Influences of plant organ, genotype, and cultivation site on the endophytic bacteriome of maize (Zea mays L.) in the semi-arid region of Pernambuco, Brazil.

Endophytic bacteria play a crucial role in plant development and adaptation, and the knowledge of how endophytic bacteria assemblage is influenced by cultivation site and plant genotype is an important step to achieve microbiome manipulation. This work aimed to study the roots and stems of endophytic bacteriome of four maize genotypes cultivated in two regions of the semi-arid region of Pernambuco - Brazil. Our hypothesis is that the endophytic community assemblage will be influenced by plant genotypes and cultivation region. Metabarcoding sequencing data revealed significant differences in alfa diversity in function of both factors, genotypes, and maize organs. Beta diversity analysis showed that the bacterial communities differ mainly in function of the plant organ. The most abundant genera found in the samples were Leifsonia, Bacillus, Klebsiella, Streptomyces, and Bradyrhizobium. To understand ecological interactions within each compartment, we constructed co-occurrence network for each organ. This analysis revealed important differences in network structure and complexity and suggested that Leifsonia (the main genera found) had distinct ecological roles depending on the plant organ. Our data showed that root endophytic maize bacteria would be influenced by cultivation site, but not by genotype. We believe that, collectively, our data not only characterize the bacteriome associated with this plant and how different factors shape it, but also increase the knowledge to select potential bacteria for bioinoculant production.

Selecão de genótipos de arroz tolerantes à salinidade durante a fase vegetativa / Selection of genotypes of salinity tolerance rice during the vegetative phase

O objetivo deste trabalho foi avaliar o grau de tolerância e sensibilidade à salinidade de genótipos de arroz durante a fase vegetativa da planta. O experimento foi conduzido sob condicões de telado, nas dependências da Empresa Pernambucana de Pesquisa Agropecuária-IPA (Recife-PE), em 1996. Foram avaliados doze genótipos de arroz, sendo dez tolerantes e dois sensíveis à salinidade no estádio de desenvolvimento vegetativo. O delineamento experimental foi em blocos ao acaso com arranjo fatorial (doze genótipos x quatro níveis de NaCl), em três repeticões. Os resultados constataram existência de variabilidade entre os genótipos de arroz na populacão estudada para tolerância e sensibilidade à salinidade. As linhagens PR492, PR504, CNA8250, CNA8262 e CNA8267 são tolerantes e a CNA8270, CNA8258, CNA8269, PR475 e PR477 são sensíveis à salinidade dos solos durante a fase vegetativa.