Performance, Effectiveness, and Efficiency of Honeybees as Pollinators of Coffea arabica (Gentianales, Rubiaceae).

Studies in crop plants analyzing floral biology in conjunction with effectiveness and efficiency of pollinators on pollen transfer and fruit formation are not common, although they are essential to provide better management actions. On this base, we selected a farm in Bahia, Brazil, to study pollination on coffee plants (Coffea arabica L.). Specifically, we want to analyze if nectar traits influence visitor's performance throughout flower lifetime and if honeybees (Apis mellifera scutellata Lepeletier, 1836) are effective and efficient for coffee pollination comparing fertilization and fructification among four experimental treatments: open (OP), wind (WP), cross (HCP), and single-visit bee pollination (SVBP). We found that honeybees collect both nectar and pollen from coffee flowers and transfer pollen on stigmas even after one visit. No differences were found among treatments regarding the number of pollen grains transferred on the stigmas (effectiveness). OP flowers showed a comparative lower efficiency (pollen tubes and fruit set) probably due to pollination failure as those flowers have a higher variability on the number of deposited pollen grains. Two of the treatments (HCP and SVBP) showed higher fertilization (measuring tubes until the end of the style). Pollen loads seem to be limited by a peak of pollen transference by pollinators, followed by the stabilization in the number of pollen grains deposited per stigma. Thus, reproduction of the coffee can be limited by the quality of pollen grains moved by pollinators instead of quantity. Management strategies should focus on monitoring bee density on plants for increasing pollen quality transfer on flowers trough maintaining the adequate proportions of seminatural habitats and/or the number of hives on agricultural fields according to the flowering of the crop.

Evidence suggesting interactions between immunodominant membrane protein Imp of Flavescence dorée phytoplasma and protein extracts from distantly related insect species.

AIMS: In this study, binding between the immunodominant membrane protein Imp of the 16SrV-D phytoplasma associated with Flavescence dorée disease (FD-Dp) and insect proteins of vectors and non-vectors of FD-Dp was tested. METHODS AND RESULTS: Six Auchenorrhyncha species, from distantly related groups were selected: Scaphoideus titanus, Euscelidius variegatus, Macrosteles quadripunctulatus, Zyginidia pullula (Cicadomorpha), Ricania speculum and Metcalfa pruinosa (Fulgoromorpha). The vector status of each species was retrieved from the literature or determined by transmission trials in this study. A His-tagged partial Imp protein and a rabbit polyclonal antibody were synthesized and used for Western and Far-Western dot Blot (FWdB) experiments. Total native and membrane proteins (MP) were extracted from entire bodies and organs (gut and salivary glands) of each insect species. FWdB showed decreasing interaction intensities of Imp fusion protein with total proteins from entire bodies of S. titanus, E. variegatus (competent vectors) and M. quadripunctulatus (non-vector), while no interaction signal was detected with the other three species (non-vectors). A strong signal detected upon interaction of FD-D Imp and MP from guts of closely related insects supports the role of this organ as the first barrier to ensure successful transmission. CONCLUSIONS: Our results showed that specific Imp binding, correlated with vector status, is involved in interactions between FD-Dp and insect proteins. SIGNIFICANCE AND IMPACT OF THE STUDY: Integrating knowledge on host-pathogen protein-protein interactions and on insect phylogeny would help to identify the actual range of vectors of phytoplasma strains of economic importance.

Retraction notice to "Fungal diversity is negatively affected by habitat fragmentation: a meta-analysis" [Current Opinion in Microbiology 37 (2017) 61-66].

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article that has already been published in , http://dx.doi.org/10.1016/j.mib.2017.03.015 has been withdrawn at the request of the editor and publisher. The publisher regrets that an error occurred which led to the premature publication of this paper. This error bears no reflection on the article or its authors. The publisher apologizes to the authors and the readers for this unfortunate error.

Fungal diversity at fragmented landscapes: synthesis and future perspectives.

Fungi are organisms with important roles in ecosystem functioning and services, but knowledge about how habitat fragmentation affect fungal diversity is biased by experimental approaches and it is spread in different trophic groups. We analyzed the empirical evidences of fungal diversity in fragmented landscapes, and proposed future perspectives for the study of these organisms under land use changes. Fungal diversity might be negatively affected by habitat fragmentation; however, this trend may differ in magnitude depending on fungal groups and their nutritional habits. In addition, due to the fact that fungal diversity at fragmented landscapes has been studied mainly through few indicators (e.g. isolation, area and edge effect); we propose incorporating the landscape structure and accurate spatio-temporal scales to the study of fungal diversity responses to fragmented landscapes. Together, this methodological refinement may allow improving knowledge on fungi when designing proper strategies for landscape management.

WITHDRAWN: Fungal diversity is negatively affected by habitat fragmentation: a meta-analysis.

This article that has already been published in , 10.1016/j.mib.2017.03.015 has been withdrawn at the request of the editor and publisher. The publisher regrets that an error occurred which led to the premature publication of this paper. This error bears no reflection on the article or its authors. The publisher apologizes to the authors and the readers for this unfortunate error". The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

Functional decoupling between flowers and leaves in the Ameroglossum pernambucense complex can facilitate local adaptation across a pollinator and climatic heterogeneous landscape.

Decoupling between floral and leaf traits is expected in plants with specialized pollination systems to assure a precise flower-pollinator fit, irrespective of leaf variation associated with environmental heterogeneity (functional modularity). Nonetheless, developmental interactions among floral traits also decouple flowers from leaves regardless of selection pressures (developmental modularity). We tested functional modularity in the hummingbird-pollinated flowers of the Ameroglossum pernambucense complex while controlling for developmental modularity. Using two functional traits responsible for flower-pollinator fit [floral tube length (TL) and anther-nectary distance (AN)], one floral trait not linked to pollination [sepal length (SL), control for developmental modularity] and one leaf trait [leaf length (LL)], we found evidence of flower functional modularity. Covariation between TL and AN was ca. two-fold higher than the covariation of either of these traits with sepal and leaf lengths, and variations in TL and AN, important for a precise flower-pollinator fit, were smaller than SL and LL variations. Furthermore, we show that previously reported among-population variation of flowers associated with local pollinator phenotypes was independent from SL and LL variations. These results suggest that TL and AN are functionally linked to fit pollinators and sufficiently decoupled from developmentally related floral traits (SL) and vegetative traits (LL). These results support previous evidences of population differentiation due to local adaptation in the A. pernambucense complex and shed light on the role of flower-leaf decoupling for local adaptation in species distributed across biotic and abiotic heterogeneous landscapes.

Decreasing global transcript levels over time suggest that phytoplasma cells enter stationary phase during plant and insect colonization.

To highlight different transcriptional behaviors of the phytoplasma in the plant and animal host, expression of 14 genes of "Candidatus Phytoplasma asteris," chrysanthemum yellows strain, was investigated at different times following the infection of a plant host (Arabidopsis thaliana) and two insect vector species (Macrosteles quadripunctulatus and Euscelidius variegatus). Target genes were selected among those encoding antigenic membrane proteins, membrane transporters, secreted proteins, and general enzymes. Transcripts were detected for all analyzed genes in the three hosts; in particular, those encoding the antigenic membrane protein Amp, elements of the mechanosensitive channel, and two of the four secreted proteins (SAP54 and TENGU) were highly accumulated, suggesting that they play important roles in phytoplasma physiology during the infection cycle. Most transcripts were present at higher abundance in the plant host than in the insect hosts. Generally, transcript levels of the selected genes decreased significantly during infection of A. thaliana and M. quadripunctulatus but were more constant in E. variegatus. Such decreases may be explained by the fact that only a fraction of the phytoplasma population was transcribing, while the remaining part was aging to a stationary phase. This strategy might improve long-term survival, thereby increasing the likelihood that the pathogen may be acquired by a vector and/or inoculated to a healthy plant.

Nectar secretion dynamic links pollinator behavior to consequences for plant reproductive success in the ornithophilous mistletoe Psittacanthus robustus.

The mistletoe Psittacanthus robustus was studied as a model to link flower phenology and nectar secretion strategy to pollinator behaviour and the reproductive consequences for the plant. The bright-coloured flowers presented diurnal anthesis, opened asynchronously throughout the rainy season and produced copious dilute nectar as the main reward for pollinators. Most nectar was secreted just after flower opening, with little sugar replenishment after experimental removals. During the second day of anthesis in bagged flowers, the flowers quickly reabsorbed the offered nectar. Low values of nectar standing crop recorded in open flowers can be linked with high visitation rates by bird pollinators. Eight hummingbirds and two passerines were observed as potential pollinators. The most frequent flower visitors were the hummingbirds Eupetomena macroura and Colibri serrirostris, which actively defended flowering mistletoes. The spatial separation between anthers, stigma and nectar chamber promotes pollen deposition on flapping wings of hovering hummingbirds that usually probe many flowers per visit. Seed set did not differ between hand-, self- and cross-pollinated flowers, but these treatments set significantly more seeds than flowers naturally exposed to flower visitors. We suggest that the limitation observed in the reproductive success of this plant is not related to pollinator scarcity, but probably to the extreme frequency of visitation by territorial hummingbirds. We conclude that the costs and benefits of plant reproduction depend on the interaction strength between flowers and pollinators, and the assessment of nectar secretion dynamics, pollinator behaviour and plant breeding system allows clarification of the complexity of such associations.

Beyond the pollination syndrome: nectar ecology and the role of diurnal and nocturnal pollinators in the reproductive success of Inga sessilis (Fabaceae).

Inga species present brush-type flower morphology allowing them to be visited by distinct groups of pollinators. Nectar features in relation to the main pollinators have seldom been studied in this genus. To test the hypothesis of floral adaptation to both diurnal and nocturnal pollinators, we studied the pollination ecology of Inga sessilis, with emphasis on the nectar secretion patterns, effects of sequential removals on nectar production, sugar composition and the role of diurnal and nocturnal pollinators in its reproductive success. Inga sessilis is self-incompatible and pollinated by hummingbirds, hawkmoths and bats. Fruit set under natural conditions is very low despite the fact that most stigmas receive polyads with sufficient pollen to fertilise all ovules in a flower. Nectar secretion starts in the bud stage and flowers continually secreting nectar for a period of 8 h. Flowers actively reabsorbed the nectar a few hours before senescence. Sugar production increased after nectar removal, especially when flowers were drained during the night. Nectar sugar composition changed over flower life span, from sucrose-dominant (just after flower opening, when hummingbirds were the main visitors) to hexose-rich (throughout the night, when bats and hawkmoths were the main visitors). Diurnal pollinators contributed less than nocturnal ones to fruit production, but the former were more constant and reliable visitors through time. Our results indicate I. sessilis has floral adaptations, beyond the morphology, that encompass both diurnal and nocturnal pollinator requirements, suggesting a complementary and mixed pollination system.

Nectar regulation in Euphorbia tithymaloides L., a hummingbird-pollinated Euphorbiaceae.

Floral sexual phases can differ in nectar production and might be under selective pressure by pollinators. We studied Euphorbia tithymaloides, which has inflorescences that are initially female and then hermaphroditic. Volume and concentration of nectar were measured in both stages. Nectar production and the effect of extractions were determined using sets of bagged inflorescences; inflorescences in the hermaphroditic phase had higher values of nectar concentration, volume and sugar mass than inflorescences in the female phase. Nectar resorption was detected in senescent inflorescences. To test for homeostatic nectar regulation, artificial nectar was added and the response assessed after 24 h. The experiments showed that concentration and sugar mass are regulated within a narrow range, and the homeostatic points differ between the two sexual phases. These differences in nectar can be detected by hummingbirds, which prefer the female stage. Resorption and secretion seem to be part of a homeostatic mechanism by which nectar attributes are maintained to optimise sugar recovery.

Host plant determines the phytoplasma transmission competence of Empoasca decipiens (Hemiptera: Cicadellidae).

Phytoplasmas are phloem-restricted plant pathogens transmitted by leafhoppers, planthoppers, and psyllids (Hemiptera). Most known phytoplasma vectors belong to the Cicadellidae, but many are still unknown. Within this family, Empoasca spp. (Typhlocybinae) have tested positive for the presence of some phytoplasmas, and phytoplasma transmission has been proven for one species. The aim of this work was to investigate the ability of Empoasca decipiens Paoli in transmitting chrysanthemum yellows phytoplasma (CYP, "Candidatus Phytoplasma asteris", 16SrI-B) and Flavescence dorée phytoplasma (FDP, 16SrV-C) to Chrysanthemum carinatum Schousboe (tricolor daisy) and Viciafaba (L.) (broad bean). Euscelidius variegatus Kirschbaum, a known vector of CYP and FDP, was caged together with Em. decipiens on the same source plants as a positive control of acquisition. Em. decipiens acquired CYP from daisies, but not from broad beans, and inoculated the pathogen to daisies with alow efficiency, but not to broad beans. Em. decipiens did not acquire FDP from the broad bean source. Consistent with the low transmission rate, CYP was found in the salivary glands of very few phytoplasma-infected Em. decipiens, indicating these organs represent a barrier to phytoplasma colonization. In the same experiments, the vector Eu. variegatus efficiently acquired both phytoplasmas, and consistently CYP was detected in the salivary glands of most samples of this species. The identity of the CYP strain in leafhoppers and plants was confirmed by polymerase chain reaction (PCR)-restriction fragment length polymorphism. The CYP titer in Em. decipiens was monitored over time by real-time PCR. The damage caused by Em. decipiens feeding punctures was depicted. Differences in feeding behavior on different plant species may explain the different phytoplasma transmission capability. Em. decipiens proved to be an experimental vector of CYP.

Interrelationships between "Candidatus Phytoplasma asteris" and its leafhopper vectors (Homoptera: Cicadellidae).

The titer of chrysanthemum yellows phytoplasma (CYP, "Candidatus Phytoplasma asteris") in the three vector species Euscelis incisus Kirschbaum, Euscelidius variegatus Kirschbaum, and Macrosteles quadripunctulatus Kirschbaum (Homoptera: Cicadellidae) was measured after controlled acquisition from infected Chrysanthemum carinatum (Schousboe) (daisy) plants. Phytoplasma DNA was quantified in relation to insect DNA (genome units [GU] of phytoplasma DNA per ng of insect DNA) by using a quantitative real-time polymerase chain reaction (PCR) procedure. The increase in phytoplasma titer recorded in hoppers after they were transferred to plants that were nonhosts for CYP provides definitive evidence for phytoplasma multiplication in leafhoppers. CYP multiplication over time in M. quadripunctulatus was much faster than in E. incisus and E. variegatus. CYP titer was also highest in M. quadripunctulatus, and this was reflected in the latent period in the insect. The mean latent period of CYP in M. quadripunctulatus was 18 d versus 30 d in E. variegatus. M. quadripunctulatus was the most efficient vector, giving 100% transmission for single insects compared with 75-82% for E. incisus or E. variegatus, respectively. By sequential transmission, we analyzed the time course of transmission: E. variegatus were persistently infective for life or until shortly before death. Occasionally, leafhoppers failed to maintain continuity of infectivity even after completion of the latent period. PCR analysis of transmitter and nontransmitter E. variegatus adults showed that some nontransmitters were CYP positive, whereas others were CYP negative. These findings suggest that both midgut and salivary gland barriers play a role in transmission efficiency.

FMECA methodology applied to two pathways in an orthopaedic hospital in Milan.

INTRODUCTION: Adverse events pose a challenge to medical management: they can produce mild or transient disabilities or lead to permanent disabilities or even death; preventable adverse events result from error or equipment failure. METHODS: IRCCS Istituto Ortopedico Galeazzi implemented a clinical risk management program in order to study the epidemiology of adverse events and to improve new pathways for preventing clinical errors: a risk management FMECA-FMEA pro-active analysis was applied either to an existing clinical support pathway or to a new process before its implementation. RESULTS: The application of FMEA-FMECA allowed the clinical risk unit of our hospital to undertake corrective actions in order to reduce the adverse events and errors on high-risk procedure used inside the hospitals.