Pollen Analysis Of Honey Research Articles

Bee–plant interactions identified by pollen analysis of honey from the stingless bee Tetragonisca fiebrigi (Schwarz, 1938) in southern Brazil

Pollen analysis of honey reveals information about bee–plant interactions and networks that, in some cases, are lost through mere observation of bees on flowers. This information on bee–plant interactions is valuable for the protection of bees and vegetal species and pollination of crop plants. To provide insights into bee–plant interactions, palynological evidence was developed from the collection of honey. The objective of this study is to determine the plants that the bees (Tetragonisca fiebrigi) visit for honey production in southern Brazil (Rio Grande do Sul). For this, 24 honey samples were collected from five regions of northeastern Rio Grande do Sul, southern Brazil. A total of 64 pollen types were found in the honey samples from T. fiebrigi in southern Brazil, mainly from trees. The most common pollen types in the samples were from Schinus terebinthifolia, Schizolobium parahyba, Handroanthus sp., Morus nigra, and Rosa cf. grandiflora. The pollen grains show a high diversity of plants, including those with important ecological functions.

Nectar sources of Asian honeybees (Apis cerana Fabricius) in West Bengal: determining by pollen analysis of honey and bee’s crop-nectar

: Understanding nectar sources is crucial for sustainable apiculture with Apis cerana, yet information on these sources remains limited. We conducted pollen analysis of honey and bees’ ingested nectar (mainly crop content) to determine the nectar sources of this honeybee species in West Bengal, India. Diverse pollen types were obtained from honey (33) and crop-nectar samples (47). A few pollen types came from non-nectariferous plants, and most came from actual nectariferous plants. Predominant pollen types in honey samples were Calendula officinalis, Eucalyptus tereticornis, and Peltophorum pterocarpum. The very frequent pollen types obtained from crop-nectar were Eucalyptus tereticornis, Peltophorum pterocarpum, and Tridax procumbens. In conclusion, versatile pollen types (that were obtained from honey and bee’s crop-nectar), indicating that the Asian honeybee (Apis cerana) is a generalist visitor, collect nectar from a large number of plant species. Our results also conclude that pollen analysis of bees’ crop-nectar can provide vital information about their nectar sources (excluding a few pollen types of non-nectariferous plants) in addition to the traditional honey analysis.

Honey pollen analysis in selected districts of North Wollo zone, Amhara region, Ethiopia

Melissopalynology plays a pivotal role in identifying and managing the geographical and botanical origins of honey. In this study, forty-five honey samples were collected from three potential districts in the North Wollo zone, Ethiopia. The pollen grains of these samples were analyzed using the procedures outlined by the International Commission for Bee Botany (ICBB) to determine the botanical sources of the honey. Among the samples, twenty-five were classified as monofloral, while the remaining twenty were identified as multifloral honey. Nineteen plant species from twelve different plant families were identified as the honey bee floras in the North Wollo zone. The dominant families, representing over 45% of the pollen grains in the samples, were Asteraceae (9 samples), Myrtaceae (5 samples), Papilionaceae (4 samples), Fabaceae (2 samples), Hypericaceae (2 samples), Acanthaceae (1 sample), Brassicaceae (1 sample), and Ericaceae (1 sample). Bidens spp., Trifolium rueppellianum, and Eucalyptus globulus emerged as the top three honey bee floras in terms of relative percentage and frequency. Furthermore, eleven samples exhibited a high diversity index range (H) of 1.56% in Lasta and 1.01% in the Meket districts, while the remaining thirty-four samples showed a lower diversity index ranging from 0.31 to 0.99. Our findings underscore the importance of conserving bee floras to enhance honey production and ensure sustainability in beekeeping practices in the North Wollo Zone.

Honeybee Floral Diversity of Gemachis Forest, West Hararghe Zone, Oromia Regional State, Ethiopia

The study was conducted in Gemachis forest from October 2019 to November 2020, which is an important area of biodiversity conservation, tourism attraction and carbon sequestration for modulating climate change. The forest is also very important for honey production and other non-timber forest products. The study was designed with the objective of assessing honey bee floral diversity of the forest. For the inventory of bee forages a transect line were made in three selected altitudinal strata. Honey samples also were obtained from the three agro ecologies of the forest: Arer (high altitude), Chafe kebene (medium altitude) and Sororo (low altitude). The pollen spectrum of the honey was analyzed to determine the botanical and geographical origin of the honey. According to inventory of the honeybee flora, forty-eight (48) bee plant species were identified; belonging to 33 families, of which <i>Fabaceae</i>, <i>Roseaceae</i> and <i>Verbenaceae </i>were the most frequent families in the study area. Among these bee forages 54.1% were shrub 16.6% were trees and 29.1% were herbs. From identified bee forages, <i>Solanium spp</i>, <i>Andropogon abyssinica</i>, <i>Guizotia spp</i> and <i>Hypoestes forskaolii</i> were the most abundant bee flora species in the study area. The pollen analysis of honey revealed that, two types of monofloral honey types were identified in the area which includes <i>Guizotia spp</i> and <i>Eucalyptus globulus</i> accounting for 74.9% and 54.9% pollen frequency respectively. Thus, beekeepers should conserve the forest for sustainable honey production since the forest is endowed with good honeybee plant diversity.

Melissopalynology in Brazilian seacoast mangrove areas, a mini review

Along the Brazilian coast, there are several types of mangroves with a variable predominance of trees of the genera Avicennia and Rizophora, as well as of the Laguncularia racemosa species. Mangrove beekeeping is a potential alternative source of income for many coastal communities in Brazil. Research activities on melissopalynology were initiated on Apis mellifera bees mainly by Barth and Luz in Rio de Janeiro, and with native bees by Kerr et al. in Maranhão States during the last century. Pollen analysis of honey, bee pollen and propolis were presented covering the Brazilian macroregions of the south, southeast, northeast and north. Bees showed preferential interest in Laguncularia racemosa in the southeast region. Studies with native bees are underway in an urban mangrove area of Rio de Janeiro. Laguncularia pollen occurred in reduced proportions in both honey and bee pollen. Avicennia predominated in the northeast region samples. Two samples of honey obtained from indigenous bees in the State of Espírito Santo, one sample from Maranhão and one sample of honey from Apis mellifera from Pernambuco, showed both Laguncularia and Avicennia pollen. All mangrove areas studied clearly showed the importance of Laguncularia racemosa. Studies of propolis highlighted the importance of vegetation along the inner edges of mangroves, such as Dalbergia ecastaphyllum, Schinus terebinthifolia and Symphonia globulifera.

Comparing the acetolysed and hydrated methods for the pollen analysis of honey

Melissopalynology is an integral part of honey analysis and indicates the honey's botanical and geographical origin. Two preparation methods for light microscopy are commonly and interchangeably used in laboratories: acetolysis and hydration of honey samples. In this study, an extended comparison of the two methods was performed. Eight honey samples from eight locations in central Europe were analysed according to both standard procedures. We identified the pollen grains with 1000× magnification to the lowest possible taxonomic rank and counted out the relative abundances of each pollen type in the sample. In addition, potential other biases that might affect the results were investigated by analysing one honey sample multiple times with each method, consecutively. Across all honey samples, more pollen types were identified with the hydrated method (136) compared to the acetolysed method (95). For the hydrated method, less washing steps were necessary and a higher amount of pollen grains remained. No taxa-specific loss could be observed, apart from Myosotis sp., which was present in significantly lesser amounts in acetolysed compared to hydrated samples. This study shows a detailed analysis of the advantages and disadvantages of the two methods, which are also highlighted in a side-by-side comparison box. Both methods are equally suitable to perform melissopalynological analysis of the most common pollen types and pollen type combinations in honey. However, to identify the largest variety of pollen types in honey samples, the hydrated method is more efficient.

Functional value of biologically active honey components

The article shows data on diastase activity and pollen analysis of honey from apiaries in the south of the Tyumen region. The research was conducted in the period 2017-2022. Honey maturation is a complex biochemical process in which biologically active substances, which include lysozyme and amylase, formed in the digestive glands of worker bees, play a significant role. They provide honey with high biological properties. Lysozyme is an antibacterial enzyme produced in the body of animals that prevents the penetration of microbes, viruses and fungi into honey. Amylase - breaks down the complex carbohydrates of nectar, converting them into glucose and fructose. These enzymes in bees are formed to a greater extent in the maxillary and pharyngeal glands. These are the high biological properties of honey. During the work on the pollen analysis of honey, it was revealed that the honey of apiaries in the south of the Tyumen region is polyphlorous, since pollen grains of various honey plants were identified in the studied honey samples, which included linden, sweet clover, rapeseed, esparcet, winter cress, dandelion, clover, sow thistle. The results of diastase activity determination showed that in experimental honey samples the diastase number was in the range from 8.0 to 23.8%, high diastase activity characterizes the quality of honey, since it, undergoing prolonged biochemical treatment, is more saturated with enzymes and biologically active substances. According to the research results, honey with high diastase activity includes samples from apiaries of Yalutorovsky and Isetsky districts.

Pollen analysis of honey and pollen stored by Melipona (Melikerria) fasciculata Smith, 1854 (Apidae Meliponini), in an Amazon and Cerrado transition area, Maranhão, Brazil.

The identification of meliponicultural flora is fundamental for the preservation of bees, as well as enabling the development of pollinator management and reforestation programs. In this context, this study aimed to investigate the types of pollen found in the honey and pollen pots of the Melipona fasciculata bee in Arari, State of Maranhão, between August 2022 and July 2023. 40 types of pollen were identified, distributed among 18 botanical families, with Fabaceae standing out (46.15% in pollen pots and 37.86% in honey pots), Myrtaceae (11.53% in pollen and 13.51% in honey) and Rubiaceae (7.69% in pollen and 5.40% in honey). Sapindaceae, in the honey pots, accounted for 5.40%. The other families showed lower percentages, 3.84% in the pollen pots and 2.70% in the honey pots. In terms of similarity, two distinct groups were observed in both the pollen and honey pots. In the pollen pots, group A (May-June ~ 97%) and group B (Feb-Mar ~ 99%) stood out, while in the honey pots, group A (Mar-Apr ~ 98%) and group B (Jun-Jul-Sept ~ 98%) showed the highest percentages. These findings highlight the wide range of resources used by the M. fasciculata species, as well asits preference for Fabaceae and Myrtaceae, due to the diversity and availability of trophic resources. An understanding of the meliponicultural flora is essential to support effective conservation strategies, which aim not only to guarantee the survival of the bees, but also to ensure the continued production of honey, a resource of great importance to local communities.

Diversity of Bee Floral Resources and Honey Production Calendar in Ethiopia’s Southwest Shoa Zone

Bee flora resources are essential for the development of beekeeping. This study aimed to identify the diversity of key bee forage plants, establish honey harvesting calendars, and assess different types of monofloral honey in the area. Data collection methods included a bee plant inventory, pollen collection, and honey pollen analysis. A total of 122 plant species were identified as bee plants, with 44.26% being shrubs and 27.87% being trees. These bee plants were distributed across three districts, accounting for 37.40% of the plant species, indicating a broader ecological distribution than local species. Wonchi district exhibited the highest diversity of bee plants (H′ = 4.7), followed by Waliso (H′ = 4.55). Three honey harvesting periods were identified: November, January, and June. Additionally, three distinct types of monofloral honey were produced: Erica arborea honey in January, Eucalyptus camaldulensis honey in June, and Guizotia scabra honey in November. A shortage of bee forages was noted in February, March, July, and August across all districts. The southwest Shoa zone (comprising Wonchi, Waliso, and Amaya districts) shows potential for sustainable and commercial beekeeping based on the available bee flora resources. To ensure sustainability, it is crucial to maintain the existing bee flora and increase the propagation of multipurpose plant species. Additionally, on‐farm demonstrations highlighting the importance of floral and honey calendars for effective colony management are recommended.

Identification and Establishing Floral Calendar in Jimma Zone of Oromia Ethiopia

Bee flora resources are crucial for the development of beekeeping. The study aimed to find and construct a flowering calendar for bee plants in order to produce many batches of honey. Data were collected through bee plant inventory, pollen collection and honey pollen analysis. Based on bee plant inventories, pollen load collection, and honey pollen analysis, 103 plant species were identified as nectar and pollen sources for honeybees. Ageratum conizoides, Guizotia scabra, Cordia africana, Datura arborea, Plantago lanceolata, Rumex nervosus, and Justicia schimperiana were the most common honey-producing plants in the area. The fresh weight of pollen gathered at various months of the year revealed that a substantial amount of pollen was collected in September, October, and November, but the incoming pollen weight decreased in March and July. The area's peak honey flow period began in November and lasted until early December or late February. The modest honey flow also occurred in May and June. Pollen examination of honey samples indicated three monofloral honey types: Guizotia spp., Vernonia, and Croton monofloral honey types, with pollen frequencies ranging between 45% and 100%. The study indicated that the floral calendar of bee forages is completely reliant on the seasonal availability of food sources, and beekeepers should be aware of how to manage honeybee colonies in accordance with the flowering calendar in their area in order to enhance the frequency of honey production.

Pollen Analysis of Honeys in Arıt Region (Bartin)

Bu çalışmada Bartın’a yaklaşık 32 km uzaklıkta olan Arıt ilçesine bağlı köy ve mahallelerinden 2008 ve 2009 yıllarında toplam 13 bal örneği toplanmış ve bu örneklerde polen analizi yapılmıştır. Yapılan bal analizlerinde dominant, sekonder, minor ve eser miktarda polenler saptanmıştır. Bal örneklerinde gözlenen polenler 31 familyaya ait olup bu polenlerin 17’si cins ve 20’si tür düzeyinde teşhis edilmiştir. Bal örneklerinde dominant oranda bulunan polenler Castanea sativa ve İlex colchica, sekonder oranda bulunan polenler ise Castanea sativa, Ligustrum vulgare, Pyrus sp., Prunus sp. ve Apiaceae taksonlarına aittir. Bal örneklerinin hepsinde Castanea sativa polenleri gözlenmiştir. Görüldüğü gibi arılar her ne kadar çeşitli bitki türlerinden nektar toplasalar da bazı bitki türlerinden daha çok yararlanmakta ve bunlar yörenin önemli nektarlı bitkilerini oluşturmaktadır. Bu bitkilerden alınan polenler dominant polenleri oluşturarak balın kalitesini etkilediği gibi sekonder hatta minör durumdaki polenlerde ait olduğu bitkiye bağlı olarak balın kalitesi üzerine etkili olabilmektedir.

КАЧЕСТВЕННАЯ ОЦЕНКА МЁДА ПАСЕК ТЮМЕНСКОЙ ОБЛАСТИ

The article presents data on diastase activity and pollen analysis of honey from apiaries in the south of the Tyumen region. The research was conducted in the period 2017–2022. Honey maturation is a complex biochemical process in which biologically active substances, which include lysozyme and amylase, formed in the digestive glands of worker bees, play a significant role. Lysozyme provides bactericidal properties of honey, amylase – breaks down complex carbohydrates to their monomers. When conducting a pollen analysis of honey, it was revealed that the honey of apiaries in the south of the Tyumen region is polyfloric, since pollen grains of various honey plants were identified in the honey samples studied, which included linden, sweet clover, rapeseed, esparcet, surepka, dandelion, clover, osot. The results of the determination of diastase activity showed that in the experimental samples of honey, the diastase number was in the redistribution from 13,9 to 20,4 units, high diastase activity characterizes the quality of honey, because after undergoing a long-term biochemical treatment, it is more saturated with enzymes and biologically active substances. According to the research results, honey with high diastase activity includes samples from apiaries of Yalutorovsky and Isetsky districts.

Pollen analysis of honey from Laghouat region (Algeria)

A microscopic analysis of 41 samples of honey obtained from several locations in the Laghouat region revealed the presence of 98 pollen types belonging to 48 families. Asteraceae, Fabaceae and Nitrariaceae were present in all the samples. Brassicaceae, Rhamnaceae and Apiaceae were identified in more than 80% of the samples. The families with highest diversity of pollen types were Fabaceae and Asteraceae with 13 and 11 types, respectively, Apiaceae and Boraginaceae with five types each. Twenty-seven honey samples (65.85%) were found to be monofloral and the remaining 14 polyfloral. The pollen types from Ziziphus lotus, Peganum harmala, Echium sp., Tamarix sp., Lotus, Eucalyptus sp., Eruca vesicaria and Thapsia garganica appeared as the predominant pollen. Eighteen pollen types were classified as very frequent, present in more than 50% of the samples. The number of pollen types identified per sample ranged between 14 and 40 (mean of 24.41). For the quantitative analysis, the pollen content of the studied honey samples ranged from medium (class II, 48.78% of the samples) to high (class III, 53.65% of the samples), where the pollen density ranged from 26 607 to 660 992 in 10 g of honey, with an average of 160 880 grains per 10 g.

Methods Employed in the Determining Nectar and Pollen Sources for Bees: A Review of the Global Scenario

Abstract Flowering plants and pollinators are in a mutualistic association, where pollinators collect floral resources and plants receive pollination services. Bees and other pollinators are declining in many parts of the world, and their loss affects the functional composition of fauna, flora, and habitats. Different strategies are being deployed to improve pollinator services, including the management of bees. Sustainable management of a bee species strongly depends on floral resource availability. Therefore, beekeepers need to have adequate knowledge about the surrounding vegetation (especially nectar and pollen sources for the bee species). Diverse methodologies are used around the world to determine floral resources for bees. Field surveys and pollen analysis of honey, corbicular/scopal pollen loads, residual pollens in brood cells, forager’s body surface pollen content, and internal organs (gut, intestine, crop, etc.) were used by the researchers. For pollen identification, most researchers carried out microscopy-based methods. However, pollen DNA-based methods were also used by researchers in recent years. Regarding the morphology-based identification, most researchers processed pollen samples according to Erdtman’s acetolysis method to increase the visibility of diagnostic characteristics of the pollen grains. The method specified by the International Commission for Bee Botany was used to conduct qualitative and quantitative pollen analysis on honey samples. For quantitative pollen load analysis, researchers used numerous techniques that may have been the most effective. Our discussion about the different techniques utilized to determine floral resources of a bee species will be helpful for researchers in selecting a suitable protocol and may assist in developing superior methodologies.

Honeybee Colony Management Practices and Identification of Honeybee Floras in Eastern Amhara, Ethiopia

The art and science of managing and breeding honeybee colonies in the artificial hive for the sake of the economy are known as beekeeping or apiculture. It contributes to the increment of food and cash crop products through pollination services and protects and stabilizes fragile environments. The sector depends on floras to survive and produce honeybee products. Those plants were categorized as either nectar or pollen or both depending on their content. Assess the honeybee colony management practice and identification of honeybee flora intended to document the indigenous knowledge for the establishment of the best management decisions. Therefore, this study aimed to assess the honeybee colony management practices and identify the honeybee floras in eastern Amhara, Ethiopia. This study was conducted in the selected district of eastern Amhara based on the relative suitability and potential for beekeeping. A questionary survey was conducted for 122 beekeepers. Additionally, key informant interviews and honey pollen analysis were performed to support the questionary survey. The result of this study showed the beekeeper farmers had trouble with seasonal feed shortages for their honeybee colonies besides absconding and swarming were also prominent in the area. Furthermore, this study revealed that about 104 bee flora species were identified, which include shrubs, trees, herbs, and crops with the major proportion of shrubs. Most honeybee floras were perennial plants. Additionally, the seasonal bee forage fluctuation could be categorized into dearth, moderate, and honey flow season. The dearth period occurred from January-March and July-August. The moderate period was from April-June, and the honey flow period was from September-November. Therefore, seasonal management of the colonies should be adjusted with the dearth periods. Further study must be done about the frequency and density of the honeybee plants.

Physicochemical and antioxidant properties of Coffea arabica honey from Western Oromia, Ethiopia

Coffea arabica is one of the most widely consumed and marketed commodities in the world. The study was designed to characterize C.arabica honey for botanical composition, physicochemical parameters, and antioxidant properties of honey. Twelve honey samples of C. arabica honey were collected during the flowering period of coffee flowers from the Zander hive. The physicochemical properties of honey and the Botanical origin of honey were determined based on Harmonized methods of the International Honey Commission. The antioxidant power of the coffee monofloral honey samples was determined by dissolving 1.5 gm of honey with 25 ml distilled water and mixing it with 25ml methanol and placed at 25◦C for sixty minutes of maceration using a temperature shaker. The pollen count percentage from honey indicated that all honey samples collected from Gera, Gomma, Yayu, and Manna districts were identified as coffee monofloral honey representing 84%, 93%, 75%, and 73 % of pollen count respectively. The mean moisture, ash, HMF, EC, FA, pH, fructose, glucose and sucrose content of Coffea arabica honey were 22.48%, 0.21%, 11.88, 0.49 mS/cm, 13.44 meq/Kg, 3.32, 32.77%, 32.9%, and 3.57% respectively. The total phenol and flavonoid content range from 42.1-82.1 and 21.7-59.7 mg/100 g of GAE/g respectively while the radical scavenging activity ranges from 60.2- 66.3%. The pollen analysis of honey from the area is coffee monofloral honey since its pollen count exceeds more than 45% and the honey quality also meets the Ethiopian and International standards. The antioxidant power of Coffee honey has a considerable amount of polyphenolics which have relevant antiradical activity.

Pollen analysis of honeys from Yığılca region (Düzce), Turkey

The aim of this study is to determine the plant species preferred by Apis mellifera L., which is a valuable genotype in terms of vitality and high honey production. For this purpose, seven honey samples from Yığılca region in Düzce (Turkey) were examined for pollen analysis. As a result of the pollen analysis on these samples, it was determined that Yığılca local honeybee use pollen grains of 43 different taxa from 26 families. Six samples of honey were unifloral (> 45% pollen of one taxon in sample) with four being unifloral for Rhododendron ponticum and two for Castanea sativa. One sample of honey was classified as multifloral with the percentages of secondary and rare pollen groups. The honeys had contained 14 to 30 different types of pollen. The average number of pollen types per honey was 21. The dominant groups of pollen grains were determined as Rhododendron ponticum in 4 samples and Castanea sativa in 2 samples. Secondary pollen components were from 3 taxa: Fagus orientalis, Rhododendron ponticum and Quercus sp. Four pollen types occurred as ‘minor’ types and pollen grains of 37 taxa were in rare quantities. Asteraceae, Fabaceae, Fagaceae, Lamiaceae and Rosaceae were the most represented families in honey samples.

Determination of Nectar Resources through Body Surface Pollen Analysis: A Study with the Stingless Bee Tetragonula iridipennis Smith (Apidae: Meliponini) in West Bengal, India

Knowledge about floral resources is essential for bee management and conservation. Pollen analysis of honey is the most traditional method for determining the nectar resources of a bee species. However, the collection of honey samples is difficult in cavity-nesting natural stingless bee colonies. Furthermore, it is detrimental to the wild bee’s colony and may threaten their survivability. We analyzed adhered body surface pollen of incoming nectar foragers (which were smeared incidentally during nectar foraging) as an alternative method to determine nectariferous flora of Tetragonula iridipennis in West Bengal, India. By this method, we have identified 75 pollen types. The number of obtained pollen types was lower in the human-altered habitats of Midnapore city (44 pollen types) than the semi-natural habitats of Garhbeta (71 pollen types). Excluding a few pollen types of non-nectariferous plants, most of the pollen types came from nectariferous plants of both crop and non-crop species. Non-crop flowering plants (viz. Ailanthus excelsa, Borassus flabellifer, Eucalyptus tereticornis, Lannea coromandelica, Peltophorum pterocarpum, and Tectona grandis) provided a significant amount of nectar to the bee species and, therefore, play an important role in the conservation of the bee species.

Botanical origin and characterization of monofloral honeys in Southwestern forest of Ethiopia.

The study was conducted to identify and characterize the monofloral honey types found in the Gesha‐Sayilem forest. A total of 15 honey samples were collected during the honey flow seasons. For honey pollen analysis, the method recommended by the International Commission for Bee Botany and harmonized methods of the International Honey commission were used. Data were analyzed using one‐way ANOVA, PCA, and Pearson correlation coefficients. Three monofloral honey types were identified, such as Schefflera abyssinica honey, Croton macrostachyus honey, and Vernonia amygdalina honey types. The mean moisture content of the honey samples of Vernonia amygdalina honey was 18.3 ± 1.02%, that for Schefflera abyssinica honey 18.1 ± 1%, and 21.2 ± 1.05% for Croton macrostachyus honey. The HMF value of the Vernonia honey ranged from 1.1 to 1.3 mg/kg, with a mean value of 1.2 ± 0.1 mg/kg; that of Schefflera abyssinica honey ranged from 2.2 to 2.5, with a mean value of HMF 2.3 ± 0.15; and that of Croton honey ranged from 2.4 to 2.6 mg/kg, mean value of 2.56 ± 0.15 mg/kg. There was a significant difference in the free acid content of honey samples due to the botanical origin of honey and sampling locations (p < .05). The electrical conductivity of honey samples in the Gesha‐Sayilem forest was found within an international range, with a maximum limit of 0.8 mS/cm for most nectar honey. There was a significant strong correlation between proline, free acid, and sucrose. Moisture content was positively correlated with electric conductivity, due to the dependable nature of electrical conductivity on honey moisture. The study area honey meets the basic honey quality standards both of the national and international honey quality specifications, except that the moisture content of croton honey which was some what out of the accepted range.

Assessment of pollen and honey diet of Tetragonisca angustula fiebrigi Schwarz in the Chaco dry forest by using pollen analysis

Pollen and honey resources composing the diet of Tetragonisca angustula fiebrigi Schwarz were assessed using pollen analysis of wild colonies sampled in two kinds of native dry forests of the Chaco region. Different measurements: direct pollen count, relative volume, diversity and evenness indices, value of importance of species (SI), and index of relative importance (IRI) were compared. The IRI identified the most important pollen resources as Prosopis (IRI = 1619), Schinopsis type (IRI = 1578), Trithrinax schizophylla (IRI = 972) and Capparicordis/Sarcotoxicum (IRI = 587), and according to SI the honey resources were Schinopsis type (SI = 117.41), Maytenus type (SI = 101.89), Prosopis (SI = 86.47) and Ziziphus mistol (SI = 50.93). The absolute pollen analysis of honey revealed that all samples were rich in pollen grains. Floral resources were most homogeneously foraged during spring and summer when a high number of flowerings were available and the highest temperatures were recorded. These optimal conditions for bee foraging activity also allowed for the highest diversity indices in these seasons. However, heterogeneous foraging and low diversity were detected during winter and autumn. Most pollen and honey resources belonged to generalised small flowers of diverse plant lineages. The IRI was more comprehensive to identify the most important pollen resources than the commonly used direct pollen count, as it also includes relative volume and frequency of occurrence, and SI was the most thorough for studying the honey resources. This study provides helpful information for sustainable meliponiculture and forest conservation.