| use of nucleotide sequence data to identify a microsporidian pathogen of pieris rapae (lepidoptera, pieridae). | nucleotide sequence was determined for a portion of genomic dna which spans the v4 variable region of the small subunit ribosomal rna gene of an unidentified microsporidium from the cabbage white butterfly, pieris rapae (174 base pairs). comparison with equivalent sequence data obtained here for two other microsporidian species, nosema bombycis (240 base pairs) and nosema bombi (200 base pairs), and from the genbank database for 11 other microsporidian species suggests that the unidentified spec ... | 1996 | 8931362 |
| effects of nosema bombi and its treatment fumagillin on bumble bee (bombus occidentalis) colonies. | we examined the effects of nosema bombi (microsporidia: nosematidae) on colonies of bumble bees, bombus occidentalis greene (hymenoptera: apidae), used to pollinate tomatoes in commercial greenhouses. we assessed methods of detecting n. bombi and tested the effectiveness of fumagillin to control this parasite. n. bombi did not affect adult population size or amount of brood in b. occidentalis colonies. fumagillin was not effective against n. bombi at the doses we tested, and frass samples did no ... | 2003 | 13678713 |
| fixation of microsporidian spores for electron microscopy. | fresh and frozen spores of the microsporidia nosema apis and nosema bombi were fixed using various fixatives at different times and temperatures. paraformaldehyde and technical formaldehyde gave results comparable to or better than glutaraldehyde. increased fixation temperature improved the fixation of spores from terrestrial hosts. freezing did not destroy the cytology of the spore. | 2005 | 16112682 |
| complete rrna gene sequences reveal that the microsporidium nosema bombi infects diverse bumblebee (bombus spp.) hosts and contains multiple polymorphic sites. | characterisation of microsporidian species and differentiation among genetic variants of the same species has typically relied on ribosomal rna (rrna) gene sequences. we characterised the entire rrna gene of a microsporidium from 11 isolates representing eight different european bumblebee (bombus) species. we demonstrate that the microsporidium nosema bombi infected all hosts that originated from a wide geographic area. a total of 16 variable sites (all single nucleotid polymorphisms (snps)) was ... | 2005 | 16313443 |
| specific and sensitive detection of nosema bombi (microsporidia: nosematidae) in bumble bees (bombus spp.; hymenoptera: apidae) by pcr of partial rrna gene sequences. | a polymerase chain reaction (pcr) based method was developed for the specific and sensitive diagnosis of the microsporidian parasite nosema bombi in bumble bees (bombus spp.). four primer pairs, amplifying ribosomal rna (rrna) gene fragments, were tested on n. bombi and the related microsporidia nosema apis and nosema ceranae, both of which infect honey bees. only primer pair nbombi-ssu-jf1/jr1 could distinguish n. bombi (323bp amplicon) from these other bee parasites. primer pairs nbombi-ssu-jf ... | 2006 | 16376373 |
| cytological variation and pathogenicity of the bumble bee parasite nosema bombi (microspora, nosematidae). | in three field seasons, 2003-2005, bumble bees were collected in southern sweden and eastern denmark in search of microsporidian parasites. of the 16 bumble bee species studied, microsporidia were found in bombus hortorum, bombus hypnorum, bombus lapidarius, bombus lucorum, bombus pascuorum, bombus pratorum, bombus ruderarius, bombus subterraneus and bombus terrestris. only one microsporidian species, nosema bombi, was recorded. a microsporidium found in b. pratorum differed cytologically from m ... | 2007 | 17005191 |
| multiple rrna variants in a single spore of the microsporidian nosema bombi. | to understand the source of the multiple dna sequence variants of nosema bombi ribosomal rna (rrna) found in a single bumble bee host, we pcr amplified, cloned, and sequenced the partial rrna gene from 125 clones, which were derived from four out of 46 spores individually isolated from a single host by laser microdissection. at least two rrna variants, characterized by either (gttt)(2) or (gttt)(3) repeat units within the internal transcribed spacer (its) region, were found per spore in approxim ... | 2007 | 17300528 |
| nosema bombi: a pollinator parasite with detrimental fitness effects. | nosema bombi is an obligate intracellular parasite that infects different bumblebee species at a substantial, though variable, rate. to date its pathology and impact on host fitness are not well understood. we performed a laboratory experiment investigating the pathology and fitness effects of this parasite on the bumblebee bombus terrestris. we experimentally infected one group of colonies with n. bombi spores at the start of the worker production, while a second uninfected group of colonies se ... | 2007 | 17482641 |
| horizontal transmission success of nosema bombi to its adult bumble bee hosts: effects of dosage, spore source and host age. | parasite transmission dynamics are fundamental to explaining the evolutionary epidemiology of disease because transmission and virulence are tightly linked. horizontal transmission of microsporidian parasites, e.g. nosema bombi, may be influenced by numerous factors, including inoculation dose, host susceptibility and host population heterogeneity. despite previous studies of n. bombi and its bumble bee hosts, neither the epidemiology nor impact of the parasite are as yet understood. here we inv ... | 2007 | 17610765 |
| cophylogeny of nosema (microsporidia: nosematidae) and bees (hymenoptera: apidae) suggests both cospeciation and a host-switch. | some microsporidian parasites belonging to the genus nosema infect bees. previous phylogenies of these parasites have produced alternative, conflicting relationships. we analyzed separately, and in combination, large and small subunit ribosomal dna sequences of nosema species infecting bees under neighbor-joining, maximum parsimony, maximum likelihood, and bayesian frameworks. we observed a sister relationship between nosema ceranae and nosema bombi, with nosema apis as a basal member to this gr ... | 2009 | 18684016 |
| identification of nosema bombi fantham and porter 1914 (microsporidia) in bombus impatiens and bombus sandersoni from great smoky mountains national park (usa). | ninety three bumble bees belonging to the genus bombus, subgenus pyrobombus (three bombus vagans, seven bombus bimaculatus, 17 b. sandersoni and 68 b. impatiens) from great smoky mountains national park were examined for microsporidia. light microscopy of calcoflour and trichrome-stained smears, and pcr revealed infection with n. bombi in one specimen each of b. sandersoni and b. impatiens. sizes and shapes of spores in both n. bombi isolates were similar to those described for european isolates ... | 2010 | 19835879 |
| patterns of widespread decline in north american bumble bees. | bumble bees (bombus) are vitally important pollinators of wild plants and agricultural crops worldwide. fragmentary observations, however, have suggested population declines in several north american species. despite rising concern over these observations in the united states, highlighted in a recent national academy of sciences report, a national assessment of the geographic scope and possible causal factors of bumble bee decline is lacking. here, we report results of a 3-y interdisciplinary st ... | 2011 | 21199943 |
| effects of invasive parasites on bumble bee declines. | bumble bees are a group of pollinators that are both ecologically and economically important and declining worldwide. numerous mechanisms could be behind this decline, and the spread of parasites from commercial colonies into wild populations has been implicated recently in north america. commercial breeding may lead to declines because commercial colonies may have high parasite loads, which can lead to colonization of native bumble bee populations; commercial rearing may allow higher parasite v ... | 2011 | 21771075 |
| Diversity of Nosema associated with bumblebees (Bombus spp.) from China. | Bumblebees (Bombus spp.) are important pollinators of many economically important crops and microsporidia are among the most important infections of these hosts. Using molecular markers, we screened a large sample (n=1,009 bees) of workers of 27 different Bombus spp. from China (Sichuan, Qinghai, Inner Mongolia, and Gansu provinces). The results showed that 62 individuals representing 12 Bombus spp. were infected by microsporidia with an overall prevalence of 6.1%. Based on the haplotypes (ssrRN ... | 2012 | 22138016 |
| interspecific geographic distribution and variation of the pathogens nosema bombi and crithidia species in united states bumble bee populations. | several bumble bee (bombus) species in north america have undergone range reductions and rapid declines in relative abundance. pathogens have been suggested as causal factors, however, baseline data on pathogen distributions in a large number of bumble bee species have not been available to test this hypothesis. in a nationwide survey of the us, nearly 10,000 specimens of 36 bumble bee species collected at 284 sites were evaluated for the presence and prevalence of two known bombus pathogens, th ... | 2011 | 22119631 |
| comparative analysis of detection limits and specificity of molecular diagnostic markers for three pathogens (microsporidia, nosema spp.) in the key pollinators apis mellifera and bombus terrestris. | global pollinator decline has recently been discussed in the context of honey and bumble bee infections from various pathogens including viruses, bacteria, microsporidia and mites. the microsporidian pathogens nosema apis, nosema ceranae and nosema bombi may in fact be major candidates contributing to this decline. different molecular and non-molecular detection methods have been developed; however, a comparison, especially of the highly sensitive pcr based methods, is currently lacking. here, w ... | 2011 | 21927870 |
| evaluation of large-scale dissemination of nosema ceranae spores by european bee-eaters merops apiaster. | identification of transmission routes and of factors affecting the spatial positions of pathogens, hosts and vectors is basic to an adequate disease management. nosema ceranae is a microsporidian recently described as a parasite of apis mellifera honeybees and is currently considered the aetiological agent of an emergent illness named nosemosis type c. in this article we evaluate the role of a bird species, the european bee-eater, merops apiaster, as a large-scale dispersive agent of n. ceranae. ... | 2011 | 23761230 |
| long-term prevalence of the protists crithidia bombi and apicystis bombi and detection of the microsporidium nosema bombi in invasive bumble bees. | an initial survey in 2009 carried out at a site in northwestern patagonia region, argentina, revealed for the first time in south america the presence of the flagellate crithidia bombi and the neogregarine apicystis bombi, two pathogens associated with the palaearctic invasive bumble bee bombus terrestris. in order to determine the long-term persistence and dynamics of this microparasite complex, four additional collections at the same site (san carlos de bariloche) were conducted along the foll ... | 2017 | 28085231 |
| the relationship between managed bees and the prevalence of parasites in bumblebees. | honey bees and, more recently, bumblebees have been domesticated and are now managed commercially primarily for crop pollination, mixing with wild pollinators during foraging on shared flower resources. there is mounting evidence that managed honey bees or commercially produced bumblebees may affect the health of wild pollinators such as bumblebees by increasing competition for resources and the prevalence of parasites in wild bees. here we screened 764 bumblebees from around five greenhouses th ... | 2014 | 25165632 |
| pollination services enhanced with urbanization despite increasing pollinator parasitism. | animal-mediated pollination is required for the reproduction of the majority of angiosperms, and pollinators are therefore essential for ecosystem functioning and the economy. two major threats to insect pollinators are anthropogenic land-use change and the spread of pathogens, whose effects may interact to impact pollination. here, we investigated the relative effects on the ecosystem service of pollination of (i) land-use change brought on by agriculture and urbanization as well as (ii) the pr ... | 2016 | 27335419 |
| indirect effects on mutualisms: parasitism of bumble bees and pollination service to plants. | researchers increasingly recognize the important role of mutualisms in structuring communities and view positive interactions in a community context rather than as simple pairwise interactions. indirect effects, such as those that predators have on lower trophic levels, are a key process in community ecology. however, such top-down indirect effects have rarely been extended to mutualisms. antagonists of one mutualist have the potential to negatively affect the second mutualist through negative e ... | 2013 | 23691664 |
| ecological effects on gut bacterial communities in wild bumblebee colonies. | 1. animal hosts harbour diverse and often specific bacterial communities (microbiota) in their gut. these microbiota can provide crucial services to the host such as aiding in digestion of food and immune defence. however, the ecological factors correlating with and eventually shaping these microbiota under natural conditions are poorly understood. 2. bumblebees have recently been shown to possess simple and highly specific microbiota. we here examine the dynamics of these microbiota in field co ... | 2012 | 22708631 |
| test of the invasive pathogen hypothesis of bumble bee decline in north america. | emergent fungal diseases are critical factors in global biodiversity declines. the fungal pathogennosema bombiwas recently found to be widespread in declining species of north american bumble bees (bombus), with circumstantial evidence suggesting an exotic introduction from europe. this interpretation has been hampered by a lack of knowledge of global genetic variation, geographic origin, and changing prevalence patterns ofn. bombiin declining north american populations. thus, the temporal and s ... | 2016 | 27044096 |
| distribution and diversity of nosema bombi (microsporidia: nosematidae) in the natural populations of bumblebees (bombus spp.) from west siberia. | nosema bombi is an obligate intracellular parasite of bumblebees (hymenoptera, bombus spp.), which has significant negative effect on individual bumblebees, colony fitness, and development. recently, several new genetic variants of n. bombi without a defined taxonomic status were identified in natural bumblebee populations from russia, china, and several european countries, as well as n. ceranae, originally isolated from honey bees, was described in bumblebee species. thus, it is required to inv ... | 2015 | 26063531 |
| pcr reveals high prevalence of non/low sporulating nosema bombi (microsporidia) infections in bumble bees (bombus) in northern arizona. | about 20% of bumble bee species are in decline in north america, and the microsporidian pathogen, nosema bombi, has been correlated with these declines. we conducted a comprehensive survey of n. bombi infections in the bumble bee communities throughout the flight season along an elevation gradient in northern arizona. focusing on two species, bombus (pyrobombus) huntii and bombus (pyrobombus) centralis, we used a combination of pcr and microscopy to distinguish between sporulating and non/low, s ... | 2014 | 25219370 |
| nosema adaliae sp. nov., a new microsporidian pathogen from the two-spotted lady beetle, adalia bipunctata l. (coleoptera: coccinellidae) and its relationship to microsporidia that infect other coccinellids. | the two-spotted lady beetle, adalia bipunctata l., is a tree-dwelling lady beetle endemic to parts of europe, central asia and north america that is commercially available for aphid control in europe and north america. lady beetles host a wide variety of symbionts including parasitoids, viruses, eugregarines, fungi, bacteria, nematodes and microsporidia. four species of microsporidia have been described from lady beetles, and an undescribed microsporidium was recently isolated from local populat ... | 2014 | 24135414 |
| factors influencing nosema bombi infections in natural populations of bombus terrestris (hymenoptera: apidae). | bumblebees are of profound ecological importance because of the pollination services they provide in natural and agricultural ecosystems. any decline of these pollinators is therefore of great concern for ecosystem functioning. increased parasite pressures have been discussed as a major factor for the loss of pollinators. one of the main parasites of bumblebees is nosema bombi, an intracellular microsporidian parasite with considerable impact on the vitality of the host. here we study the effect ... | 2012 | 22349145 |
| microsporidia: an emerging threat to bumblebees? | microsporidia may cause emerging infectious diseases (eids) in bumblebees. two drivers - commercial bumblebees and managed honey bees - have been identified as possible sources of pathogen spillover. in addition, declines in bumblebee populations may have led to lower genetic diversity and subsequent higher susceptibility to infection, enabling microsporidia to increase in prevalence. there is strong evidence for relatively recent increases in the prevalence of nosema bombi in north america. how ... | 2017 | 28663099 |