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Letteratura scientifica selezionata sul tema "Bee pollen"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 20 febbraio 2023

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Articoli di riviste sul tema "Bee pollen"

Anis, Ulfah, Devi Silsia e Rizky Nirmala Kusumaningtyas. "Pengaruh Variasi Pollen Terhadap Karakteristik Kimia Bee pollen". Jurnal Teknologi Agro-Industri 8, n. 2 (23 dicembre 2021): 111–24. http://dx.doi.org/10.34128/jtai.v8i2.143.

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Bee pollen contains high enough nutrition. Bee pollen contains some nutrients such as water, ash, lipid, protein, natural antioxidants, palmitic acid, oleic acid, linoleic acid, and linolenic acid. The high nutrients on bee pollen causes bee pollen to be widely used by many people as a food additive on some food productions. Bee pollen is widely used as a fortificant and substitute material. Bee pollen as a substitute material on the making of crackers. On snack bar making, bee pollen is used as a fortificant material. Bee pollen as a fortificant is also used on the making of milk to increase its nutrients, especially the polyphenols. One of the factors effecting the nutrient contents of bee pollen is the source of pollen. There are two sources of pollens, multiflora and uniflora. The aim of this experiment is to know the effect of pollen sources on water, ash, lipid, protein and crude fiber content in 3 types of commercial pollen in Indonesia. The result is bee pollen from 3 different plants pollen have a significant difference to proximate content including water, ash, lipid, protein, carbohydrate, and crude fiber. Keywords: bee pollen, proximate, pollen

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Chang, Hongcai, Guiling Ding, Guangqun Jia, Mao Feng e Jiaxing Huang. "Hemolymph Metabolism Analysis of Honey Bee (Apis mellifera L.) Response to Different Bee Pollens". Insects 14, n. 1 (30 dicembre 2022): 37. http://dx.doi.org/10.3390/insects14010037.

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Pollen is essential to the development of honey bees. The nutrients in bee pollen vary greatly among plant species. Here, we analyzed the differences in the amino acid compositions of pear (Pyrus bretschneideri), rape (Brassica napus), and apricot (Armeniaca sibirica) pollens and investigated the variation in hemolymph metabolites and metabolic pathways through untargeted metabolomics in caged adult bees at days 7 and 14. The results showed that the levels of five essential amino acids (isoleucine, phenylalanine, lysine, methionine, and histidine) were the highest in pear pollen, and the levels of four amino acids (isoleucine: 50.75 ± 1.93 mg/kg, phenylalanine: 87.25 ± 2.66 mg/kg, methionine: 16.00 ± 0.71 mg/kg and histidine: 647.50 ± 24.80 mg/kg) were significantly higher in pear pollen than in the other two kinds of bee pollen (p < 0.05). The number of metabolites in bee hemolymph on day 14 (615) was significantly lower than that on day 7 (1466). The key metabolic pathways of bees, namely, “sphingolipid metabolism (p = 0.0091)”, “tryptophan metabolism (p = 0.0245)”, and “cysteine and methionine metabolism (p = 0.0277)”, were significantly affected on day 7. There was no meaningful pathway enrichment on day 14. In conclusion, pear pollen had higher nutritional value among the three bee pollens in terms of amino acid level, followed by rape and apricot pollen, and the difference in amino acid composition among bee pollens was reflected in the lipid and amino acid metabolism pathways of early adult honey bee hemolymph. This study provides new insights into the physiological and metabolic functions of different bee pollens in bees.

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Bleha, Roman, Tatiana Shevtsova, Andrej Sinica, Vojtech Kruzik e Jan Brindza. "Morphology, physicochemical properties and antioxidant capacity of bee pollens". Czech Journal of Food Sciences 37, No. 1 (6 marzo 2019): 1–8. http://dx.doi.org/10.17221/139/2018-cjfs.

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Six supposedly unifloral bee pollens of various botanical origins were characterised by morphometry, SEM, CIE L*a*b* colour parameters and FTIR spectroscopy. Botanical origin and homogeneity of bee pollens were verified by colour and morphology of pollen grains. Water activity, moisture and antioxidant capacity of bee pollens were also evaluated. The results were discussed in terms of connection between botanical origin, composition and antioxidant properties of pollen materials.

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Mosić, Mirjana, Jelena Trifković, Irena Vovk, Uroš Gašić, Živoslav Tešić, Branko Šikoparija e Dušanka Milojković-Opsenica. "Phenolic Composition Influences the Health-Promoting Potential of Bee-Pollen". Biomolecules 9, n. 12 (26 novembre 2019): 783. http://dx.doi.org/10.3390/biom9120783.

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Information on compositional, nutritional and functional properties of bee-pollen, as a health-promoting food, is essential for defining its quality. Concerning the nutritional importance of phenolic compounds, the aim of this study was to determine the phenolic profile and antioxidant activity of twenty-four bee-pollen samples collected from different regions of Serbia. High-performance thin-layer chromatographic (HPTLC) fingerprinting was used for profiling of bee-pollen samples according to the botanical type. HPTLC hyphenated with image analysis and a pattern recognition technique confirmed the grouping of samples caused by the specific phenolic composition of pollens of different botanical origin. Flavonoid glycosides in bee-pollen samples were identified by applying ultra-high-performance liquid chromatography (UHPLC) coupled with linear ion trap-Orbitrap mass spectrometry (LTQ Orbitrap MS). Eight out of twenty-seven flavonol glycosides were identified in bee-pollen samples for the first time. All analyzed bee-pollen samples showed a high number of phenolic compounds which may have therapeutic potential.

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Somerville, D. C., e H. I. Nicol. "Crude protein and amino acid composition of honey bee-collected pollen pellets from south-east Australia and a note on laboratory disparity". Australian Journal of Experimental Agriculture 46, n. 1 (2006): 141. http://dx.doi.org/10.1071/ea03188.

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Pollen pellets collected from honey bees foraging at 62 floral species were analysed for protein and amino acid content and their value for honey bee nutrition was determined. The crude protein levels of all pollen pellets analysed ranged from 9.2% for Hypochoeris radicata (flatweed) to 37.4% for Echium plantagineum (Paterson’s curse) with a mean of 25.9%. Pollen pellets from 15 species were identified as providing protein levels below those acknowledged to satisfy honey bee dietary requirements when they are the only source of pollen available to the honey bee colony. Pollens collected from species of the same genus demonstrated similar protein profiles. Isoleucine was deficient in 38% of the pollens with 69% of eucalypts and related species demonstrating a significant isoleucine deficiency.

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Pande, Rachna, e V. K. Verma. "Performance of hymenopteran insects as pollinators of pumpkin in Meghalaya". Journal of Applied and Natural Science 8, n. 4 (1 dicembre 2016): 1806–10. http://dx.doi.org/10.31018/jans.v8i4.1044.

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Pumpkin is a major cultivated crop particularly in north eastern states of India that depends on insects for the pollination, as the pollens of these plants are large sized and sticky. In the present study, field and lab experiments were conducted to determine the efficiency of the pollinators of pumpkin based on their diversity, relativeabundance and foraging activity. Total four hymenopteran insect pollinators were observed in field viz., bumble bee, little honey bee, Indian honey bee and Digger bee. On the basis of abundance and relative abundance bumble bee was identified as most abundant pollinator of pumpkin with 69.69 per cent mean relative abundance as other pollinators mean relative abundance was less than 25 per cent and it was only 3.49 per cent for Indian honey bee. Foraging speed and foraging rate of bumble bee was 7.13 sec/flower and foraging rate was 3.80 flower/minute. To ensure the efficient pollinator of pumpkin flower, pollen carrying capacity, pollen deposition and percent deposition of viable pollen was studied for all the pollinators in field and laboratory condition. The pollen carrying capacity of pollinators ranged from more than 7 mg to 1 mg. It was highest for bumble bee which was 7.33 mg followed by little honey bee (6.66 mg) and least pollen carrying capacity was observed in Digger bee (1.67 mg). Pollen depositions by pollinators on stigma in a single visit was again highest for bumble bee (565 pollen grains) with maximum number of viable pollen deposition 224.33 pollen grains out of which 39.7 per cent pollen was viable. So on the basis of above result it can be concluded that bumble bee was the most abundant and most efficient pollinator of pumpkin.

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Oroian, Mircea, Florina Dranca e Florin Ursachi. "Characterization of Romanian Bee Pollen—An Important Nutritional Source". Foods 11, n. 17 (30 agosto 2022): 2633. http://dx.doi.org/10.3390/foods11172633.

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Bee pollen represents an important bee product, which is produced by mixing flower pollens with nectar honey and bee’s salivary substances. It represents an important source of phenolic compounds which can have great importance for importance for prophylaxis of diseases, particularly to prevent cardiovascular and neurodegenerative disorders, those having direct correlation with oxidative damage. The aim of this study was to characterize 24 bee pollen samples in terms of physicochemical parameters, organic acids, total phenolic content, total flavonoid content, individual phenolics compounds, fatty acids, and amino acids from the Nort East region of Romania, which have not been studied until now. The bee pollen can be considered as a high protein source (the mean concentration was 22.31% d.m.) with a high energy value (390.66 kcal/100 g). The total phenolic content ranged between 4.64 and 17.93 mg GAE/g, while the total flavonoid content ranged between 4.90 and 20.45 mg QE/g. The high protein content was observed in Robinia pseudoacacia, the high content of lipids was observed in Robinia pseudoacacia pollen, the high fructose content in Prunus spp. pollen while the high F/G ratio was observed in Pinaceae spp. pollen. The high TPC was observed in Prunus spp. pollen, the high TFC was observed in Robinia pseudoacacia pollen, the high free amino acid content was observed in Pinaceae spp. pollen, and the high content of PUFA was reported in Taraxacum spp. pollen. A total of 16 amino acids (eight essential and eight non-essential amino acids) were quantified in the bee pollen samples analyzed. The total content of the amino acids determined for the bee pollen samples varied between 11.31 µg/mg and 45.99 µg/mg. Our results can indicate that the bee pollen is a rich source of protein, fatty acids, amino acids and bioactive compounds.

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Mishchenko, O., O. Lytvynenko, K. Afara e D. Kryvoruchko. "Тhe influence of the removal bee pollen with the pollen catcher on the flight activity and behaviour of the bees-polen collectors". Tehnologìâ virobnictva ì pererobki produktìv tvarinnictva, n. 1(164) (25 maggio 2021): 25–33. http://dx.doi.org/10.33245/2310-9289-2021-164-1-25-33.

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The possibility of demonstration of the productivity potential of the bee families depends directly on the level of provision of protein feed. In this regard, the study of the bees behavior that is connected to harvesting and processing of protein food is important for both biology and practical beekeeping. The presented work provides some data of experimental studies of the influence of the removal of the bee pollen on the flight activity of bees. The study of the ethological features that enhance the increase of collection, harvesting and processing of the protein feed was conducted. With this purpose the studies were conducted to elucidate the factors that induce collection of the protein feed -bee pollen by bees and its harvesting in the nest of the bee family in the form of the bee bread. The factors that influence the increase of the collection of the protein feed by bees were researched on experimental and control bee families- analogues. Throughout the studies it was identified that the bees with medium strength were the most active in collecting the pollen. The removal of the bee pollen with pollen catchers decreases the raising of brood by bee families, but doesn’t result in their significant weakening. With the enlargement of the area of the open brood the collection of the pollen by bees increases. In order to obtain the saleable bee pollen the strong bee families should be kept on the apiary. The bees-collectors of the protein feed have the individual features of collecting the bee pollen. With the removal of thbrood from the nest the activity the bees that flew out decreased. When adding the open brood the activity increased. On the contrary, with supply of the bee pollen to the nest, the pollen collecting activity decreases and adding the carbohydrates has no effect. The removal of the bee pollen with the pollen catcher from the bee families increases the flight activity which in turn leads to obtaining more bee pollen on the apiaries and pollination of additional quantity of entomophilous plants. In order to obtain the saleable bee pollen the strong families should be kept on the apiary and the removal should be conducted in the morning and day hours. Key words: bee family, Ukrainian steppe breed, pollen, bee pollen, bee bread, pollen catcher, flight activity of bees.

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Isik, Ayla, Murat Ozdemir e Ibrahim Doymaz. "Infrared drying of bee pollen: effects and impacts on food components". Czech Journal of Food Sciences 37, No. 1 (6 marzo 2019): 69–74. http://dx.doi.org/10.17221/410/2017-cjfs.

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Infrared radiation drying being one of the innovative drying methods was chosen to perform comparative study at different infrared power levels at 50, 62, 74 and 88 W. Quality attributes such as protein, fat, ash, carbohydrate, vitamin C content, solubility index and colour of infrared dried bee pollen samples were evaluated. The infrared power has a significant effect on the drying and quality characteristics especially colour. Drying time was reduced from 170 to 50 min when the infrared power level increased from 50 W to 88 W. Morphological changes on the surface of bee pollen grains increased with increasing the infrared power. The bee pollen infrared dried at 50 W retained its quality characteristics better than the bee pollens infrared dried at other power levels.

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Gabriele, Morena, Stefania Frassinetti e Laura Pucci. "Antimicrobial Activity and Nutraceutical Potential of Tuscan Bee-Pollens on Oxidative and Endoplasmic Reticulum Stress in Different Cell-Based Models". Proceedings 70, n. 1 (10 novembre 2020): 108. http://dx.doi.org/10.3390/foods_2020-07749.

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Bee-pollen is an apiary product of great interest owing to its high nutritional and therapeutic properties. This study aimed to assess the cellular antioxidant activity and the antihemolytic effects of Castanea, Rubus, and Cistus bee-pollens on oxidized human erythrocytes. In addition, the antimicrobial potential of each sample was tested on three Gram-negative and two Gram-positive bacteria. Finally, the effect of Castanea bee-pollen, showing better phytochemical content, was analyzed on human microvascular endothelial cells (HMEC-1) exposed to thapsigargin, used to induce endoplasmic reticulum stress (ER-stress). Our results showed good biological activities of all bee-pollen samples, which, under oxidative conditions, significantly improved the erythrocytes’ antioxidant activity and limited cell lyses. Moreover, all samples exerted antimicrobial activity with different selectivity among the tested microorganisms, with minimal inhibitory concentration values ranging from 5 to 10 mg/mL. Finally, thapsigargin treatment increased intracellular ROS (reactive oxygen species) production and up-regulated the expression of factors involved in the ER-stress and inflammatory pathways. Conversely, Castanea bee-pollen was effective in reducing gene overexpression, as well as the oxidation process arising from thapsigargin treatment, with a maximum protective effect at 10 µg/mL. In conclusion, bee-pollens, mainly Castanea species, represent good natural antibacterial and potential nutraceutical products useful in the prevention of free radical and ER-stress associated diseases.

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Più fonti

Tesi sul tema "Bee pollen"

Kitaoka, Traci Kimiko. "Bumble bee pollen foraging activation role of colony stores and pollen quality and odor /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p1453656.

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Thesis (M.S.)--University of California, San Diego, 2008.
Title from first page of PDF file (viewed July 25, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 28-29).

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Russell, Avery L., e Daniel R. Papaj. "Artificial pollen dispensing flowers and feeders for bee behaviour experiments". Enviroquest Ltd, 2016. http://hdl.handle.net/10150/621206.

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The study of foraging behaviour in plant-pollinator mutualisms has benefitted from the use of artificial flowers to manipulate floral display traits and the delivery of floral rewards. The two most common floral rewards are pollen and nectar; some pollinators, such as bees, are obliged to collect both for survival and reproduction. While flexible designs for artificial flowers providing nectar rewards abound, useful designs for artificial flowers that dispense pollen are few. This disparity mirrors a heavy emphasis on nectar collection in the study of pollinator foraging behaviour. In this study we describe a novel, easily constructed and modifiable artificial flower that dispenses flexible amounts of pollen via an ‘anther’ composed of a chenille stem. Using controlled lab assays, we show that more pulverized honeybee pollen is collected by bumblebee (Bombus impatiens) workers at chenille stem feeders than at dish-type feeders. We suggest that the paucity of studies examining pollinator cognition in the context of pollen rewards might be partly remedied if researchers had access to inexpensive and easily adjustable pollen-offering surrogate flowers.

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Osborne, Juliet Laura. "Evaluating a pollination system : Borago officinalis and bees". Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.360935.

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Richardson, Rodney Trey. "Molecular analysis of honey bee foraging ecology". The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1543239052414523.

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Andersson, Albin. "A novel chitosan-stearic coating with bee-pollen microcapsules for corrosion protection". Thesis, KTH, Materialvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-277886.

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In this project a novel chitosan-stearic acid (CS-SA) coating with bee-pollen microcapsules for encapsulation of 2-mecraptobenzothiazole (MBT) as a waterborne formulation for a biocompatible corrosion protection coating was developed and the coating properties was analyzed. Hydrophobic stearic acid (SA) was crosslinked with via a carbodiimide reaction to form micelles and is assembled on the bee- pollen grains and the chitosan matrix was further self-crosslinked using glutaraldehyde (GA). Stearic acid was used to hydrophobically interact with modified pollen and with further crosslinking with the chitosan, which was proven successful by FTIR results. The encapsulation of anticorrosive agent MBT into pollen was successful and examined by UV-Vis spectroscopy, however, the pollen cannot form a fully stable formulation with the chitosan micelle matrix, partially due to its relatively big size (ca. 20 μm), causing problems with forming a proper barrier protection. The size of the grains and the interference of the carbodiimide crosslinking is the most severe problems with the pollen microcapsules. Therefore, no further testing of the corrosive properties could be done, which requires a dense and stable coating to sustain in salty water for the whole measurement period. As the reference coatings without pollen provided much more promising results, especially when crosslinked with GA, the conclusion is that the reactivity of the pollen is proven difficult to crosslink, and choosing a proper size of a microcontainer and the appropriate encapsulation method in the binder matrix is vital and important for developing a corrosion protective coating.
Detta projekt bygger på framställningen och analysen av en tidigare outforskad chitosan-stearinsyra (CS-SA) färg med bi pollen som mikrokapslar för inkapsling av 2-mercaptobenzothiazole (MBT) som en vattenlöslig och biokompatibel anti-korrosions färg. CS-SA var tillverkat med en carbodiimide reaktion för att bilda miceller som ska omslutna pollenkornen, och även ett försök med vidare tvärbindning mellan chitosanen med glutaraldehyde (GA) gjordes. Stearinsyra fick interagera hydrofobiskt med den modifierade pollen och tvärbindes sedan med chitosan, som visade sig vara lyckad med hjälp av FTIR analys. Enkapsuleringen av MBT visade sig med UV-Vis spektroskopi vara lyckad, dock på grund av pollens stora korn (ca 20 μm) orsakade problem med att bilda en stabil barriär mot omgivningen. Storleken av pollen och dess reaktivitet med carbodiimide tvärbindningen är de mest allvarliga problemen med pollen som mikrokapslar, och därav gjordes inga vidare tester av korrosions egenskaperna då detta kräver en täckande och stabil film genom hela mätningen. Då även referensfärgen som gjordes utan pollen gav avsevärt mycket bättre resultat i det avseendet är slutsatsen att reaktiviteten av pollen gör det problematiskt att tvärbinda med chitosan och valet av en kapsel av rätt storlek och hur den inkapslar är avgörande för att utveckla en bra korrosionsskyddande färg.

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Peters, Lizette Alice. "Effect of pollen diet and honey bee (apis mellifera l.) primer pheromones on worker bee food producing glands". [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3167.

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Russell, Avery L., Rebekah E. Golden, Anne S. Leonard e Daniel R. Papaj. "Bees learn preferences for plant species that offer only pollen as a reward". Oxford University Press, 2016. http://hdl.handle.net/10150/621207.

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The astonishing diversity of floral form in angiosperm plants is driven in large part by preferences of pollinators for various floral traits, including learned preferences. Remarkably, almost all of a vast literature on learning and memory in pollinators relates to nectar as a reward, even though bees and many flies, beetles, and butterflies must collect pollen. In this study, we asked if bees formed preferences for plant species from which pollen had been collected successfully. Using absolute conditioning, we gave pollen foraging bees experience with plant species that offered only pollen rewards. Naive bees generally showed modest preferences, whereas experienced bees adopted strong preferences for those species over alternative species not previously experienced. Learned preferences were retained for at least 24 h, consistent with preferences learned with nectar rewards. These experience-mediated changes in preference raised the possibility that bees formed associations between particular floral features and pollen rewards. We therefore asked if learned preferences required that bees successfully collect pollen. Using differential conditioning, we determined that learned preferences were strongly influenced by receipt of a pollen reward. In a final experiment, we characterized the importance of 2 floral features, the corolla and the anther, in the expression of learned preferences. Although experience altered responses to both floral parts, responses to anthers were influenced more strongly. We discuss recent evidence in the literature for associative learning with pollen rewards and propose that learned preferences in the context of pollen collection have played an important role in floral display evolution.

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Mach, Bernadette Maria. "BEE CONSERVATION IN URBAN LANDSCAPES: ASSESSING BEE ASSEMBLAGES, BEE–ATTRACTIVENESS, AND NUTRITRITIONAL VALUE OF WOODY LANDSCAPE PLANTS AND MITIGATING POTENTIAL BEE HAZARD FROM NEONICOTINOID INSECTICIDES". UKnowledge, 2018. https://uknowledge.uky.edu/entomology_etds/46.

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Public awareness of declining pollinator populations has increased interest in creating “bee–friendly” urban landscapes. I quantified bee visitation and assemblages of 72 species of flowering woody plants common in urban landscapes. I found strong plant species effects and variation in seasonal activity of particular bee taxa but no overall differences in bee visitation or genus diversity between native versus nonnative species or trees versus shrubs. Analysis of pollen from a subset of these plants revealed small but statistically significant differences in total and essential amino acids between native and nonnative species and trees and shrubs, although each group had species with high quality pollen. Uptake and dissipation of soil–applied imidacloprid and dinotefuran was measured in nectar and leaves of two woody plant species, Ilex × attenuata and Clethra alnifolia to assess concentrations to which pollinators might be exposed in landscape settings. Three application timings were evaluated. Residues in nectar and tissue were analyzed by HPLC–MS/MS in two successive years. Residues in nectar following autumn or spring applications exceed concentrations shown to adversely affect individual and colony–level traits of bees. Summer application mitigated concentrations of imidacloprid (8–31 ng/g), but not dinotefuran (235–1191 ng/g), in nectar.

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PAPA, GIULIA. "Study of airborne particulate matter (PM) contaminating the honey bee Apis mellifera Linnaeus, 1758 and bee products". Doctoral thesis, Università Cattolica del Sacro Cuore, 2021. http://hdl.handle.net/10280/94210.

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Apis mellifera Linnaeus (1758) è un insetto eusociale conosciuto in tutto il mondo sia per la produzione di miele sia per il suo ruolo di impollinatore, uno dei servizi ecosistemici fondamentali per la biodiversità del pianeta. Durante la sua attività di foraggiamento, l’ape è esposta agli inquinanti ambientali tra cui il particolato atmosferico aerodisperso (PM). Il particolato atmosferico può depositarsi sul corpo dell’insetto e infine contaminare anche i prodotti apistici come polline e miele. Il PM può avere diverse dimensioni (es. PM10, PM2.5, PM0.1), composizione chimica, morfologia e fonti di emissione (naturale o antropica). Nel presente elaborato di tesi, tecniche di microscopia elettronica a scansione (SEM-EDX) sono state utilizzate per caratterizzare la contaminazione da PM di origine antropica del corpo dell’ape e dei suoi prodotti (Capitolo 2 e Capitolo 3) e analisi molecolari per studiare gli eventuali effetti sub-letali sul microbiota intestinale di api esposte ai PM per via orale (Capitolo 4).
Apis mellifera Linnaeus (1758) order Hymenoptera family Apidae, is a eusocial insect widely known for its role in pollination, a fundamental ecosystem service for plant biodiversity and ultimately for the planet. During flight and foraging activity, the honey bee can collect airborne particulate matter (PM) on their own body, especially on the forewings, and can also contaminate bee products as pollen and honey. Particulate matter can originate from natural or anthropic sources, and is characterised by size (e.g., PM10, PM2.5, PM0.1), chemical composition, and morphology. In this thesis, honey bee, pollen and honey were used as bioindicator of PM – from coarse to ultrafine – in industrial areas of the Po Valley, Italy (Chapter 2 and Chapter 3). The (sub-lethal) effects of Titanium dioxide – a widespread airborne PM1 pollutant – on the honey bee through oral exposure was then investigated (Chapter 4). The technique used to analyse the PM contaminating bees and bee products is the scanning electron microscopy (SEM) coupled with X-ray spectrometer (EDX). EDX spectra allowed us to obtain chemical information from specimens, while backscattered-electron (BSE) imaging and elemental mapping provided both compositional and topographic information of PM.

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Larsson, Magnus. "To Bee or Not to Be : Critical Floral Resources of Wild-Bees". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Universitetsbiblioteket [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7108.

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Più fonti

Libri sul tema "Bee pollen"

Larkin, Tim. Bee pollen as a health food. Rockville, Md: Dept. of Health and Human Services, Public Health Service, Food and Drug Administration, 1985.

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Larkin, Tim. Bee pollen as a health food. Rockville, Md: Dept. of Health and Human Services, Public Health Service, Food and Drug Administration, 1985.

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Jensen, Bernard. Bee well--bee wise: With bee pollen, propolis, and royal jelly. Escondido, CA, USA: B. Jensen, 1994.

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Vit, Patricia, Silvia R. M. Pedro e David W. Roubik, a cura di. Pot-Pollen in Stingless Bee Melittology. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-61839-5.

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Jian kang de shou hu shen: Hua fen de liao xiao. Taibei Xian Xindian Shi: Shi mao chu ban she, 1998.

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Wade, Carlson. Health from the hive: Honey, bee pollen, bee propolis, royal jelly. New Canaan, Conn: Keats Pub., 1992.

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Brown, Royden. How to live the millennium: The bee pollen bible. 2^a ed. Prescott, AZ: Hohm Press, 1989.

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Med, propolis, perga i drugie produkty pchelovodstva ot vsekh bolezneĭ. Moskva: Ripol klassik, 2011.

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(Illustrator), Jack Tickle, a cura di. The Very Greedy Bee. Wilton, CT: Tiger Tales, 2007.

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Health and healing with bee products: Boost health, treat conditions and prevent disease with bee pollen, propolis, honey, royal jelly. Summertown, Tenn: Alive Books, 2007.

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Capitoli di libri sul tema "Bee pollen"

Campos, M. G., A. Cunha e K. R. Markham. "Bee-Pollen". In Bee Products, 93–100. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4757-9371-0_12.

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Dicklow, M. B., R. D. Firman, D. B. Rupert, K. L. Smith e T. E. Ferrari. "Controlled Enpollination of Honeybees (Apis mellifera): Bee-to-Bee and Bee-to-Tree Pollen Transfer". In Biotechnology and Ecology of Pollen, 449–54. New York, NY: Springer New York, 1986. http://dx.doi.org/10.1007/978-1-4613-8622-3_72.

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De-Melo, Adriane Alexandre Machado, e Ligia Bicudo de Almeida-Muradian. "Chemical Composition of Bee Pollen". In Bee Products - Chemical and Biological Properties, 221–59. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-59689-1_11.

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Vit, Patricia, Giancarlo Ricciardelli D’Albore, Ortrud Monika Barth, María Peña-Vera e Elizabeth Pérez-Pérez. "Characterization of Pot-Pollen from Southern Venezuela". In Pot-Pollen in Stingless Bee Melittology, 361–75. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-61839-5_26.

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Roubik, David W., e Jorge Enrique Moreno Patiño. "Pot-Pollen as a Discipline: What Does It Include?" In Pot-Pollen in Stingless Bee Melittology, 3–15. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-61839-5_1.

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Di Trani, Juan Carlos, e Rogel Villanueva-Gutiérrez. "Annual Foraging Patterns of the Maya Bee Melipona beecheii (Bennett, 1831) in Quintana Roo, Mexico". In Pot-Pollen in Stingless Bee Melittology, 131–38. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-61839-5_10.

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Meléndez Ramírez, Virginia, Ricardo Ayala e Hugo Delfín González. "Crop Pollination by Stingless Bees". In Pot-Pollen in Stingless Bee Melittology, 139–53. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-61839-5_11.

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Vossler, Favio Gerardo, Diego César Blettler, Guillermina Andrea Fagúndez e Milagros Dalmazzo. "Stingless Bees as Potential Pollinators in Agroecosystems in Argentina: Inferences from Pot-Pollen Studies in Natural Environments". In Pot-Pollen in Stingless Bee Melittology, 155–75. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-61839-5_12.

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Fabre Anguilet, Edgard Cédric, Taofic Alabi, Bach Kim Nguyen, Toussaint Ndong Bengone, Éric Haubruge e Frédéric Francis. "Stingless Bees (Hymenoptera, Apoidea, Meliponini) from Gabon". In Pot-Pollen in Stingless Bee Melittology, 179–88. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-61839-5_13.

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Roubik, David W. "100 Species of Meliponines (Apidae: Meliponini) in a Parcel of Western Amazonian Forest at Yasuní Biosphere Reserve, Ecuador". In Pot-Pollen in Stingless Bee Melittology, 189–206. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-61839-5_14.

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Atti di convegni sul tema "Bee pollen"

Xue, Yingen. "Neonicotinoid residues in fresh corn pollen and proportion of corn pollen in bee-collected pollen during corn pollination". In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.115318.

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Zhang, Jiewei, e Zeyuan Huang. "Preparation of a Kind of Bee pollen Effervescent Tablets". In 2nd International Conference on Science and Social Research (ICSSR 2013). Paris, France: Atlantis Press, 2013. http://dx.doi.org/10.2991/icssr-13.2013.69.

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Diaz Guzman, Sonia, Devon Henspeter, Megan Taylor e Shawn Duan. "Drone Pollination of Flowering Vegetation for Agricultural Applications". In ASME 2021 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/imece2021-70545.

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Abstract With an ever-changing climate, the decline in the bee population is forcing humans to find supplemental ways to pollinate. A mechanical substitute for a bee needs to be as efficient or better than bee pollination since it will require one person to do the work of many bees. Pollinating one flower at a time would be too time consuming to be effective, so a drone mounted pollen distribution device is the best direction to go to solve this problem. This is a game changing design to prevent a lack of food-producing plant growth as the bee population decreases over time. The design is a low-cost alternative that can be adjusted to meet the consumer needs based on the type of pollination. This design is easy to manufacture en masse due to its simplicity. The design and operation have been optimized using stress, torque, and safety factor analyses to ensure that the product can withstand the loads applied during operation. This drone pollinator will have the ability to work for various drone types and plant pollens. With the use of commercial drones, the ability to distribute pollen to a large orchard or forested area will allow humans to supplement bee pollination on a large scale in the farming and forest conservation industries.

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B. Balderas, Marilyn. "POLLEN SPECTRUM AND PHENOLOGY OF STINGLESS BEE (Tetragonula biroi Friese) PLANTS". In International Conference on Fisheries and Aquaculture. TIIKM, 2016. http://dx.doi.org/10.17501/icoaf.2016.2111.

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Sledevic, Tomyslav. "The Application of Convolutional Neural Network for Pollen Bearing Bee Classification". In 2018 IEEE 6th Workshop on Advances in Information, Electronic and Electrical Engineering (AIEEE). IEEE, 2018. http://dx.doi.org/10.1109/aieee.2018.8592464.

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Pyeon, HI, J. Bak, JI Seok e YS Choi. "Therapeutic application of wet-ground bee pollen in benign prostatic hyperplasia". In GA 2017 – Book of Abstracts. Georg Thieme Verlag KG, 2017. http://dx.doi.org/10.1055/s-0037-1608470.

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LUIZ, A. C., A. A. ARRUDA, K. A. MOREIRA, D. A. Viana MARQUES, A. L. F. PORTO e C. A. LIMA. "COLLAGENASE PRODUCTION BY YEAST (13II) ISOLATED FROM BEE POLLEN (Melípona spp.)". In XX Congresso Brasileiro de Engenharia Química. São Paulo: Editora Edgard Blücher, 2015. http://dx.doi.org/10.5151/chemeng-cobeq2014-0132-26885-171626.

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Lupaescu, Ancuta-Veronica, Brindusa-Alina Petre, Monica Iavorschi e Mircea Oroian. "ANALYSIS OF PROTEIN CONTENT AND EVALUATION OF ANTIOXIDANT ACTIVITY OF LINDEN AND HAWTHORN POLLEN". In 22nd SGEM International Multidisciplinary Scientific GeoConference 2022. STEF92 Technology, 2022. http://dx.doi.org/10.5593/sgem2022/6.1/s25.08.

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Harvested bee pollen has been used since ancient times for its healthy properties and nutritional value. In terms of composition, bee pollen contains a large number of different substances such as proteins, carbohydrates and lipids as well as phenolic organic compounds. The protein content is the second most abundant component, its levels (10 to 40%, w/w) depending on the type of plant. Recently, numerous studies have demonstrated the beneficial properties of pollen in promoting health and reducing the risk of developing certain illnesses. In addition, the anti-oxidative and anti-aging effects have provided beneficial support for the development of bee pollen in the field of cosmetics. In this study, the effect of sonication treatment on the protein content of linden and hawthorn pollen was evaluated. Quantitative information regarding the protein content of sonicated extracts was determined by Bradford method while the antioxidant capacity of protein extract was evaluated using the DPPH free radical method. Furthermore, one dimensional electrophoresis and mass spectrometric analysis was used to acquire a more detailed description of pollen protein content.

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Mirjanić, Goran, Nebojša Nedić e Lejla Biber. "UTICAJ SEZONE I RAZLIČITE PRIHRANE ZIMSKIH PČELA NA POVRŠINU SAKUPLJENOG POLENA". In XXVII savetovanje o biotehnologiji. University of Kragujevac, Faculty of Agronomy, 2022. http://dx.doi.org/10.46793/sbt27.207m.

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The aim of this study was to determine the influence of the season and different types of bee feeding during the winter period on the surface of collected pollen in the hive. The smallest area (0.74 dm2) of collected pollen was determined in bee colonies fed with sugar acid invert syrup with the addition of brewer's yeast. The largest area of 1.39 dm2 was found in bee colonies fed with sugar enzyme invert syrup with the addition of brewer's yeast. The obtained research results indicate a highly significant influence of the beekeeping season and environmental factors on pollen yield in bee colonies. The influence of the type of bee feeding during the winter period has no statistically significant effect on the surface of collected pollen in the hive.

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Walton, Alexander Raymond. "Larval and adult pollen diets affect honey bee worker response to the queen". In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.115591.

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Rapporti di organizzazioni sul tema "Bee pollen"

Radev, Zheko. Sugars Composition of Bee-collected Pollen. "Prof. Marin Drinov" Publishing House of Bulgarian Academy of Sciences, dicembre 2021. http://dx.doi.org/10.7546/crabs.2021.11.03.

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Law, Edward, Samuel Gan-Mor, Hazel Wetzstein e Dan Eisikowitch. Electrostatic Processes Underlying Natural and Mechanized Transfer of Pollen. United States Department of Agriculture, maggio 1998. http://dx.doi.org/10.32747/1998.7613035.bard.

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The project objective was to more fully understand how the motion of pollen grains may be controlled by electrostatic forces, and to develop a reliable mechanized pollination system based upon sound electrostatic and aerodynamic principles. Theoretical and experimental analyses and computer simulation methods which investigated electrostatic aspects of natural pollen transfer by insects found that: a) actively flying honeybees accumulate ~ 23 pC average charge (93 pC max.) which elevates their bodies to ~ 47 V likely by triboelectrification, inducing ~ 10 fC of opposite charge onto nearby pollen grains, and overcoming their typically 0.3-3.9 nN detachment force resulting in non-contact electrostatic pollen transfer across a 5 mm or greater air gap from anther-to-bee, thus providing a theoretical basis for earlier experimental observations and "buzz pollination" events; b) charge-relaxation characteristics measured for flower structural components (viz., 3 ns and 25 ns time constants, respectively, for the stigma-style vs. waxy petal surfaces) ensure them to be electrically appropriate targets for electrodeposition of charged pollen grains but not differing sufficiently to facilitate electrodynamic focusing onto the stigma; c) conventional electrostatic focusing beneficially concentrates pollen-deposition electric fields onto the pistill tip by 3-fold as compared to that onto underlying flower structures; and d) pollen viability is adequately maintained following exposure to particulate charging/management fields exceeding 2 MV/m. Laboratory- and field-scale processes/prototype machines for electrostatic application of pollen were successfully developed to dispense pollen in both a dry-powder phase and in a liquid-carried phase utilizing corona, triboelectric, and induction particulate-charging methods; pollen-charge levels attained (~ 1-10 mC/kg) provide pollen-deposition forces 10-, 77-, and 100-fold greater than gravity, respectively, for such charged pollen grains subjected to a 1 kV/cm electric field. Lab and field evaluations have documented charged vs. ukncharged pollen deposition to be significantly (a = 0.01-0.05) increased by 3.9-5.6 times. Orchard trials showed initial fruit set on branches individually treated with electrostatically applied pollen to typically increase up to ~ 2-fold vs. uncharged pollen applications; however, whole-tree applications have not significantly shown similar levels of benefit and corrective measures continue. Project results thus contribute important basic knowledge and applied electrostatics technology which will provide agriculture with alternative/supplemental mechanized pollination systems as tranditional pollen-transfer vectors are further endangered by natural and man-fade factors.

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Hefetz, Abraham, e Justin O. Schmidt. Use of Bee-Borne Attractants for Pollination of Nonrewarding Flowers: Model System of Male-Sterile Tomato Flowers. United States Department of Agriculture, ottobre 2003. http://dx.doi.org/10.32747/2003.7586462.bard.

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The use of bee natural product for enhancing pollination is especially valuable in problematic crops that are generally avoided by bees. In the present research we attempted to enhance bee visitation to Male Sterile (M-S) tomato flowers generally used in the production of hybrid seeds. These flowers that lack both pollen and nectar are unattractive to bees that learn rapidly to avoid them. The specific objects were to elucidate the chemical composition of the exocrine products of two bumble bee species the North American Bombus impatiens and the Israeli B. terrestris. Of these, to isolate and identify a bee attractant which when sprayed on M-S tomato flowers will enhance bee visitation, and to provide a procedure of the pheromone application regime. During the research we realized that our knowledge of B. impatiens is too little and we narrowed the objective to learning the basic social behavior of the bees and the pattern of foraging in a flight chamber and how it is affected by biogenic amines. Colonies of B. impatiens are characterized by a high number of workers and a relatively small number of queens. Size differences between queens and workers are pronounced and the queen seems to have full control over egg laying. Only about 9% of the workers in mature colonies had mature oocytes, and there were no signs of a "competition phase" as we know in B. terrestris. Queens and workers differ in their exocrine bouquet. Queen's Dufour's gland possesses a series of linear, saturated and unsaturated hydrocarbons whereas that of workers contains in addition a series of wax-type esters. Bees were trained to either visit or avoid artificially scented electronic flowers in a flight chamber. Since bee also learned to avoid scented non-rewarding flowers we attempted to interfere with this learning. We tested the effect of octopamine, a biogenic amine affecting bee behavior, on the choice behavior of free-flying bumblebees. Our results show that octopamine had no significant effect on the bees' equilibrium choice or on the overall rate of the behavioral change in response to the change in reward. Rather, octopamine significantly affected the time interval between the change in reward status and the initiation of behavioral change in the bee. In B. terrestris we studied the foraging pattern of the bees on tomato flowers in a semi commercial greenhouse in Yad Mordechai. Bee learned very quickly to avoid the non- rewarding M-S flowers, irrespective of their arrangement in the plot, i.e., their mixing with normal, pollen bearing flowers. However, bees seem to "forget" this information during the night since the foraging pattern repeats itself the next morning. Several exocrine products were tested as visitation enhancers. Among these, tarsal gland extracts are the most attractive. The compounds identified in the tarsal gland extract are mostly linear saturated hydrocarbons with small amounts of unsaturated ones. Application was performed every second day on leaves in selected inflorescences. Bee visitation increased significantly in the treated inflorescences as compared to the control, solvent treated. Treatment of the anthers cone was more effective than on the flower petals or the surrounding leaves. Methanol proved to be a non-flower-destructive solvent. We have shown that bumble bees (B. terrestris) can be manipulated by bee-borne attractants to visit non-rewarding flowers. We have further demonstrated that the bees learning ability can be manipulated by applying exogenously octopamine. Both methods can be additively applied in enhancing pollination of desired crops. Such manipulation will be especially useful in tomato cultivation for hybrid seed production.

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Miller, Gad, e Jeffrey F. Harper. Pollen fertility and the role of ROS and Ca signaling in heat stress tolerance. United States Department of Agriculture, gennaio 2013. http://dx.doi.org/10.32747/2013.7598150.bard.

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The long-term goal of this research is to understand how pollen cope with stress, and identify genes that can be manipulated in crop plants to improve reproductive success during heat stress. The specific aims were to: 1) Compare heat stress dependent changes in gene expression between wild type pollen, and mutants in which pollen are heat sensitive (cngc16) or heat tolerant (apx2-1). 2) Compare cngc16 and apx2 mutants for differences in heat-stress triggered changes in ROS, cNMP, and Ca²⁺ transients. 3) Expand a mutant screen for pollen with increased or decreased thermo-tolerance. These aims were designed to provide novel and fundamental advances to our understanding of stress tolerance in pollen reproductive development, and enable research aimed at improving crop plants to be more productive under conditions of heat stress. Background: Each year crop yields are severely impacted by a variety of stress conditions, including heat, cold, drought, hypoxia, and salt. Reproductive development in flowering plants is highly sensitive to hot or cold temperatures, with even a single hot day or cold night sometimes being fatal to reproductive success. In many plants, pollen tube development and fertilization is often the weakest link. Current speculation about global climate change is that most agricultural regions will experience more extreme environmental fluctuations. With the human food supply largely dependent on seeds, it is critical that we consider ways to improve stress tolerance during fertilization. The heat stress response (HSR) has been intensively studied in vegetative tissues, but is poorly understood during reproductive development. A general paradigm is that HS is accompanied by increased production of reactive oxygen species (ROS) and induction of ROS-scavenging enzymes to protect cells from excess oxidative damage. The activation of the HSR has been linked to cytosolic Ca²⁺ signals, and transcriptional and translational responses, including the increased expression of heat shock proteins (HSPs) and antioxidative pathways. The focus of the proposed research was on two mutations, which have been discovered in a collaboration between the Harper and Miller labs, that either increase or decrease reproductive stress tolerance in a model plant, Arabidopsis thaliana (i.e., cngc16--cyclic nucleotide gated channel 16, apx2-1--ascorbate peroxidase 2,). Major conclusions, solutions, achievements. Using RNA-seq technology, the expression profiles of cngc16 and apx2 pollen grains were independently compared to wild type under favourable conditions and following HS. In comparison to a wild type HSR, there were 2,776 differences in the transcriptome response in cngc16 pollen, consistent with a model in which this heat-sensitive mutant fails to enact or maintain a normal wild-type HSR. In a comparison with apx2 pollen, there were 900 differences in the HSR. Some portion of these 900 differences might contribute to an improved HSR in apx2 pollen. Twenty-seven and 42 transcription factor changes, in cngc16 and apx2-1, respectively, were identified that could provide unique contributions to a pollen HSR. While we found that the functional HS-dependent reprogramming of the pollen transcriptome requires specific activity of CNGC16, we identified in apx2 specific activation of flavonol-biosynthesis pathway and auxin signalling that support a role in pollen thermotolerance. Results from this study have identified metabolic pathways and candidate genes of potential use in improving HS tolerance in pollen. Additionally, we developed new FACS-based methodology that can quantify the stress response for individual pollen in a high-throughput fashion. This technology is being adapted for biological screening of crop plant’s pollen to identify novel thermotolerance traits. Implications, both scientific and agricultural. This study has provided a reference data on the pollen HSR from a model plant, and supports a model that the HSR in pollen has many differences compared to vegetative cells. This provides an important foundation for understanding and improving the pollen HSR, and therefor contributes to the long-term goal of improving productivity in crop plants subjected to temperature stress conditions. A specific hypothesis that has emerged from this study is that pollen thermotolerance can be improved by increasing flavonol accumulation before or during a stress response. Efforts to test this hypothesis have been initiated, and if successful have the potential for application with major seed crops such as maize and rice.

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Arpaia, Mary Lu, Sharoni Shafir, Thomas Davenport e Arnon Dag. Enhancement of avocado pollination and productivity - an interdisciplinary approach. United States Department of Agriculture, gennaio 2007. http://dx.doi.org/10.32747/2007.7695882.bard.

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The original objective was to determine the impact of temperature on floral behavior and pollen tube growth and humidity on the proportions of self-, close, and cross-pollinated avocado fruit on trees growing in humid, coastal and dry, inland CA climates. Because self-pollination was demonstrated to be the prevailing mode of pollination in Florida cultivars in warm humid conditions, it was appropriate to determine if similar rates of self-pollination occur in a dry Mediterranean climate present in California. The conclusions of the work were that despite limiting cool temperatures present in Ventura County, where the research was conducted, self-pollination within Stage 2 flowers is the dominant mode of pollination at both the humid and dry sites. Moreover, it was determined that pollen transfer is mediated by wind and bees have a negligible role in pollen transfer. Temperatures that are marginally warm enough to allow somewhat normal floral opening and closing behavior are still insufficient to provide pollen tube growth to the ovule before abscission of the flower. These results provide the basis for understanding why growers utilizing solid block avocado plantings achieve good yields without bees.

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Eyal, Yoram, e Sheila McCormick. Molecular Mechanisms of Pollen-Pistil Interactions in Interspecific Crossing Barriers in the Tomato Family. United States Department of Agriculture, maggio 2000. http://dx.doi.org/10.32747/2000.7573076.bard.

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During the evolutionary process of speciation in plants, naturally occurring barriers to reproduction have developed that affect the transfer of genes within and between related species. These barriers can occur at several different levels beginning with pollination-barriers and ending with hybrid-breakdown. The interaction between pollen and pistils presents one of the major barriers to intra- and inter-specific crosses and is the focus of this research project. Our long-term goal in this research proposal was defined to resolve questions on recognition and communication during pollen-pistil interactions in the extended tomato family. In this context, this work was initiated and planned to study the potential involvement of tomato pollen-specific receptor-like kinases (RLK's) in the interaction between pollen and pistils. By special permission from BARD the objectives of this research were extended to include studies on pollen-pistil interactions and pollination barriers in horticultural crops with an emphasis on citrus. Functional characterization of 2 pollen-specific RLK's from tomato was carried out. The data shows that both encode functional kinases that were active as recombinant proteins. One of the kinases was shown to accumulate mainly after pollen germination and to be phosphorylated in-vitro in pollen membranes as well as in-vivo. The presence of style extract resulted in dephosphorylation of the RLK, although no species specificity was observed. This data implies a role for at least one RLK in pollination events following pollen germination. However, a transgenic plant analysis of the RLK's comprising overexpression, dominant-negative and anti-sense constructs failed to provide answers on their role in pollination. While genetic effects on some of the plants were observed in both the Israeli and American labs, no clear functional answers were obtained. An alternative approach to addressing function was pursued by screening for an artificial ligand for the receptor domain using a peptide phage display library. An enriched peptide sequence was obtained and will be used to design a peptide-ligand to be tested for its effect o pollen germination and tube growth. Self-incompatibility (SI) in citrus was studied on 3 varieties of pummelo. SI was observed using fluorescence microscopy in each of the 3 varieties and compatibility relations between varieties was determined. An initial screen for an S-RNase SI mechanism yielded only a cDNA homologous to the group of S-like RNases, suggesting that SI results from an as yet unknown mechanism. 2D gel electrophoresis was applied to compare pollen and style profiles of different compatibility groups. A "polymorphic" protein band from style extracts was observed, isolated and micro-sequenced. Degenerate primers designed based on the peptide sequence date will be used to isolate the relevant genes i order to study their potential involvement in SI. A study on SI in the apple cultivar Top red was initiated. SI was found, as previously shown, to be complete thus requiring a compatible pollinator variety. A new S-RNase allele was discovered fro Top red styles and was found to be highly homologous to pear S-RNases, suggesting that evolution of these genes pre-dated speciation into apples and pears but not to other Rosaceae species. The new allele provides molecular-genetic tools to determine potential pollinators for the variety Top red as well as a tool to break-down SI in this important variety.

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Firon, Nurit, Prem Chourey, Etan Pressman, Allen Hartwell e Kenneth J. Boote. Molecular Identification and Characterization of Heat-Stress-Responsive Microgametogenesis Genes in Tomato and Sorghum - A Feasibility Study. United States Department of Agriculture, ottobre 2007. http://dx.doi.org/10.32747/2007.7591741.bard.

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Exposure to higher than optimal temperatures - heat-stress (HS) - is becoming increasingly common to all crop plants worldwide. Heat stress coinciding with microgametogenesis, especially during the post-meiotic phase that is marked by starch biosynthesis, is often associated with starch-deficient pollen and male sterility and ultimately, greatly reduced crop yields. The molecular basis for the high sensitivity of developing pollen grains, on one hand, and factors involved in pollen heat-tolerance, on the other, is poorly understood. The long-term goal of this project is to provide a better understanding of the genes that control pollen quality under heat-stress conditions. The specific objectives of this project were: (1) Determination of the threshold heat stress temperature(s) that affects tomato and sorghum pollen quality whether: a) Chronic mild heat stress conditions (CMHS), or b) Acute heat stress (AHS). (2) Isolation of heat-responsive, microgametogenesis-specific sequences. During our one-year feasibility project, we have accomplished the proposed objectives as follows: Objectrive 1: We have determined the threshold HS conditions in tomato and sorghum. This was essential for achieving the 2nd objective, since our accumulated experience (both Israeli and US labs) indicate that when temperature is raised too high above "threshold HS levels" it may cause massive death of the developing pollen grains. Above-threshold conditions have additional major disadvantages including the "noise" caused by induced expression of genes involved in cell death and masking of the differences between heatsensitive and heat-tolerant pollen grains. Two different types of HS conditions were determined: a) Season-long CMHS conditions: 32/26°C day/night temperatures confirmed in tomato and 36/26°C day maximum/night minimum temperatures in sorghum. b) Short-term AHS: In tomato, 2 hour exposure to 42-45°C (at 7 to 3 days before anthesis) followed by transfer to 28/22±2oC day/night temperatures until flower opening and pollen maturation, caused 50% reduced germinating pollen in the heat-sensitive 3017 cv.. In sorghum, 36/26°C day/night temperatures 10 to 5 days prior to panicle emergence, occurring at 35 days after sowing (DAS) in cv. DeKalb28E, produced starch-deficient and sterile pollen. Objective 2: We have established protocols for the high throughput transcriptomic approach, cDNA-AFLP, for identifying and isolating genes exhibiting differential expression in developing microspores exposed to either ambient or HS conditions and created a databank of HS-responsivemicrogametogenesis-expressed genes. A subset of differentially displayed Transcript-Derived Fragments (TDFs) that were cloned and sequenced (35 & 23 TDFs in tomato and sorghum, respectively) show close sequence similarities with metabolic genes, genes involved in regulation of carbohydrate metabolism, genes implicated in thermotolerance (heat shock proteins), genes involved in long chain fatty acids elongation, genes involved in proteolysis, in oxidation-reduction, vesicle-mediated transport, cell division and transcription factors. T-DNA-tagged Arabidopsis mutants for part of these genes were obtained to be used for their functional analysis. These studies are planned for a continuation project. Following functional analyses of these genes under HS – a valuable resource of genes, engaged in the HS-response of developing pollen grains, that could be modulated for the improvement of pollen quality under HS in both dicots and monocots and/or used to look for natural variability of such genes for selecting heat-tolerant germplasm - is expected.

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Shoseyov, Oded, Steven A. Weinbaum, Raphael Goren e Abhaya M. Dandekar. Biological Thinning of Fruit Set by RNAase in Deciduous Fruit Trees. United States Department of Agriculture, agosto 1993. http://dx.doi.org/10.32747/1993.7568110.bard.

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Fruit thinning is a common and necessary practice for commercial fruit production in many deciduous tree fruit species. Fruit thinning in apple may be accomplished with a variety of chemical thinning agents, but the use of these chemicals is a subject of environmental concern. It has been shown recently that RNase enzyme, secreted from the stigma and the style, inhibits pollen germination and pollen tube elongation. In this study we have been able to show that Aspergillus niger B-1 RNase can effectively inhibit peach and apple pollen germination, and tube elongation in-vitro, as well as thin fruit in peach and apple, and reduce the number of seeds in citrus. The objectives of the research were to detrmine the conditions for effective thinning of (USA and Israel), develop fermentation process for cost effective production of RNase from A. niger. (Israel), and clone apple S-RNase cDNA (USA). All the objectives of the research were addressed. We have determined the optimal fermentation conditions for cost effective production of the A. niger at a 20,000 liters scale. TheA. niger B1 RNase was isolated to homogeneity and its kinetic and biochemical properties including its N-terminal sequence were fully characterized. The field test results both in Israel and California have shown variability in effectiveness and more work is needed to define the RNase concentration necessary to completely inhibit pollen development. Plant transformation vectors expressing anti-sense apple S-RNase genes were constructed (USA) with an attempt to produce self compatible transgenic apple trees. Bovine S-Protein cDNA was cloned and successfully expressed in E. coli (Israel). Plant transformation vector expressing the S-Protein gene was constructed (USA) with an attempt to produce transgenic plants expressing S-protein in the style. Exogenous application of S-peptide to these plants will result in active RNase and consequently prevention of fertilization.

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Veilleux, Richard, e David Levy. Potato Germplasm Development for Warm Climates. United States Department of Agriculture, ottobre 1992. http://dx.doi.org/10.32747/1992.7561057.bard.

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Complex potato hybrids derived from crosses between cv. Atlantic and 11 clones of three genomic compositions, all with an unadapted component from previously identified heat tolerant accessions, were evaluated in the field in Israel and Virginia and in controlled environments in Israel. Heat tolerance was exhibited in the field by the ability of many of these hybrids to tuberize under severe heat stress when cv. Atlantic did not tuberize at all. The complex hybrids also exhibited fewer internal defects (heat necrosis, hollow heart) than Atlantic. Studies to determine if heat stress applied during anther culture or to pollen samples prior to pollination could affect gametic selection towards more heat tolerant progenies were also undertaken. There was some evidence of greater heat tolerance (longer survival under heat stress) in the anther-derived population that had been regenerated under heat stress. The seedlings resulting from crosses with heat-treated pollen also exhibited greater haulm growth under heat stress compared with controls. However, the poor adaption of the germplasm prevented a firm conclusion about gametic selection. The introduction of exotic germplasm into cultivated potato has considerable potential to adapt potato to nontraditional growing seasons and climates. However, such hybrids will require continued selection and evaluation to retain the traits required for commercial production.

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Hodul, M., H. P. White e A. Knudby. A report on water quality monitoring in Quesnel Lake, British Columbia, subsequent to the Mount Polley tailings dam spill, using optical satellite imagery. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330556.

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In the early morning on the 4th of August 2014, a tailings dam near Quesnel, BC burst, spilling approximately 25 million m3 of runoff containing heavy metal elements into nearby Quesnel Lake (Byrne et al. 2018). The runoff slurry, which included lead, arsenic, selenium, and vanadium spilled through Hazeltine Creek, scouring its banks and picking up till and forest cover on the way, and ultimately ended up in Quesnel Lake, whose water level rose by 1.5 m as a result. While the introduction of heavy metals into Quesnel Lake was of environmental concern, the additional till and forest cover scoured from the banks of Hazeltine Creek added to the lake has also been of concern to salmon spawning grounds. Immediate repercussions of the spill involved the damage of sensitive environments along the banks and on the lake bed, the closing of the seasonal salmon fishery in the lake, and a change in the microbial composition of the lake bed (Hatam et al. 2019). In addition, there appears to be a seasonal resuspension of the tailings sediment due to thermal cycling of the water and surface winds (Hamilton et al. 2020). While the water quality of Quesnel Lake continues to be monitored for the tailings sediments, primarily by members at the Quesnel River Research Centre, the sample-and-test methods of water quality testing used, while highly accurate, are expensive to undertake, and not spatially exhaustive. The use of remote sensing techniques, though not as accurate as lab testing, allows for the relatively fast creation of expansive water quality maps using sensors mounted on boats, planes, and satellites (Ritchie et al. 2003). The most common method for the remote sensing of surface water quality is through the use of a physics-based semianalytical model which simulates light passing through a water column with a given set of Inherent Optical Properties (IOPs), developed by Lee et al. (1998) and commonly referred to as a Radiative Transfer Model (RTM). The RTM forward-models a wide range of water-leaving spectral signatures based on IOPs determined by a mix of water constituents, including natural materials and pollutants. Remote sensing imagery is then used to invert the model by finding the modelled water spectrum which most closely resembles that seen in the imagery (Brando et al 2009). This project set out to develop an RTM water quality model to monitor the water quality in Quesnel Lake, allowing for the entire surface of the lake to be mapped at once, in an effort to easily determine the timing and extent of resuspension events, as well as potentially investigate greening events reported by locals. The project intended to use a combination of multispectral imagery (Landsat-8 and Sentinel-2), as well as hyperspectral imagery (DESIS), combined with field calibration/validation of the resulting models. The project began in the Autumn before the COVID pandemic, with plans to undertake a comprehensive fieldwork campaign to gather model calibration data in the summer of 2020. Since a province-wide travel shutdown and social distancing procedures made it difficult to carry out water quality surveying in a small boat, an insufficient amount of fieldwork was conducted to suit the needs of the project. Thus, the project has been put on hold, and the primary researcher has moved to a different project. This document stands as a report on all of the work conducted up to April 2021, intended largely as an instructional document for researchers who may wish to continue the work once fieldwork may freely and safely resume. This research was undertaken at the University of Ottawa, with supporting funding provided by the Earth Observations for Cumulative Effects (EO4CE) Program Work Package 10b: Site Monitoring and Remediation, Canada Centre for Remote Sensing, through the Natural Resources Canada Research Affiliate Program (RAP).

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