New insights into the intraspecific cytoplasmic DNA diversity,maternal lineages classification and conservation issues of Tunisian pearl millet landraces

Tunisian pearl millet (Pennisetum glaucum L.) landraces are still growing in contrasting agro-ecological environments and are considered potentially useful for national and international breeders. Despite its genetic potential, the cropping areas of this species are still limited and scattered which increases the risk of genetic erosion. The chloroplast DNA polymorphism and maternal lineages classification of forty nine pearl millet landraces representing seven populations covering the main distribution area of this crop in Tunisia were undertaken based on informative cpSSR molecular markers. A total of 21 alleles combining to 9 haplotypes were detected with a mean value of 3.5 alleles per locus and a haplotype genetic diversity (Hd) of 0.82. The number of chloroplast haplotypes per population ranged from 1 to 4 with an average of 1.28. The haplotypes median-joining network and UPGMA analyses revealed two probable ancestral maternal lineages with a differential pearl millet seed-exchange rate between the investigated areas. Northern and Central populations presented unique genetic backgrounds while historical farmers’ practices in the South-East area resulted in the isolation of their own local landraces. The genetic evidences strongly support at least two introduction origins of pearl millet in Tunisia, one in the North and the other in the South followed by distinct local dispersal histories. Complementary in-situ and ex-situ conservation strategies taking into account the conservation of the maternal lineage cytoplasmic diversity are required. The investigated chloroplast SSRs provide useful molecular markers which could be used in further genetic studies and breeding surveys of pearl millet genetic resources.     

Hammondia hammondi organelle proteins are recognized by monoclonal antibodies directed against organelles of Toxoplasma gondii.

Hammondia hammondi and Toxoplasma gondii, 2 closely related coccidia of cats, are known to share many antigenic molecules as shown by serologic cross reactivity. Monoclonal antibodies (MAbs) directed against the internal organelles of Toxoplasma gondii were tested by immunofluorescence assay and immunoelectron microscopy on the tachyzoites of H. hammondi. The MAbs anti-apex, anti-dense granules, anti-micronemes, and anti-rhoptries recognized, although weakly, the corresponding antigens on H. hammondi. This finding demonstrates that organelles of the 2 parasites are not only morphologically, but also antigenically, similar.     

Polyphenols,flavonoids, antioxidant activity in leaves and flowers of Tunisian Globularia alypum L. (Globulariaceae)

Leaves and flowers from Tunisian Globularia alypum were assessed for their phenolic and flavonoid contents and antioxidant activity. Phenolic (15.5–22.30 mg GAE g^?1 DW) and flavonoid (3.63–4.72 mg RE g^?1 DW) contents varied according to plant part. Globularia alypum leaves exhibited the highest phenol and flavonoid contents, and displayed the highest antioxidant activity, based on radical‐scavenging activity (295 μmol TEAC g^?1 DW) and ferric reducing power (24.27 mmol Fe2+/l). The obtained results demonstrated that some of the isolated compounds play an important role for the antioxidant activity of G. alypum and give a scientific basis to the use of this plant in traditional medicine. The methanolic extract of G. alypum could be considered as a source of potential antioxidants and will promote the reasonable usage of this plant in food technology and processing as well as for medical use.