The effect of pollen source on seed traits and dispersability in the heterocarpic annual Crepis sancta

Aims The evolution and expression of dispersal-related traits are intertwined with those of other life-history functions and are manifested within various physiological constraints. Such a relationship is predicted between inbreeding levels and dispersability, which may be anatomically and ontogenetically linked so that the selection pressures on one may affect the other. While both the effect of inbreeding on reproductive success and on dispersal strategies received much attention, only a few studies considered both simultaneously. Furthermore, such studies often rely on two dichotomic representations of breeding and dispersal: using selfing vs. outcrossing as a representation of breeding level, and dispersal ratio as the sole representation of dispersal strategy. Methods Here we used pollination experiments in the heterocarpic Crepis sancta (Asteraceae) to expand in two different manners on the common practice of using dichotomic representations of breeding and dispersal. First, we used pollination treatments that represent a continuum from selfing through pollination by kin to pollination by a distant neighbor. Second, we measured a whole set of continuous morphological and dispersal-related traits, in addition to measurements of reproductive success and dispersal ratio. Important findings The proportion of developed capitula and the number of both dispersed and non-dispersed achenes were significantly lower in the self-pollination treatment in comparison to the out-crossed treatments. The effect of pollen sources on dispersal ratio was not statistically significant, though self-pollinated plants rarely produced non-dispersing seeds. Achene’s biomass increased with distance between parent plants, but pappus width did not, leading to a nonsignificant effect of pollination on falling velocity. Overall, pollen source affected mainly traits that were associated with reproductive output, but it had no clear effect on predominately dispersal-related traits. Such differences in the response of reproduction and dispersal traits to variation in pollen source suggest that dispersal-related selection is probably weak and/or masked by other forces.

The Antibacterial Activities of Lavandula stoechas and Crepis sancta Leaf and Flower Against Mastitis Pathogens and Enzymatic and Non-Enzymatic Antioxidant Activities of The Extracts

The antibacterial and antioxidant activities of Lavandula stoechas and Crepis sancta extracts on subclinical mastitis bacteria in cows have not been reported to the present day. The aim of this work was to investigate of the antibacterial and antioxidant potential of methanol extract from L. stoechas and C. sancta. Methanol extracts were screened for antibacterial activity against mastitis pathogens. The antibacterial activity was tested using disc diffusion and broth dilution method. In addition, the plant extracts were tested against the stable DPPH (1,1-Diphenyl-2-picrylhydrazyl) free-radical. Additionally methanol extracts were screened for enzymatic antioxidant activity. The methanol extract of C. sancta showed maximum inhibition zone against S. aureus-18 (16 mm). MIC (minimum inhibition concentration) value was determined as 3250 µg/mL for test bacteria. The highest radical scavenging capacity (62 %) was obtained from the flower extracts of L. stoechas and the leaf extracts of C. sancta. The methanol extract of C. sancta displayed a strong antioxidant activity (trolox equivalent = 1.6 mM/g). It was determined that the activities of catalase (CAT) and ascorbate peroxidase (AP) enzymes were higher at the flowers of L. stoechas compared to the leaves. The extracts of L. stoechas and C. sancta leaf and flower have antibacterial and antioxidant potential against subclinic mastitis causative agent Staphylococci species.

Tipificación de Crepis sancta (L.) Babc. (Compositae, Cichorieae)

Se discute la tipificación del nombre Crepis sancta (L.) Babc. in Unif. Calif. Public. Bot. 19: 403 (1941) [≡ Hieracium sanctum L., Cent. Pl. II: 30 (1756), basiónimo] (Compositae, Cichorieae). La designación del correspondiente tipo está basada en la consulta del material original de Linneo y la bibliografía citada en el respectivo protólogo. El material original conservado en LINN (Herbario de Linneo en la Sociedad Linneana de Londres) es designado como el lectótipo.