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We studied the allocation of reproductive resources in 32 Mediterranean legume species. Correlations between main parameters were analysed at interspecific level. For each species we described the type of pollen presentation and examined its systematic significance. The high P/O values observed reflect low pollen transfer efficiency, typical of xenogamous species. Lowest P/Os were found in species with brush or explosive tripping mechanism, while highest ones were associated to primary pollen presentation. No trade-off was observed between P/O and the volume of a single pollen grain, nor between pollen number and pollen grain volume. Perennials showed higher P/Os compared to annuals, in accordance with the assumption that annual species are often self-compatible while most perennials are outcrossers. Fruit and seed set, evaluated in eight species under different experimental conditions, showed a close dependence on insects, and the existence of self-compatibility in three species ( Colutea arborescens, Coronilla emerus, Hedysarum coronarium). In Colutea arborescens and Coronilla emerus pollen-pistil interaction and pre-zygotic barriers to selfing were investigated through stigma receptivity tests and in-vivo pollen germination trials. Results demonstrated the importance of the stigmatic cuticle in reducing levels of autogamy. Productivity tests confirmed the utility of P/O ratio as indirect measure of species' breeding system. [ABSTRACT FROM AUTHOR]

Cytiseae have been reported to be mostly nectar-lacking, yet some taxa secrete nectar from extrastaminal nectaries. We studied the pollination biology of four shrubby species of Cytiseae (Cytisophyllum sessilifolium (L.) Lang, Spartium junceum L., Genista radiata (L.) Scop., Genista cilentina Valsecchi) which differ for ecology, distribution and population size. All species resulted obliged xenogamous, insect visits being necessary for successful pollination. Bumblebees and solitary bees are the principal pollinators, but also many beetles, some hover-flies, and few bugs visit flowers. Pollinator specificity is low, and this may be the reason of the scarce seed set compared to the number of ovules. Pollen is the main reward, but traces of glucose were detected in all species, at the base of vexillum or on the reproductive column. Nectar production is irregular in time, and apparently unpredictable. We suppose that nectar may play a role in attracting pollinators determining their right position for a successful pollination. [ABSTRACT FROM AUTHOR]

Abstract: To investigate the effects of two nectar nonprotein amino acids, β‐alanine and γ‐aminobutyric acid (GABA), on Osmia bicornis survival and locomotion, two groups of caged bees were fed with sugar syrup enriched with β‐alanine and GABA, respectively. A further control group was fed with sugar syrup. Five behavioural categories were chosen according to the principle of parsimony and intrinsic unitary consistency from start to end, and recorded by scan sampling: two states (remaining under paper or in tubes) and three events (walking on net, feeding from flower and flying). We also analysed the amino acid content of haemolymph sampled from an additional 45 bees fed the same diets (15 per diet type). Bees fed with β‐alanine had a significantly shorter survival time than those fed with the control and GABA diets. The GABA diet induced higher levels of locomotion than β‐alanine. The former nonprotein amino acid was only detected in the haemolymph of bees fed GABA. The results suggest that insects consuming nonprotein amino‐acid‐rich diets absorb and transfer these substances to the haemolymph and that nonprotein amino acids affect survival and locomotion. Ecological consequences are discussed in the framework of plant reproductive biology. [ABSTRACT FROM AUTHOR]

In recent decades, hundreds of secondary metabolites have been found in floral nectar and many studies have demonstrated that they can play various roles in modulating the behaviour of floral visitors. However, temporal variations in nectar chemistry over extended flowering seasons have never been substantiated. Moreover, the effects of nectar chemicals on insect behaviour are often studied under laboratory conditions, focusing on few insect species under artificial conditions which may influence insect responses. The aim of this exploratory study was to compare nectar chemistry and the durations of pollinator visits in the early and late summer periods of the long-flowering species Echium vulgare L. in natural populations. Nectar samples were collected in the early and late summer periods and insects were observed for a total of 480 min. The biogenic amine octopamine, sugars and the protein to non-protein amino acid ratio increased as the season proceeded. It remains to clarify whether these changes are determined by biotic and abiotic factors or whether the plant expresses some chemical constraint, however it seems likely that changes in nectar chemistry may be the cause of the longer visits by bumblebees to single flowers at the end of the flowering season. Though not conclusive, these results set a baseline for future research and highlight an interesting question. Since long-flowering plants see changing contexts during their bloom period, do they express chemical constraints to regulate their attractiveness? • Few studies explore nectar changes in long-flowering plants as the season advances. • Samples were collected from Echium vulgare populations in full and late bloom. • Nectar chemistry changes during the unfolding of the species flowering period. • Nectar octopamine is reported for the first time for Boraginaceae. • Octopamine increased suggesting a correlation with the duration of visit per flower. [ABSTRACT FROM AUTHOR]

The article reports talks about the leptin c.73T>C mutation and its effect on carcass traits in beef cattle. The experiment involved fifty-nine Blonde d'Aquitaine bulls and marbling was analysed as a quantitative trait. The authors suggest that the data on the effect of LEP on marbling are difficult to interpret due to differences in evaluation methods.

Knowledge about mixed mating systems can improve our understanding of the evolutionary dynamics of reproductive systems. Here we report a study of the floral and reproductive biology ofHypericum elodes, an Atlantic-European soft-water pools specialist which shows a floral architecture consistent with both self- and cross-pollination. Controlled pollination experiments were performed in a natural population during three consecutive years. Marked flowers were monitored until fruit production, and laboratory germination experiments were conducted with the seeds produced. Plants were self-compatible (SCI>0.75), however, compared with selfing, cross-pollination enhanced fruit-set, seed-set and seedling growth, but not seed germination. Inbreeding depression (δ) was mild in the pre-dispersal stages (δ = 0.22 for fruit set, 0.18 for seed set and 0.13 for seed mass), low for germination percentage (δ = 0.003) and mild for seedling growth (δ = 0.23). The breeding system ofH. elodespromotes outcrossing and assures reproductive success by means of competitive autogamy. Our results suggest a mixed mating strategy for the studied population, characterized by mild inbreeding depression (cumulative δ = 0.57), highlighting the benefit of this reproductive mode in unpredictable habitat, as the typical shallow-water meadows whereH. elodesgrows. [ABSTRACT FROM PUBLISHER]

The interplay between insect and plant traits outlines the patterns of pollen transfer and the subsequent plant reproductive fitness. We studied the factors that affect the pollination efficiency of a pollinator community of Dictamnus albus L. by evaluating insect behaviour and morphological characteristics in relation to flowering phenology. In order to extrapolate the pollinator importance of single taxa and of the whole pollinator guild, we calculated an index distinguishing between potential ( PPI) and realized ( RPI) pollinator importance. Although the pollinator species spectrum appeared rather constant, we found high intra- and inter-annual variability of pollinator frequency and importance within the insect community. Flower visitation rate strictly depended on insect abundance and on the overlap between their flying period and flower blooming. All the pollinators visited flowers from the bottom to the top of the racemes, excluding intra-plant geitonogamous pollination, and most of them showed high pollen fidelity. Only medium large-sized bees could contact the upward bending stiles while feeding on nectar, highlighting a specialisation of the plant towards bigger pollinators. Moreover, we found evidence of functional specialisation, since all pollinators were restricted to a single taxonomic group (order: Hymenoptera; superfamily: Apoidea). Both the PPI and RPI indices indicate Habropoda tarsata as the most important pollinator of D. albus. Following hand cross-pollination experiments we revealed the presence of pollination limitation in 1 of the 3 years of field study. We discuss this result in relation to flowering abundance and to possible mismatches of phenological periods between plants and insects. [ABSTRACT FROM AUTHOR]

Safeguarding crop pollination services requires the identification of the pollinator species involved and the provision of their ecological requirements at multiple spatial scales. However, the potential for agroecological intensification of pollinator-dependent crops by harnessing pollinator diversity is limited by our capacity to characterise the community of pollinator species for each crop, and to determine how it is influenced by the different survey methods used, as well as by climatic variables at larger geographic scales. Here, we surveyed wild bees using a standardised protocol at an unprecedented scale including 62 commercial apple orchards in Western and Central Europe (i) to validate recent findings on pollinator community divergence as measured by common survey methods (netting and pan trapping) using conventional and alternative biodiversity metrics (phylogenetic and functional diversity), and (ii) to investigate the impact of climatic variation on the patterns observed. Our results confirm the significant divergence in pollinator communities measured using the two common methods at the larger, sub-continental scale, and we provide evidence for a significant influence of climate on the magnitude of pollinator community divergence (beta diversity and its turnover component) between survey methods, particularly when comparing colder to warmer sites and regions. We also found that warmer sites are more dissimilar than colder sites in terms of species composition, functional traits, or phylogenetic affinities. This result probably stems from the comparatively larger species pool in Southern Europe and because apple flowers are accessible to a wide spectrum of pollinator species; hence, two distant survey localities in Southern Europe are more likely to differ significantly in their pollinator community. Collectively, our results demonstrate the spatially-varying patterns of pollinator communities associated with common survey methods along a climate gradient and at the sub-continental scale in Europe. • Netting and pan trapping showed distinct communities at a large-spatial scale. • Contrasting communities characterised by taxonomic, functional, and phylogenetic diversities. • Climate influences divergences between communities of both methods. • Divergence between communities increased in warmer regions (increasing temperatures). • A " filtering " effect is occurring in apple orchards in Europe. [ABSTRACT FROM AUTHOR]

Plants with multiple flowers could be prone to autonomous self-pollination and insect-mediated geitonogamy, but physiological and ecological features have evolved preventing costs related to autogamy. We studied the rare perennial herb Dictamnus albus as a model plant, with the aim of describing the plant-pollinator system from both plant and pollinator perspectives and analysing features that promote outcrossing in an entomophilous species. The breeding system and reproductive success of D. albus were investigated in experimental and natural conditions, showing that it is potentially self-compatible, but only intra-inflorescence insect-mediated selfing is possible. Nectar analysis showed gender-biased production towards the female phase, which follows the male phase, and during flowering, full blooming is found in flowers at the bottom of the raceme. Among a wide spectrum of insect visitors, three genera ( Bombus, Apis, Megachile) were found to be principal pollinators. A study of insect behaviour showed a tendency towards bottom-to-top flights for the most important pollinators Bombus spp. and Apis mellifera: upward movements on the racemes could be explained by foraging behaviour, from more to less rewarding flowers. In accordance with the 'declining reward hypothesis', bumblebees and honeybees leave the plant when gain of reward is low, after which few flowers are visited, reducing the chance of self-pollen transfer among flowers. Intra-flower self-pollination is prevented in D. albus by protandry and herkogamy, while the nectar-induced sequential pattern of pollinator visits avoids geitonogamy and tends to maximise pollen export, promoting outcrossing. All these features for preventing selfing benefit plant fitness and population genetic structure. [ABSTRACT FROM AUTHOR]

Disassortative mating in distylous self-incompatible species should result in the equilibrium of morph types in natural populations. Deviation from isoplethy may affect pollen transfer, and in isolated populations it could lead to Allee effect and genetic drift. Pollen limitation has been found to occur in several distylous species, for which mating opportunities are actually reduced to half population. In this study, we investigated the reproductive features and pollination ecology of the narrow endemic Primula apennina. We recorded equilibrium of morph frequencies in the studied population, reflecting the comparable fecundity found in the two morphs. Long-styled flowers produce more pollen grains of smaller size than short-styled ones: we hypothesize that in thrum flowers, pollen is more easily removed by the insect pollinator Macroglossum stellatarum, resulting in equal pollen amounts carried to both short styles and long styles. This lower pollen transfer efficiency from long-styled to short-styled flowers is also reflected in legitimate pollen-ovule ratio values. Despite results show no evidence of imminent threats to population persistence at study site, the strict dependence on one or very few pollinator species, and ecological traits, may increase extinction risks in the long-term period. [ABSTRACT FROM AUTHOR]

Two points are controversial in the anatomy of the mesorectum: (1) its origin; and (2) the existence of the lateral ligaments. We studied these structures in animals and in human fetuses. Dissections were performed on quadrupedal mammals (29 dogs and 32 pigs) and 28 primates (Macaca apes). Moreover, macroslices of Macaca ape and of 182 human fetuses were examined histologically. In quadrupedal mammals, we found no traces of any adipose masses comparable to the human mesorectum nor were there ligaments of suspension. In the ape, the adipose tissue in the mesosigmoid forms an adipose cuff that completely surrounds the extraperitoneal rectum. Two dense connective bands were found between the lateral wall of the pelvis and the perirectal tissue. Both the mesorectum and the lateral ligaments were clearly identified in the sections of human fetus only at the end of the fifth month but not earlier. On the basis of our analysis of 3 animal species, we conclude that the mesorectum and lateral ligaments are absent in quadrupedal mammals but are present in primates. Therefore, we hypothesize that these structures appeared with the attainment of the upright position, even though other hypotheses are possible. [ABSTRACT FROM AUTHOR]