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The European honey bee (Apis mellifera) is an important livestock animal in New Zealand. This is due to their combined pollination services and production of honey for export, notably mānuka honey. The honey bee is an imported species that is praised as a productive partner and accused as an invasive competitive species. In New Zealand this well–entrenched insect pollinator has essentially been driven to extinction outside of managed apiaries by the deadly Varroa mite (Varroa destructor). Honey bees, live in a microbial world which includes beneficial microorganisms and pathogens that cause disease. Here we review the biology and prevention of Paenibacillus larvae which causes American Foulbrood (AFB). AFB affected hives must be destroyed within seven days of discovery. Bacteriophages, the viruses of bacteria, are abundant in nature and demonstrated to protect hives against AFB infection when applied in advance of exposure. Whilst treating AFB is not allowed, P. larvae bacteriophages can be a safe and natural prophylactic for protecting honey bee colonies against AFB infection. Bacteriophages are a potent source of novel solutions to agricultural diseases caused by bacterial pathogens, and we are proponents of their development to protect our domesticated pollinators against AFB here in Aotearoa, New Zealand. [ABSTRACT FROM AUTHOR]

Pollination patterns i.e. the proportions of entomophilous, anemophilous, autogamous and hydrophilous plant species and those useful for the European honey bee (Apis mellifera L.) in the flora and vegetation of northern Croatia have been determined. The survey included 507 plant taxa, belonging to 95 plant families. The results show that most plant species employ insect pollination (73.6%), followed by self-pollination (30%), wind (25%) and water pollination (0.6%). For some plant species there are one, two or more modes of pollination; the largest group consists of pure insect pollination (43%), followed by both insect and self-pollination (27%), pure wind pollination (22%), insect and wind pollination (2.6%), and so on. Overall, 54% of plant species useful to European honey bees were found, 51% of which provide pollen and 47% nectar. These results suggest that A. mellifera could be a potential pollinator for about half of the flora. Analysis shows significant differences in pollination patterns among habitat types and that most entomophilous plant taxa are found in grassland, forest and ruderal sites, indicating that these habitats are most important for pollinators. Other characteristics of plant species, such as flowering time, plant family, life form and origin, were also analysed to determine a possible relationship with pollination. [ABSTRACT FROM AUTHOR]

Bahiagrass (Paspalum notatum Flüggé; Poaceae) is primarily a pasture grass in the southern US. It is also lawn grass found in residential settings, public parks, and planted in golf courses. Bahiagrass is principally wind-pollinated, but the pollination contribution of insect pollinators is not documented. A survey was conducted on bahiagrass patches in central Georgia, USA, to determine the visitation of foraging pollinators. The results showed that European honey bees, bumblebees, and sweat bees forage on bahiagrass spikelets. Of the total bees observed, 10.6% (n = 94) were foraging on bahiagrass, compared to 46.8% on white clover, 27.7% on dandelion, and 14.8% on buckhorn plantain. This is the first report showing bee foraging on bahiagrass. The results suggest that bahiagrass spikelets may be a supplemental resource for bees and essential for bee conservation programs in rural and suburban areas. More research is warranted to determine how bahiagrass spikelets play a role in meeting the nutritional needs of bees to help sustain their colony and provide pollination service. [ABSTRACT FROM AUTHOR]

Staminodes are infertile stamens that have evolved numerous times across angiosperms; however, little is known about the evolutionary transitions of staminodes, especially among close relatives. We studied staminode evolution in Mentzelia section Bartonia to determine how many times staminodes have been gained or lost. A maximum-likelihood approach identified ten transitions, in which staminodes evolved at least five times and were reversible. We then examined the consequences of the evolution of staminodes by quantifying how staminodes affect visitation rates. A population of Mentzelia multiflora was used in an experimental study in which visitation of control flowers (staminodes present) was compared to that of treatment flowers (staminodes removed). The only pollinator was Apis mellifera (Apidae), which hovered above and landed on control flowers significantly more often than treatment flowers. Despite the preference for landing on staminodial flowers, once landed, pollinators spent an equal time on control and treatment flowers. We hypothesize that the increased visitation of staminodial flowers probably offsets the loss of the reproductive function in stamens. [ABSTRACT FROM AUTHOR]

In Japanese honey bees Apis cerana japonica, infestations of the tracheal mite Acarapis woodi have spread rapidly over the mainland of Japan, causing damage and the collapse of colonies. Meanwhile, infestations by mites in Apis mellifera have hardly been observed in Japan. In this study, we assessed and compared the susceptibility of the two species, A. cerana and A. mellifera, using an inoculation assay. We found that migrating female mites entered the tracheae of more newly emerged bees in both species but more frequently in A. cerana than in A. mellifera. Hence, the higher susceptibility in A. cerana is proposed as a factor causing the explosive epidemic of tracheal mites in only A. cerana in Japan. Moreover, we compared grooming behaviors between the two bee species using an observation assay as a preliminary experiment, although the bees were not exposed to the presence of tracheal mites. From these observations, the frequency of autogrooming (self-grooming) on the thorax in A. cerana was lower than that in A. mellifera. The difference in susceptibility to the mite between these two species may be due to the difference in grooming behavior frequency. [ABSTRACT FROM AUTHOR]

Background: Varroa mites are widely considered the biggest honey bee health problem worldwide. Until recently, Varroa jacobsoni has been found to live and reproduce only in Asian honey bee (Apis cerana) colonies, while V. destructor successfully reproduces in both A. cerana and A. mellifera colonies. However, we have identified an island population of V. jacobsoni that is highly destructive to A. mellifera, the primary species used for pollination and honey production. The ability of these populations of mites to cross the host species boundary potentially represents an enormous threat to apiculture, and is presumably due to genetic variation that exists among populations of V. jacobsoni that influences gene expression and reproductive status. In this work, we investigate differences in gene expression between populations of V. jacobsoni reproducing on A. cerana and those either reproducing or not capable of reproducing on A. mellifera, in order to gain insight into differences that allow V. jacobsoni to overcome its normal species tropism. Results: We sequenced and assembled a de novo transcriptome of V. jacobsoni. We also performed a differential gene expression analysis contrasting biological replicates of V. jacobsoni populations that differ in their ability to reproduce on A. mellifera. Using the edgeR, EBSeq and DESeq R packages for differential gene expression analysis, we found 287 differentially expressed genes (FDR ≤ 0.05), of which 91% were up regulated in mites reproducing on A. mellifera. In addition, mites found reproducing on A. mellifera showed substantially more variation in expression among replicates. We searched for orthologous genes in public databases and were able to associate 100 of these 287 differentially expressed genes with a functional description. Conclusions: There is differential gene expression between the two mite groups, with more variation in gene expression among mites that were able to reproduce on A. mellifera. A small set of genes showed reduced expression in mites on the A. mellifera host, including putative transcription factors and digestive tract developmental genes. The vast majority of differentially expressed genes were up-regulated in this host. This gene set showed enrichment for genes associated with mitochondrial respiratory function and apoptosis, suggesting that mites on this host may be experiencing higher stress, and may be less optimally adapted to parasitize it. Some genes involved in reproduction and oogenesis were also overexpressed, which should be further studied in regards to this host shift. [ABSTRACT FROM AUTHOR]

Premise of the study: According to Cope's 'law of the unspecialized' highly dependent species interactions are 'evolutionary dead ends,' prone to extinction because reversion to more generalist interactions is thought to be unlikely. Cases of extreme specialization, such as those seen between obligate mutualists, are cast as evolutionarily inescapable, inevitably leading to extinction rather than diversification of participating species. The pollination mutualism between Yucca plants and yucca moths (Tegeticula and Parategeticula) would seem to be locked into such an obligate mutualism. Yucca aloifolia populations, however, can produce large numbers of fruit lacking moth oviposition scars. Here, we investigate the pollination ecology of Y. aloifolia, in search of the non-moth pollination of a Yucca species. • Methods: We perform pollinator exclusion studies on Yucca aloifolia and a sympatric yucca species, Y. filamentosa. We then perform postvisit exclusion treatments, an analysis of dissected fruits, and a fluorescent dye transfer experiment. • Key results: As expected, Yucca filamentosa plants set fruit only when inflorescences were exposed to crepuscular and nocturnal pollinating yucca moths. In contrast, good fruit set was observed when pollinators were excluded from Y. aloifolia inflorescences from dusk to dawn, and nofruit set was observed when pollinators were excluded during the day. Follow up experiments indicated that European honeybees (Apis mellifera) were passively yet effectively pollinating Y. aloifolia flowers. • Conclusions: These results indicate that even highly specialized mutualisms may not be entirely obligate interactions or evolutionary dead ends. [ABSTRACT FROM AUTHOR]