No abstract

Lippia graveolens, commonly known as Mexican oregano, is an aromatic plant of great industrial, nutritional, and medicinal value, principally for its essential oils. Regeneration via axillary buds was established in MS medium supplemented with 6-benzyladenine (BA) (0.5 mgL−1) as a growth regulator. Three genotypes and three stages of cultivation were considered in the study. On average, 3.5, 4.2, and 6.4 shoots induced per explant were obtained for genotypes B, C, and D, respectively. Several doses (0.1, 0.3, and 0.5%) of ethyl methane sulfonate (EMS) and different exposure times (1, 2, and 3 h) were applied to investigate the effect of the chemical mutagen on the formation of axillary buds. Genetic variation among the collected plants, the micro-propagated plants during three sub-cultivations, and the plants regenerated in the presence of the mutagen was evaluated by means of randomly amplified microsatellite polymorphism (RAMP) markers. A high genetic stability was observed in the micro-propagation of Mexican oregano for the three genotypes and three sub-cultivations, presenting 100% of monomorphic bands. The genetic variation observed in the different collections of wild populations (A, R, and V) and after treatment with EMS regarded 34 and 35% of polymorphic loci, respectively.

Evaluation of the essential oil of Lippia graveolens as a growth inhibitor ofSalmonella sp, E. coli and Enterococcus sp.

For the first time, nuclear microsatellite (nSSRs) primers were developed in the endangered tree species Lecythis ampla (Lecythidaceae) as molecular tools. An enrichment protocol with genomic DNA libraries for nSSRs was used to identify candidate loci. A large number of candidate loci were identified. Consecutively population genetic parameters of these loci were tested in two available populations. Eventually 17 microsatellite loci have been identified that show no or only low evidence for linkage disequilibrium, deviations from Hardy-Weinberg expectations or high levels of null alleles. These markers are apt for future molecular population studies.