ABSTRACT
The cocoa and chocolate production chain involves US$60 billion annually and three million farmers around the world, in an area exceeding nine million hectares. The use of wild germplasm will enable to generate new disease- and pest-resistant cultivars and ability to adapt to changing environments. Here we evaluated 145 cocoa accessions, originated from nine Amazonian basins, based on eight fruit traits. Univariate anova showed significant differences (p<0.05) for all traits. For seven traits, the variance component within basins was higher (81.5%, on average). Therefore, it is recommended that the collection of wild accessions prioritize a larger number of plants from a few populations of the most divergent basins. The multivariate analyses revealed a greater divergence between the Ji-Paraná-RO and Solimões/Amazonas-PA basins (27.69) and a greater similarity between Alien clones-PER and Solimões/Amazonas-AM (0.66) in relation to their populations. They also revealed that the accessions differentiation occurred according to the river basin system. These results allowed elucidate the genetic structure and distribution of cacao populations. In addition, strengthen the importance of collecting and conserving germplasm to preserve genetic resources.
Subject(s)
Genetic Variation , Cacao , Hydrographic Basins , Amazonian Ecosystem , Seed BankABSTRACT
Abstract Selecting a representative core collection (CC) is a proven and effective strategy for overcoming the expenses and difficulties of managing genetic resources in gene banks around the globe. Because of the diverse applications available for these sub-collections, several algorithms have been successfully implemented to construct them based on genotypic, phenotypic, passport or geographic data (either by individual datasets or by consensus). However, to the best of our knowledge, no single comprehensive datasets has been properly explored to date. Thus, researchers evaluate multiple datasets in order to construct representative CCs; this can be quite difficult, but one feasible solution for such an evaluation is to manage all available data as one discrete signal, which allows signal processing tools (SPTs) to be implemented during data analysis. In this research, we present a proof- of-concept study that shows the possibility of mapping to a discrete signal any type of data available from genetic resource collections in order to take advantage of SPTs for the construction of CCs that adequately represent the diversity of two crops. This method is referred to as 'SPT selection.' All available information for each element of the tested collections was analysed under this perspective and compared when possible, with one of the most used algorithms for CC selection. Genotype-only SPT selection did not prove as effective as standard CC selection did not prove as effective as standard CC selection algorithms; however, the SPT approach can consider genotype alongside other types of information, which results in well-represented Ccs that consider both the genotype and agromorphological diversities present in original collections. Furthermore, SPT-based analysis can evaluate all available data both in a comprehensive manner and under different perspective, and despite its limitations, the analysis renders satisfactory results. Thus, SPT-based algorithms for CC selection can be valuable in the field of genetic resources research, management and exploitation.
Resumen La selección de una colección núcleo (core-collection) representativa (CC) es una estrategia comprobada y eficaz para superar los gastos y las dificultades de la gestión de los recursos genéticos en los bancos de germoplasma de todo el mundo. Debido a las diversas aplicaciones disponibles para estas subcolecciones, se han implementado con éxito varios algoritmos para construirlos en base a datos genotípicos, fenotípicos, de pasaporte o geográficos (ya sea por conjuntos de datos individuales o por consenso). Sin embargo, hasta donde tenemos conocimiento, no se han explorado adecuadamente conjuntos de datos integrales hasta la fecha. Por lo tanto, los investigadores evalúan conjuntos de datos múltiples para construir CCs representativos; esto puede ser bastante difícil, pero una solución factible para tal evaluación es administrar todos los datos disponibles como una señal discreta, que permite implementar herramientas de procesamiento de señal (SPT) durante el análisis de datos. En esta investigación, presentamos un estudio de prueba de concepto que muestra la posibilidad de asignar a una señal discreta cualquier tipo de datos disponibles de colecciones de recursos genéticos para aprovechar los SPT para la construcción de CC que representen adecuadamente la diversidad de dos cultivos. Este método se conoce como "selección de SPT." Toda la información disponible para cada elemento de las colecciones analizadas se analizó bajo esta perspectiva y se comparó cuando fue posible, con uno de los algoritmos más utilizados para la selección de CC. La selección de SPT de solo genotipo no resultó tan efectiva como los algoritmos de selección de CC estándar; sin embargo, el enfoque SPT puede considerar el genotipo junto con otros tipos de información, lo que da como resultado CCs bien representados que consideran tanto el genotipo como las diversidades agromorfológicas presentes en las colecciones originales. Además, el análisis basado en SPT puede evaluar todos los datos disponibles, tanto de manera integral y bajo diferentes perspectivas, y a pesar de sus limitaciones, el análisis arroja resultados satisfactorios. Por lo tanto, los algoritmos basados en SPT para la selección de CC pueden ser valiosos en el campo de la investigación, gestión y explotación de recursos genéticos.
ABSTRACT
OBJECTIVE: To establish a genebank for phage single-chain antibody for further screening the specificity of single chain fragment variable( Sc Fv) in lung tissue of silicosis rats by phage display technology. METHODS: Twenty-four specific pathogen free male SD rats were used to construct silicosis model by one-time bronchial perfusion with 1. 0 m L of silicon dioxide suspension( mass concentration,100 g / L). We took periphery blood from 6 rats 3,6,9 and 12 weeks respectively after establishing the model. The peripheral lymphocytes were mixed,and total RNA was extracted using Trizol,and c DNA was synthesized by reverse transcription. The degenerated primers were used to amplify the variable region of heavy chain( VH) gene and variable region of light chain( VL) gene by polymerase chain reaction( PCR).Then VH and VL genes were assembled to form Sc Fv by T4 DNA linker. The cloning recombinant of Sc Fv and plasmid of PCANTAB-5e were transformed into competence E. coli TG1 by calcium chloride. The Sc Fv genebank of silicosis model was constructed by M13K07 helper phage superinfection. There were 10 bacterial colonies for plasmid restriction dualenzyme digestion randomly selected for confirmation. RESULTS: Agarose gel electrophoresis showed that there were two bands of obvious 28 S and 18 S in total RNA of periphery blood lymphocytes of silicosis rats. The total RNA was intact. The size of VH gene fragment was about 400 bp,the size of VL gene fragment was about 350 bp and recombinant Sc Fv gene fragment length was about 750 bp. The helper phage was amplified and placed with double-deck agar plate and observed limpid plaque with the size of a rice grain. The phage titer was 1. 35 × 10~(16) pfu / L. The recombinant plasmids were transformed into E. coli TG1 and total bacterial count was 8. 0 × 10~9 cfu / L in resistant plate. The positive cloned plasmid PCR gel electrophoresis and double enzyme results showed a positive inserting rate of 90. 0%. The capacity of phage single-chain antibody genebank of experimental silicosis was 7. 2 × 10~9 cfu / L. CONCLUSION: The silicosis rat model with phage Sc Fv gnebank could be successfully established,and its capacity and diversity provide support for the follow-up screening.
ABSTRACT
Entre as espécies do gênero Passiflora, a P. foetida L. apresenta a maior variabilidade genética e tem grande importância medicinal, pois é usada no tratamento de doenças como asma, icterícia, e na forma de emplastros, para as erisipelas e doenças de pele com inflamação. Portanto, são necessários estudos que visem a micropropagação e conservação. As sementes de P. foetida L. apresentam dormência e muitas vezes, levam alguns meses para germinar, produzindo mudas desuniformes e de baixo vigor. Neste sentido, a cultura de tecidos apresenta-se como uma forma alternativa a propagação. Assim, o objetivo do trabalho foi estabelecer e micropropagar P. foetida L., para formação de um banco de germoplasma. Para tanto, sementes foram escarificadas, desinfestadas e inoculadas em meio MS(½) sem reguladores de crescimento e cultivados por 66 dias. Explantes de hipocótilos obtidos de plantas germinadas in vitro, foram cultivados no mesmo meio suplementado com 1,0 mg L-1 de BAP. Na fase de estabelecimento, 45% dos explantes brotaram e formaram gemas axilares. 88,9% dos explantes de hipocótilo induziram brotação e 11,1% produziram calos. Plântulas regeneradas com 1,82 cm de altura, com raízes foram aclimatadas.
Among the species of the genus Passiflora, P. foetida L. presents highest genetic variability and also great medicinal importance. This species is used in the treatment of diseases such as asthma, jaundice, and in the form of poultices for erysipelas and skin diseases with inflammation. Therefore, studies are needed to preserve them. Its seeds present dormancy and often take several months to germinate. The tissue culture is a alternative form to propagate species. The objective was to establish and micropropagation P. foetida L., and create a germplasm bank. Seeds were scarified, disinfected, and inoculated on MS medium (½) without regulators for 66 days. Hypocotyls explants obtained of seedlings in vitro germinated were transferred and placed in the same medium supplemented with BAP (1,0 mg L-1). In the establishment phase of 45% of the explants sprouted and formed axillary buds. 88,9% of hypocotyl explants induced shoots and 11,1% produced callus. Seedling measuring 1,82 cm length and rooted were acclimatized.