RESUMO
Our study focuses on the molecular analysis of the genetic diversity within 15 Tunisian durum wheat varieties and the assessment of the efficiency of some available markers to select valuable genotypes for technological proprieties of semolina (i.e. parameters related to SDS-sedimentation, mixing time and breakdown resistance of mixograph, grain protein content and yellow colour). While several markers were validated, others were not informative within the genotypes used. A high level of polymorphic information content (PIC) was detected, with an average of 5.2 polymorph alleles per locus and 0.6 average. Old varieties have high protein content however; modern varieties display strong gluten strength. Our results thus open the opportunity to choose valuable parents on the base of pedigrees, technological properties and genetic distances; and lead us to select efficient markers for the Regional Indigenous Land Strategy (Rils) selection strategy
Nosso estudo enfoca a análise molecular da diversidade genética em 15 variedades de trigo duro tunisiano e a avaliação da eficiência de alguns marcadores disponíveis para selecionar genótipos valiosos para propriedades tecnológicas de semolina (ou seja, parâmetros relacionados à sedimentação sds, tempo de mistura e resistência à degradação do mixógrafo, teor de proteína dos grãos e cor amarela). Enquanto vários marcadores foram validados, outros não foram informativos dentro dos genótipos utilizados. Foi detectado um alto nível de conteúdo de informação polimórfica (pic), com uma média de 5,2 alelos polimórficos por locus e 0,6 média. Variedades antigas têm alto teor de proteína no entanto; variedades modernas exibem forte força de glúten. Nossos resultados abrem, assim, a oportunidade de escolher pais valiosos com base em pedigrees, propriedades tecnológicas e distâncias genéticas; e nos levam a selecionar marcadores eficientes para a estratégia de seleção da estratégia regional de terras indígenas (rils).
Assuntos
Variação Genética , TriticumRESUMO
The chemical composition of essential oils isolated from the leaves of Juniperus oxycedrus by hydrodistillation was analyzed by GC-MS. 42 compounds, representing 96.73% of total oil, were identified. J. oxycedrus oil was found to be rich in α-pinene (39.63%), manoyl oxide (12.34) and z-caryophyllene (4.1%) and characterized by relatively high amounts of monoterpenes hydrocarbons and sesquiterpenes. Results of the antifungal testing by in vitro contact assay showed that the oil significantly inhibit the growth of nine plant pathogenic fungi.
RESUMO
Currently, the use of synthetic chemicals to control weeds raises several concerns related to environment and human health. An alternative is to use natural products that possess good efficacy and are environmentally friendly. Among those, essential oils have been extensively tested to assess their herbicidal properties as valuable natural resource. The essential oils whose phytotoxic activities have been demonstrated, as well as the importance of the synergistic effects among their components are the main focus of this review. Essential oils are volatile mixtures of hydrocarbons with a diversity of functional groups (ketones, ether, ester, alcohol, phenol, aldehyde …) and their herbicidal activity has been linked to the presence of monoterpenes and sesquiterpenes. However, in some cases, these chemicals can work synergistically, improving their effectiveness. Among the plant families with promising essential oils used as herbicide, Lamiaceae, Myrtaceae, Asteraceae and Anacardiaceae are the most cited. Individual compounds present in these mixtures with high activity include α-pinene, limonene, 1,8-cineole, carvacrol, camphor and thymol. Finally, although from an economical point of view synthetic chemicals are still more frequently used as herbicide than essential oils, these natural products have the potential to provide efficient and safer herbicide for humans and the environment.