Some germplasm collections have a high number of accessions, which makes it difficult to explore the genetic variability present in the germplasm bank due to the redundancy and the difficulty of detailed analysis of all conserved accessions. Therefore, our study aimed to analyze the genetic diversity of 153 lima bean (Phaseolus lunatus) accessions for the purpose of constructing a core collection. Eleven SSRs were used for this purpose. The 153 lima bean accessions can be represented by low redundancy using a minimum of 34 accessions, thus representing 22 % of the size of the entire germplasm bank. The core collection had a higher Shannon diversity index and expected heterozygosity (1.906 and 0.811, respectively) than those presented by the entire germplasm bank (1.605 and 0.713, respectively), indicating a higher polymorphism of the representative cultivars in relation to the entire collection. The accessions selected for the core collection may be used in future studies of genome association as well as in genetic crosses in breeding programs aimed at developing improved cultivars with high genetic diversity which can meet current and future market needs.

The knowledge of genetic diversity in plant population is essential to the success of plant breeding programs. Thus, previous characterization of landraces is one of the first steps before the indication of genotypes to these plant breeding programs. This study aimed to characterize, through morphological traits, and estimate the genetic diversity in landraces of lima bean (Phaseolus lunatus L.). Genetic diversity was estimated by using multivariate methods that selected individual landraces to be indicated for farmers and consumers. According to morphological traits proposed by Biodiversity International, the genotypes UFPI-667 and UFPI- 682 showed higher dissimilarity and high potential to be used in crosses since they are genetically distant and complementary. The principal component analysis identified positive and significant phenotypic associations between variables: pod length, pod width, and grain production. According to the multivariate methods used, the landraces UFPI-666, UFPI-650, UFPI-651, UFPI-687, UFPI-658, UFPI-673, UFPI-667, and UFPI-674 are potential candidates for selection since they have relevant features for lima bean breeding, such as shorter cycles and higher grain production. This study showed that multivariate analysis can be used as an effective tool to find potential traits in lima bean and can assist the lima bean breeders in the selection of potential landraces. Accessions UFPI-667 and UFPI-682 can be indicated as genitors for breeding programs, as they are genetically distant and complementary in their characteristics.

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The aim of this study was to characterize and estimate genetic divergence among twelve specimens of the Sansevieria genus from the collection of the Universidade Federal do Piauí (UFPI). A completely randomized experimental design was used with three replicates, and the plot consisted of four plants. In morphological characterization, qualitative and quantitative descriptors of leaves were evaluated. Genetic divergence among the specimens was determined by the Tocher clustering method and the hierarchical UPGMA. There is genetic variation among specimens evaluated, which was also expressed by the variability of colors, shapes, and sizes of the leaves. The Tocher clustering method and the hierarchical UPGMA were effective in differentiation of the specimens from multi-categorical qualitative descriptors, as the Tocher method grouped the accessions in two groups and the UPGMA in seven different groups. We highlight the accessions SSV 09 and SSV 10 as exhibiting the highest mean values in weekly leaf growth and in leaf height, important characteristics for local sale and for export.

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O presente estudo tem como objetivo compreender a importância do aplicativo Bio V para a melhoria do ensino de botânica nas escolas do campo. Este aplicativo foi elaborado de forma a possibilitar a compreensão dos conceitos botânicos aos alunos das escolas do campo. Trata-se de uma pesquisa qualitativa que descreve o processo de elaboração e avaliação do uso do aplicativo Bio V com dez profissionais da Educação Básica do município de Floriano-Piauí, que atuam em escolas do campo. O Bio V foi avaliado positivamente pela maioria dos participantes, sendo um instrumento facilitador do processo de ensino e aprendizagem. Os dados afirmam a importância do desenvolvimento de ferramentas tecnológicas que aproximem os alunos dos conteúdos de forma dinâmica, objetiva e interativa. Dessa forma, o estudo é de grande relevância para o ensino de botânica, sobremodo, para o fortalecimento da Educação do Campo.

ABSTRACT. Mangabeira (Hancornia speciosa) is a native fruit tree found mainly in the Cerrado biome and shows great economic potential due to its multiple uses; the fruits are used in agriculture, are important as a food resource, and can be consumed in natura or processed. Due to a reduction in the area of ecosystems where it occurs, mangabeira is threatened by genetic erosion in Brazil. The characterization of the genetic diversity of plants can provide the basis for strategies to protect and conserve endangered populations, like mangabeira. This study aimed to compare eight DNA extraction methods in mangabeira because the key to success is the use of a pure genomic DNA for the characterization of genetic diversity in molecular biology techniques. The quality and concentration of DNA were revealed by agarose gel electrophoresis. Polymerase chain reaction amplifications were successfully by extractions using two commercial purification kits and by the method proposed by Khanuja et al. (1999), which produced sufficient genomic DNA of good quality from leaves of H. speciosa to perform techniques involving molecular biology. The protocol described by Khanuja et al. (1999) is less expensive when compared to the commercial purification kits.

Anacardium occidentale (cashew) is a tropical tree species that occurs mainly in northeastern Brazil. The species has great socioeconomic importance for rural populations. We investigated the genetic diversity of a natural cashew population in a rural area of Floriano, State of Piauí, Brazil. We quantitatively evaluated 12 natural variables related to the inflorescence, the cashew nut (fruit), and the peduncle (pseudofruit) in 35 trees (numbered sequentially G1-35). The characteristics of the peduncle (pseudofruit) appeared as the variables that most contributed to genetic divergence, while characteristics related to the inflorescence contributed less to the morphological differentiation. Multivariate statistics, employing principal component analysis evidenced that the first three principal components explained 81.72% of the total variance. Cashews G-3 ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 18 (3): gmr18348 L.A. Carneiro et al. 2 and G-8 were identified as the most divergent, with G-3 demonstrating the greatest peduncle lengths and weights.