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The bacterial endophytic communities residing within roots of maize (Zea mays L.) plants cultivated by a sustainable management in soils from the Quechua maize belt (Peruvian Andes) were examined using tags pyrosequencing spanning the V4 and V5 hypervariable regions of the 16S rRNA. Across four replicate libraries, two corresponding to sequences of endophytic bacteria from long time maize-cultivated soils and the other two obtained from fallow soils, 793 bacterial sequences were found that grouped into 188 bacterial operational taxonomic units (OTUs, 97% genetic similarity). The numbers of OTUs in the libraries from the maize-cultivated soils were significantly higher than those found in the libraries from fallow soils. A mean of 30 genera were found in the fallow soil libraries and 47 were in those from the maize-cultivated soils. Both alpha and beta diversity indexes showed clear differences between bacterial endophytic populations from plants with different soil cultivation history and that the soils cultivated for long time requires a higher diversity of endophytes. The number of sequences corresponding to main genera Sphingomonas, Herbaspirillum, Bradyrhizobium and Methylophilus in the maize-cultivated libraries were statistically more abundant than those from the fallow soils. Sequences of genera Dyella and Sreptococcus were significantly more abundant in the libraries from the fallow soils. Relative abundance of genera Burkholderia, candidatus Glomeribacter, Staphylococcus, Variovorax, Bacillus and Chitinophaga were similar among libraries. A canonical correspondence analysis of the relative abundance of the main genera showed that the four libraries distributed in two clearly separated groups. Our results suggest that cultivation history is an important driver of endophytic colonization of maize and that after a long time of cultivation of the soil the maize plants need to increase the richness of the bacterial endophytes communities., This study was supported by ERDF-cofinanced grant PE2012-AGR1968 from Consejería de Economía, Innovación y Ciencia (Junta de Andalucía, Spain) and the CSIC-sponsored I-COOP Agrofood project 2014CD0013.

En este artículo realizamos un estudio arqueológico sobre los guancas y taramas pre-Tawantinsuyo, en el cual analizamos sus aspectos económicos y sociales. En el marco de esta investigación nos enfocamos en estudiar el desarrollo agrícola y ganadero de estas culturas en relación a los Andes centrales y también analizamos la organización social de estas culturas. Todo esto en base a los datos arqueológicos que registramos durante nuestras prospecciones y excavaciones arqueológicas. En este trabajo exponemos nuestras teorías sobre el desarrollo económico y social de los guancas y taramas, las cuales formulamos en base a nuestros datos arqueológicos; dentro de este punto también realizamos unas críticas hacia las teorías que propusieron Upper Mantaro Research Project (UMARP) y Parsons para explicar la organización social y economía de los guancas y taramas respectivamente. Además realizamos un breve estudio sobre la actividad funeraria Guanca y Tarama, el cual ha sido un tema poco estudiado hasta el momento., In this paper we carry out a comprehensive archaeological study on the Pre-Tawantinsuyo guancas and taramas, focusing on their economic and social development. For this purpose, we performed methodical archaeological surveys and excavations, which gave us much empirical evidence. The description and analysis of this data helped us to better understand these cultures in relation to the Central Andes. Therefore, on this basis, we propose new theories that better explain the economic and social development of Guancas and taramas, likewise, we present a critique of the theories previously proposed by Parsons and the Upper Mantaro Research Project (UMARP). Furthermore, in this paper, we conduct a brief study on the funerary activities of the Guanca and Tarama, a subject little studied so far.