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Since 1998, new maté trees were identified in five plantations in Misiones, Argentina, through mass selection. Emphasis was put on capturing genes related to caffeine, theobromine, saponin, twig color, anthocyanin, waxiness, leaf chlorophyll, and leaf thickness, characteristics that influence maté leaf quality in the drinking vessel or in the bombilla. Subsequently, saponin content of maté leaves was positively correlated with leaf thickness, anthocyanin, waxiness, and leaf chlorophyll. Saponin content was negatively, though slightly, related to caffeine content. A cluster analysis was used to distinguish the desired quality ideotypes, retaining good variability of the origins among the quality R. Scherer groups. The major consumer categories proposed were Gaucho for traditional consumption, Tango for urban consumption and Middle-East as an alternative for green tea. Seed gardens were organized accordingly to ensure market quality.

We report the first comprehensive multilocus molecular characterization of cultivated Ilex paraguariensis plants belonging to a breeding program. Using nuclear and homologous chloroplastidic molecular markers, we have genotyped 158 plants from four plantation sites. Analyses of the nuclear data (187 variable dominant loci) allowed detecting high diversity (0.569), the occurrence of four distinct genetic clusters, and a low but significant differentiation among sites. Additionally, 20 chloroplastidic alleles were identified applying five microsatellite polymorphic markers, and a high chloroplastidic diversity was recognized (0.505); two haplogroups were distinguished amongst the 63 haplotypes detected. Our results from both nuclear and plastidic markers indicate that most genetic variation reside within plantations sites (≥ 95%), and that these plantations were established on highly variable materials (either as seeds or plantlets) derived from, at least, 63 maternal lineages. Moreover, our study suggests that the genetic structure within each plantation site was most likely shaped by past admixture favored by farmers´ practices during the establishment of each plantation. Also, subsequent constraints in gene flow and/or a low level of shared polymorphism among plantations could have contributed to current structure.

Os microrganismos cavernícolas, principalmente os de litologia ferrífera, são pouco conhecidos. Estes constituem a maior parte da biodiversidade da caverna e desempenham papel fundamental na manutenção do ecossistema cavernícola. O isolamento e a caracterização da microbiota cavernícola podem levar a identificação de novas espécies e a obtenção de substâncias de interesse biotecnológico. O objetivo desse trabalho foi isolar e avaliar as atividades enzimática e antimicrobiana de microrganismos isolados do solo de caverna do Parque Nacional dos Campos Ferruginosos, sudeste amazônico. Foram coletadas amostras de solos da camada superficial interna da caverna GEM-1462 nas diferentes zonas (afótica, disfótica e fótica). Para caracterização das linhagens, utilizou-se a técnica de coloração de Gram e prova bioquímica. Foram avaliadas as atividades proteolíticas, celulolítica, amilolítica, fixação de nitrogênio, solubilização de fosfato e actinomicetos dos microrganismos. A atividade antimicrobiana foi avaliada por meio de ensaio de antibiose, teste de difusão em disco e concentração inibitória mínima contra cepas bacterianas padrão. No total, foram isoladas 10 colônias microbianas distintas e todas apresentaram atividade enzimática, destacando-se a atividade proteolítica. Quatro linhagens microbianas apresentaram atividade antimicrobiana para as cepas Bacillus subtilis e Klebsiella pneumoniae. Este estudo demonstrou a primeira descoberta de atividade biológica dos microrganismos de caverna ferrífera, indicando que a caverna GEM-1462 é uma promissora fonte para prospecção de microrganismos com potencial biotecnológico, principalmente de enzimas proteolíticas.