RT - Journal Article T1 - Investigating Pollination of Astragalus spp. Species in Karsanak rangelands, Chaharmahal and Bakhtiari Province JF - rangelandj YR - 2022 JO - rangelandj VO - 16 IS - 2 UR - http://rangelandsrm.ir/article-1-1120-en.html SP - 396 EP - 412 K1 - Pollinoters bees K1 - Visitor insects K1 - Population size K1 - Reproduction K1 - Species extinction AB - Background and objectives: It is an interactive pollination with a long evolutionary history that plays an important role in the success of plant fertility. Without pollinators, many plants cannot reproduce. Astragalus species are the largest genus of flowering plants in the world and comprise 18% of the total flora of the country. Little is known about the reproductive biology of these species, although many genera of these species are rare in different geographical areas and have their own pollinators. The purpose of this study was to investigate the pollination of some rare and common species of astragalus in order to evaluate the factors affecting the rarity of the species. Methodology: In this study, pollination of 6 herbaceous astragalus species including three rare herbaceous species (As. Caraganae, As. Heterophyllus and As. Holopsilus) and three common herbaceous species (As. Angustiflorus, As. Curvirostris and As. Effusus) and 6 shrub astragalus species includes three rare shrub species (As. Cephalanthus, As. Camphylanthus and As. Cemerinus) and three common shrub species (As. Verus, As. Susianus and As. Rhodosemius) based on comparison of phenological characteristics of the plant including maximum plant height, flowering time, total number of flowers produced, flower longevity and seed set produced between rare and common astragalus species were studied. For each plant studied, twenty stands were selected for sampling and the number of pollinating insect visits was recorded for 15 minutes for each. To determine the relationship between pollinator action and the rarity and common of astragalus species, the seed sets produced by the species were compared. Finally, the mean of all data was tested by one-way analysis of variance in a completely randomized design. Results: Sampling of rare and common astragalus species led to the identification of a total of 9 species of pollinating bees (Apis melifera, Megachili sp, Osmia sp, Eucera sp, Andrena sp, Anthophora sp, Xylocopa sp, Bombus zonatus and Bombus armeniacus) belonging to three family (Apidae, Megachilidae and Andrenidae). The results of herbaceous astragalus species showed the highest number of flowers and the highest number of pollinators (As. Effusus species), maximum plant height (As. Angustiflorus species), the highest seed mass (As. Angustiflorus and As. Effusus species) and the lowest plant height and the lowest number of flowers (As. Curvirostris) belonged to common astragalus species. Herbaceous astragalus species (rare and common) were not different in terms of flowering season, but flower longevity was longer in rare astragalus species (As. Heterophyllus). The results of shrub astragalus species showed that the highest number of flowers and the highest number of pollinators (As. Rhodosemius species), the maximum plant height (As. Susianus species) and the highest seed mass (As. Verus species) belonged to the common astragalus species. The lowest number of flowers, pollinators and plant height (As. Cemerinus) belonged to rare astragalus species. In terms of flowering season, rare (spring) and common (summer) species were different and flower life was longer in rare species (As. Camphylanthus and As. Cephalanthus). Conclusion: The results showed that in homogenous species with similar vegetative form, the larger the number of flowers and the higher the height of these species, the more pollinators are attracted, which ultimately leads to more seed mass production in the species. In addition, it is possible that homosexual species have changed their flowering time to reduce competition in attracting pollinating species, and the greater the distance between this time difference compared to the flowering time of most species, the greater the success of the species. LA eng UL http://rangelandsrm.ir/article-1-1120-en.html M3 ER -