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Properties and composition of honey are essential in providing information regarding their quality as well as in their differentiation based on production region characteristics, e.g., floral sources. This paper presents physicochemical properties and floral sources (botanical origin) of 21 honey samples obtained from arid and semiarid areas of Kenya, specifically, West Pokot, Baringo, and Kitui Counties. Physicochemical parameters which were analyzed to determine honey quality included moisture content, hydroxymethylfurfural (HMF), diastase activity, free acidity, and electrical conductivity. Values of these parameters were compared with those of the existing local, regional, and international standards for honey. Melissopalynological analysis (pollen analysis) was also carried out to provide information on botanical origin of the honeys. Results showed mean parameter values of moisture, 16.34%; HMF, 23.28 mg/kg; diastase activity, 10.67 Schade units; free acidity, 22.95 meq/kg; and electrical conductivity, 0.40 mS/cm. Free acidity and electrical conductivity values of honey samples obtained from West Pokot were significantly lower than the values of honeys from Baringo and Kitui. Eighteen (18) honey samples had all parameter values within the limits set in the East African, Codex Alimentarius, and the European Union directive standards for honey. Results also showed a total of 29 pollen types in the honey samples analyzed, and Acacia spp. was the predominant pollen type in 4 of the 21 honey samples. Findings of this study showed that Kenyan origin honeys can tap into the existing regional and international markets based on their quality which can be attributed to their botanical origin. Results of this study also suggested that honey producers have undertaken appropriate measures in honey harvesting, processing, handling, and storage. However, there is a need to build capacity of producers whose honey were of unacceptable quality. This would involve training on proper honey production, processing, and handling practices as well establishment of honey collection and processing centres at the local level in order to improve honey quality. This will enhance access to existing honey markets. Conservation of bee floral sources would also be needed to maintain honey quality.

The floral volatiles of blackcurrant (Ribes nigrum) were collected in situ using the headspace technique. Eleven compounds were identified, including monoterpenes hydrocarbons and monoterpene ethers. The fragrance was emitted in a rhythmic manner, the maximum being in the middle of the photoperiod. Emission at 20° C vi'as significantly higher than at 10°C. The rhythmic nature of emission seemed to cease under conditions of constant light. However, a slight rise in emission during the second period in continuous light may indicate a eircadian control of emission. The signiflcance of flower volatiles in relation to pollination is discussed.

Nectar is a vital source of energy for bees and other pollinators and pollen represents the only source of protein in the diet of bees. Nectar and pollen quality and quantity can therefore affect foraging choices. Strawberry, Fragaria × ananassa (Rosaceae), is a flowering crop that requires insect pollination for the berries to develop optimally. The solitary red mason bee, Osmia bicornis L. (Hymenoptera: Megachilidae), occurs naturally but like the eusocial western honeybee, Apis mellifera mellifera L. (Hymenoptera: Apidae), it is also a commercially reared pollinator used in strawberry production. We hypothesized that strawberry nectar and pollen quality would affect the foraging choice of these two types of bees. In this study nectar and pollen quality is represented by various levels of sugar and protein content, respectively, as well as the number of open strawberry flowers in the experimental field, would affect the foraging choice of these two types of bees. Consistent with previous studies, we found significant and major differences between strawberry varieties in proportions of sucrose in the nectar sugar and in pollen viability – a proxy for pollen protein content. All measured parameters had a significant effect on red mason bee visitation frequency. Contrary to expectations, honeybee foraging behavior was only affected by the number of open flowers and not by any of the quality parameters measured. Our findings indicate that red mason bees were capable of assessing nectar and pollen quality and prioritize accordingly. The pattern observed indicates that individual red mason bees changed foraging focus between strawberry varieties depending on whether nectar or pollen was collected. Our results suggest that targeted breeding of varieties toward high levels of nectar sugar and sucrose concentrations and high pollen protein content may increase pollination success from red mason bees and possibly other solitary bees.

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