Studies on genetic diversity and genetic structure of natural populations are important in order to define strategies for in situ and ex situ conservation actions and for plant pre-breeding programs. Aiming to assess the genetic diversity and genetic structure of three wild American Oryza species with isozyme markers, 14 populations of the diploid O. glumaepatula (A gl A gl ), 11 populations of the tetraploid O. grandiglumis (CCDD) and five populations of the also tetraploid O. latifolia (CCDD) were studied. They were all originated from Rio Paraguay hydrographic basin and the Amazon. Four enzymes were used and they gave 40 polymorphic bands. The most polymorphic species was O. glumaepatula, followed by O. latifolia and O. grandiglumis. A cluster analysis with the Jaccard similarity coefficient separated the diploid from the two tetraploid species, and also the two tetraploid species. This separation was also evident on a scatter plot from a principal component analysis, suggesting that they should be treated as two separate species, although further studies are necessary to provide support for this affirmative. The AMOVA analyses showed a high intrapopulational variability for O. latifolia (67.6%) and O. grandiglumis (52.2%), when compared to their interpopulational variability (32.4% and 47.8%, respectively), which suggests the hypothesis of a higher degree of outcrossing events within these species. When studying the correlation between the Jaccard dissimilarity coefficient and geographic distances, a spatial genetic structure was observed for O. glumaepatula only. These results are important for defining strategies of both in situ and ex situ conservation.

There are many procedures for obtaining minimally processed fruits and vegetables, aiming at adding value and maintaining the quality for a longer period. Cassava is a root that adapts to minimum processing technology, because the tissues are more resistant, what helps in obtaining different cut shapes and formats. However, it is a root susceptible to browning and microbiological contamination. In this chapter, methodologies and procedures are described to obtain alternative formats for minimally processed cassava, which was generally denominated "babycassava",called"babytolete", "cateto",and "rubiene". Besides that, some preharvest and postharvest factors that influence the shape and quality of "babycassava" formats will be addressed. It was verified that preharvest factors could influence the quantitative and qualitative aspects, resulting in browning of the minimally processed root. Some of the factors studied seem to regulate key enzymes in which they mediate oxidative reactions that cause browning, such as polyphenol oxidase and peroxidase, and other enzymes that participate in the reactive oxygen species (ROS) elimination process. In this way, the turning stage of "babycassava" manufacturing removes the parenchyma, minimizing the effect of browning-related enzymes.

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O município de Vitória do Xingu, no estado do Pará, apresentou rebanho bovino de cerca de 150 mil cabeças em 2019, evidenciando o potencial produtivo da região. Como subsídio para a expansão da atividade pecuária é necessário o desenvolvimento de estudos que visem à manutenção da qualidade do solo nos sistemas de produção, subsidiando alternativas de manejo. O objetivo do trabalho foi analisar os parâmetros físico-químicos do solo, considerando o período climático (chuvoso e seco) e a profundidade (0-20 e 20-40 cm), em uma propriedade particular, localizada no município de Vitória do Xingu, estado do Pará. Foram adotados três tratamentos, sendo T1 (vegetação secundária), T2 (pastagens de 10 anos) e T3 (pastagem de 30 anos). Para a análise estatística dos atributos foi utilizado o teste não-paramétrico de Wilcoxon (P<0,05). Todos os solos foram classificados com textura média. A densidade do solo foi maior em T3 e T2. A densidade de partículas foi maior em T1, seguido por T2 e T3. As áreas de pastagem apresentaram melhores condições de fertilidade que T1. O resultado do teste de Wilcoxon demonstrou que na camada superficial (0-20 cm), houve diferenças significativas entre os atributos analisados, sendo tais diferenças mais evidentes no período chuvoso. Os atributos diferiram na camada superficial de T1 em razão do período climático. O mesmo ocorreu com a camada subsuperficial de T3. A pastagem com 30 anos mostrou-se em maior estádio de degradação que as demais, sendo necessária a intervenção voltada para melhoria dos pastos, de modo a contribuir no potencial produtivo e de recuperação de pastagens na propriedade rural.