The aim of the study was to evaluate the antifungal activity of extracts of 10 plant species used in traditional Uruguayan medicine against the phytopathogenic fungus Alternaria spp. The plants were selected on the basis of their reported ethnobotanical uses. Aqueous, saline buffer and acid extracts of different plant species were screened in vitro for their antifungal activity against Alternaria spp. For the antifungal evaluation we used a microspectrophotometric assay. Minimal inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of the extracts were determined. Three solvents were assayed on different tissues of the plants and among the 29 evaluated extracts, 31% of the extracts inhibited growth, similar to the effects of a chemical fungicide. Acid extracts of the plants were more effective than the aqueous or buffer extracts against Alternaria spp. The MIC values of the extracts were determined ranging between 1.25 and 25 µg mL -1 . The MFC values of the extracts ranged between 1.25 µg mL -1(Rosmarinus officinalis L.) and 10 µg mL -1 (Cynara scolymus L.). MICs and MFCs values obtained from leaves (Salvia officinalis L. and R. officinalis) and seeds extracts (Salvia sclarea L.) were quite comparable to values obtained with the conventional fungicide captan (2.5 µg mL -1 ). The extracts of Salvia sclarea, S. officinalis and R. officinalis could be considered as potential sources of antifungal compounds for treating diseases in plants. These extracts showed maximum activity, even at very low concentrations, and the same fungicide effects as chemical fungicide. We conclude from this that these extracts exhibit amazing fungicidal properties that support their traditional use as antiseptics.

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D. Alem, R. Narancio, P. Díaz Dellavalle, M. Rebuffo, R. Zarza, and M. Dalla Rizza. 2011. Molecular characterization of cultivars of Lotus corniculatus using transferable microsatellite markers. Cien. Inv. Agr. 38(3): 453-461. Lotus corniculatus L. is the most important agricultural species in the genus Lotus and is the most widely distributed Lotus species worldwide. L. corniculatus genotypes form complex groups that are difficult to recognize both morphologically and biochemically. Given the extensive and expensive process of isolating Simple Sequence Repeats (SSR, also called microsatellites), the possibility of using microsatellites already identified in related species is highly attractive. The aim of this work was the identification and validation of transferable microsatellite markers in L. corniculatus, and using those markers to study the genetic variability among four cultivars. Each cultivar of L. corniculatus was represented by 15 genotypes. Ten microsatellite markers were evaluated, and from those, four were selected based on their discriminative values observed among cultivars. We detected 29 alleles for the four markers, and there was an average of 7.25 alleles per locus. The marker TM0197 had the fewest number of alleles (5) and TM0083 had the highest number of alleles (10). The polymorphic information content (PIC) for the selected markers varied from 0.19 to 0.35, and the markers were therefore classified as highly informative. Based on the markers, we found high variability between individuals of the same cultivar. The use of transferable microsatellite markers could be useful to differentiate individuals at a relatively low cost, showing a great potential for use in breeding programs.

Antimicrobial peptides have been considered a new source of biomolecules in several fields of research/innovative applications: they would adjust to an ideal behavior seeking to overcome clinician, microbiological, human-animal-plant-environmental concerns. Antimicrobial peptides can be considered as ancient weapons found in living organisms suggesting they have played a fundamental role in his successful co-evolution with pathogens. Acting on microorganism membrane or having intracellular targets, they can also act as effectors of the innate immune response resulting on non-specific mechanisms of action. Two elements have speeded the research on pathogen control alternatives: a verified increase of antibiotic resistance and the relevance of finding amenable environmental compounds in plant health. As a result of its importance, great efforts have been accomplished to find, characterize, combine and synthesize effective antimicrobial peptides. This review intends to emphasize the generation of biomolecules, whether native or synthetic analogues, that have been matter of recent patents. Development of biomolecules suitable for therapeutic scopes and agricultural use have several challenges such as intrinsic toxicity, in vivo stability and suitable formulation contemplating the cost of production. Thus, biotechnological procedures using microbial systems or transgenic crops as plant factories might help to solve these challenges.