Every pollen grain tells a story: A palynological analysis of selected melliferous plant species native to the Sahara Desert with implications for honey origin determination

Abstract

Pollen analysis is essential for discerning the botanical and geographical origins of honey, ensuring authenticity, quality, and commercial value. The Sahara Desert in Algeria boasts unique floral diversity, with its melliferous plant species contributing to regional honey production. Nevertheless, a lack of comprehensive information on the pollen characteristics of these plants impedes precise identification of the geographical and botanical origins of Saharan honeys. Given the importance of understanding honey origin for quality assurance, this study addresses the challenge posed by the scarcity of melissopalynological data in the Sahara Desert. By offering a detailed characterization of Sahara Desert melliferous plant pollen, the research contributes valuable insights to the broader field of honey authentication and underscores its significance in the industry. Therefore, this study was conducted to characterize the pollen of melliferous plants in the Sahara Desert, which is essential for establishing a database that can aid in the determination of honey origins, protect against fraudulent activities, and support conservation efforts. This study aimed at the characterization of pollen of spontaneous melliferous plants from the Sahara Desert of Algeria to facilitate the determination of the geographical and botanical origin of honeys produced in this region. In three regions (Ghardaïa, Touggourt and Ouargla), pollen morphological features namely: polar length (PL) and equatorial diameter (ED), size, shape, apertures and exine ornamentations of 19 native plant species were studied through the sampling of ten flowers per plant and ten pollen grains per flower for each species (n = 3800 measurements). The surveyed plant species showed that medium-sized pollens (25–50 µm) were the most dominant (73.34 %), followed by slam-sized pollens (21.18 %), with the smallest size observed in Tetraena alba (PL = 18.98 ± 4.82 μm, ED = 18.95 ± 5.06 μm) and the largest size measured in Faidherbia albida (PL = 58.03 ± 4.65 µm, ED = 57.46 ± 4.70 μm). The most frequent forms of pollen in different species were prolate-spheroidal (32.68 %) and oblate-spheroidal (26.53 %). Diverse types of exine ornamentations and were detected at the pollen unit level with a dominance of reticulate (57.89 %). Tricolporate (42.11 %) and tricolpate (31.58 %) were the dominate pollen apertures. This study characterized pollen from Sahara Desert melliferous plants, which can aid honey origin determination, ensuring quality and supporting conservation, with implications in authentication, protection, and preservation of floral resources for sustained honey production.