The attractiveness of flowering herbaceous plants to bees (Hymenoptera: Apoidea) and hoverflies (Diptera: Syrphidae) in agro‐ecosystems of Central Spain

Abstract

1 Habitat management, with the aim of conserving pollinators in agro-ecosystems, requires the selection of the most suitable floral species in terms of their attractiveness to pollinators and a simplicity of agronomic management. 2 A randomized block design including 12 herbaceous plants was used to study their attractiveness to pollinators (insect visitation), their attractiveness efficiency (a combination of duration of flowering and insect visitation), their response to two different agronomic management practices (growing in mixed versus mono-specific stands; tillage versus no-tillage) and their potential weediness. 3 The flowers of Borago officinalis, Echium plantagineum, Phacelia tanacetifolia and Diplotaxis tenuifolia were attractive to bees, whereas Calendula arvensis, Coriandrum sativum, D. tenuifolia and Lobularia maritima were attractive to hoverflies. 4 A floral mixture resulted in a lower attractiveness efficiency to pollinators than D.tenuifolia, but higher than when compared with most of the mono-specific stands. On the other hand, although some of the most attractive plant species (P. tanacetifolia and C. arvensis) showed potential weediness, their self-seeding was reduced by tillage treatment. 5 Diplotaxis tenuifolia was the only plant with a high attractiveness efficiency to pollinators and efficient self-reproduction. Therefore, D. tenuifolia is highly recommended species for attracting bees and hoverflies in agro-ecosystems of Central Spain.

Can floral field margins improve pollination and seed production in corianderCoriandrum sativumL. (Apiaceae)?

“…In general, foraging of pollinators in different crop flowers is limited as a result of their short blooming period. In coriander, the blooming period varies from one region to another and, depending on the field conditions of the specific region, it can last for 20–40 days (Bendifallah et al ., ; Barbir et al ., ). Therefore, to maintain pollinators within the agricultural landscapes, it is necessary to complement them with additional floral sources where pollinators can forage before and after crop blooming.…”

“…is equally attractive for two groups of the most abundant pollinators in Mediterranean region (i.e. bees and hoverflies) (Barbir et al ., ). Accordingly, it has been hypothesized that a margin with this floral species can improve seed production in coriander and can attract as many pollinators as a mixed margin with various plant species.…”

“…Because flowers of coriander are characterized for their exposed nectaries, abundant pollen production and zygomorphic flowers (Koul et al ., ; Sinacori et al ., ), they are attractive to flies (mainly hoverflies), bees and beetles (Colley & Luna, ; Bendifallah et al ., ; Barbir et al ., ), which are the main pollinators of this crop. In general, foraging of pollinators in different crop flowers is limited as a result of their short blooming period.…”

Utilisation of plant functional diversity in wildflower strips for the delivery of multiple agroecosystem services

“…In a study investigating the plant characteristics associated with increased natural enemy abundance, the combined effect of maximum flower height, decreasing corolla width, floral area, and period of peak bloom was significantly associated with the increased abundance of natural enemies (Fiedler & Landis, ). In another study, the perennial wall‐rocket, Diplotaxis tenuifolia (L.) DC, was attractive to both bees and hoverflies and performed better than wildflower mixtures of which species were previously shown to attract either of the two arthropod groups (Barbir et al., ). Wild bees in agricultural landscapes have been shown to have a wide trophic niche and can access different flower functional groups.…”

Genome‐skimming provides accurate quantification for pollen mixtures

“…Direct observation of flower visits has been used in estimating bees' pollen resources, food range and niche overlap (Camillo & Garofalo, 1989;Connop, Hill, Steer, & Shaw, 2010). This approach is time-consuming (Ranta & Lundberg, 1981), and the results can be coarse in resolution because it does not differentiate variations in pollen collection efficiencies among and within pollinator species (Barbir, Badenes-Pérez, Fernández-Quintanilla, & Dorado, 2015;Bosch, 1992;Woodcock et al, 2013). Alternatively, analysis of pollen loads from pollinators is more straightforward and may provide more accurate evaluation on pollen compositions (Connop et al, 2010).…”