ecology. In field and greenhouse studies we characterized a model reproductive system for Plocama pendula , endemic to the Canary Islands. This species has a complicated and not immediately obvious reproductive system. Pollination is biotic, and all flowers are morphologically hermaphroditic, but half of the plants characteristically bear flowers with nectar, pistils with reflexed stigmatic lobes and pollen-less anthers (i.e. they are functionally female flowers). The other half bear nectar-less flowers with abundant pollen and full-sized pistils that mostly have un-reflexed stigmatic lobes (i.e. they are hermaphroditic flowers functioning mostly as males). However, experiments show these pollen-bearing flowers to be self-compatible. Thus, the functionally male flowers have a breeding system that allows selfing in limited circumstances, but the functionally male flowers produce far fewer fruits than do functionally female flowers. With morphologically gynodioecious, functionally largely dioecious flowers, sometimes capable of selfing, the reproductive system of this species could be labelled as 'leaky' in many respects. Thus, we propose that P. pendula has colonized new habitats and persists in substantial populations at least in part because it manifests a reproductive system that is a model for successfully balancing the often-conflicting evolutionary demands of colonization, establishment and persistence. [ABSTRACT FROM AUTHOR]

This study aims to evaluate a reproductive systems augmented reality (AR) application for use in sexual health education. AR material included learner interactivity and a 3D video. Sixteen counselor candidates voluntarily registered to the sexual health class. A Reproductive Systems Questionnaire and an AR interview form were used to collect data. The participants were evaluated with a pretest, post-test and retention test. A significant improvement from pretest to post-test indicated that the AR application enhanced participants' knowledge of reproductive organs and their positions. Participants learned more about female reproductive systems than male reproductive systems. [ABSTRACT FROM AUTHOR]

Reproductive systems are life attributes important in defining the demography and genetic constitution of invasive alien species populations. We describe the phenology, floral behavior and floral visitors in Mexican populations of Leonotis nepetifolia considered invasive in America, Asia and Oceania. The mating system was determined through pollination experiments and, with a morphological analysis of flowers (outcrossing index, OCI) and pollen/ovule ratio, the breeding system was evaluated. Germination of 1 and 2‐year‐old seeds was tested to assess the potential characteristics of germination. Leonotis nepetifolia was reproductive for 7 months (June to December) and tended towards a specific season during autumn. Anthesis lasted 36 hr with protogyny and no hercogamy, with floral visitors of Apodiformes, Hymenoptera, Lepidoptera and Thysanoptera. Pollination experiments indicated a mixed mating system, whereas the OCI and the pollen/ovule ratio pointed towards a facultative xenogamous breeding system. Seed production was high (1,445 ± 132 seeds/plant); the seeds had potential longevity and were neutral photoblastic. One‐year‐old seeds germinated slightly later (x¯ = 2.6 ± 0.11 days) than 2‐year‐old seeds (x¯ = 1.9 ± 0.02 days), both synchronously (IS1yr = 0.88 ± 0.03 and IS2yr = 0.82 ± 0.02). Germination percentage for 1‐year‐old seeds was lower (55.33 ± 4.40%) than that of 2‐year‐old seeds (94.18 ± 0.59%), suggesting a potential longevity of the seeds in an optimal environment. Reproductive characteristics, such as wide reproductive period, mixed breeding system, copious seed production, seeds with potential longevity, and quick and synchronic germination in different light conditions, favor the invasive capacity of Leonotis nepetifolia. [ABSTRACT FROM AUTHOR]

The urogenital system of male squamates consists of the testis, testicular ducts, and sexual segment of the kidney. These structures undergo seasonal variation, and their morphology is variable across taxa. Despite multiple studies examining the morphology of the various components of the reproductive system, few studies have examined squamates in sympatry. The purpose of this study was to investigate the morphology and seasonal variation of the reproductive system in two taxa that are sympatric with one another, Anolis carolinensis and Sceloporus undulatus, from southeastern Louisiana. Specimens were collected monthly for an entire year and processed for histological and ultrastructural analysis. Both species have a single rete testis leading from the testis to the ductuli efferentes, which leads into the proximal portion of the epididymis. The rete testis consists of a simple squamous epithelium with irregularly shaped nuclei, the ductuli efferentes consists of a ciliated simple cuboidal epithelium, and the epididymis a pseudostratified columnar epithelium. No differences were observed in the morphology of the urogenital systems between taxa but phenological variation was observed in terms of the tissue development for reproduction. Anolis carolinensis has an extended active period and two separated periods of maximal activity evidenced by two peaks in the ductuli efferentes epithelial height and tubular diameter (March and July) whereas Sceloporus undulatus only had a single peak occurring in June. These results suggest that reproductive morphology may be conserved at taxonomic levels above family level, and reproductive activity may be constrained phylogenetically and is not solely dependent on environmental factors, at least in terms of geographic range, though it is acknowledged that microhabitats may play a major role in cyclicity of reproductive events. Future studies examining species at various taxonomic levels, as well as species in sympatry, will provide additional insight into hypotheses concerning abiotic factors and reproductive biology. [ABSTRACT FROM AUTHOR]

Important scientific findings frequently arise from serendipitous findings. Unfortunately, many scientists are not prepared to take advantage of unexpected results and to question established paradigms, and this prevents them from capitalizing on their good fortune. In this essay, I first explain how pure serendipity led us to discover unusual modes of reproduction such as clonal reproduction by males and a green-beard gene. Next, I argue that the reproductive systems of ants and other organisms are probably much more diverse than is generally appreciated. This leads me to advocate for a new ‘molecular naturalist’ approach to reproductive systems and a more ‘naturalistic’ approach in population and evolutionary genetics. Finally, I make two further points. The first is that our current funding and education systems tend to hinder originality and curiosity. The other is that the field of ecology and evolution, and more generally all of science, would benefit from a shift in values from scientific productivity to scientific creativity. A few suggestions are made to this effect. [ABSTRACT FROM AUTHOR]

Apomixis sensu stricto (agamospermy) is asexual reproduction by seed. In angiosperms it represents an easy byway of life cycle renewal through gamete-like cells that give rise to maternal embryos without ploidy reduction (meiosis) and ploidy restitution (syngamy). The origin of apomixis still represents an unsolved problem, as it may be either evolved from sex or the other way around. This review deals with a reappraisal of the origin of apomixis in order to deepen knowledge on such asexual mode of reproduction which seems mainly lacking in the most basal angiosperm orders (i.e., Amborellales, Nymphaeales and Austrobaileyales, also known as ANA-grade), while it clearly occurs in different forms and variants in many unrelated families of monocots and eudicots. Overall findings strengthen the hypothesis that apomixis as a whole may have evolved multiple times in angiosperm evolution following different developmental pathways deviating to different extents from sexuality. Recent developments on the genetic control of apomixis in model species are also presented and adequately discussed in order to shed additional light on the antagonist theories of gain- and loss-of-function over sexuality. [ABSTRACT FROM AUTHOR]