RESUMO
Capsicum spp. members are a rich source of specialized compounds due to their secondary metabolism. Some metabolic pathways have suffered modifications during the domestication process and improvement of agricultural traits. Here, we compared non-targeted LC-MS profiles from several areas: wild accessions (C. annuum L. var. glabriusculum), domesticated cultivars (C. annuum L.), and the F1 progeny of a domesticated, and a wild accession cross (in both directions) throughout seven stages of fruit development of chili pepper fruits. The main detected differences were in glycerophospholipid metabolism, flavone and flavonol biosynthesis, sphingolipid metabolism, and cutin biosynthesis. The domesticated group exhibited a higher abundance in 12'-apo-ß-carotenal, among others capsorubin, and ß-tocopherol. Palmitic acid and derivates, terpenoids, and quercitrin were prevalent in the wild accessions. F1 progeny showed a higher abundance of capsaicin, glycol stearate, and soyacerebroside I. This work supports evidence of the side-affectation of trait selection over the metabolism of chili pepper fruit development. Furthermore, it was also observed that there was a possible heterosis effect over the secondary metabolism in the F1 progeny.
RESUMO
The domestication syndrome of many plants includes changes in their mating systems. The evolution of the latter is shaped by ecological and genetic factors that are particular to an area. Thus, the reproductive biology of wild relatives must be studied in their natural distribution to understand the mating system of a crop species as a whole. Gossypium hirsutum (upland cotton) includes both domesticated varieties and wild populations of the same species. Most studies on mating systems describe cultivated cotton as self-pollinated, while studies on pollen dispersal report outcrossing; however, the mating system of upland cotton has not been described as mixed and little is known about its wild relatives. In this study we selected two wild metapopulations for comparison with domesticated plants and one metapopulation with evidence of recent gene flow between wild relatives and the crop to evaluate the mating system of cotton's wild-to-domesticated complex. Using classic reproductive biology methods, our data demonstrate that upland cotton presents a mixed mating system throughout the complex. Given cotton's capacity for outcrossing, differences caused by the domestication process in cultivated individuals can have consequences for its wild relatives. This characterization of the diversity of the wild relatives in their natural distribution, as well as their interactions with the crop, will be useful to design and implement adequate strategies for conservation and biosecurity.
RESUMO
Population genetics of Colombian Guinea Pigs, Cavia spp. (Rodentia: Caviidae) with RAPD molecular markers. The genus Cavia occurs in South America, mainly in grasslands.. We collected blood samples from 97 individuals in six field populations and analyzed them with RAPD molecular markers. One wild type (C. anolaimae) was differentiated from the domestic form (C. porcellus), in agreement with other authors who used morphological, osteological and karyotipic results. Genetic diversity was considerable in both species, but higher in C. porcellus. The levels of genetic heterogeneity were also higher among the populations of C. porcellus (F ST = 0.254) than among the populations of C. anolaimae (F ST = 0.118). These significant levels of genetic heterogeneity, and the low levels of gene flow, were consistent with a complex domestication process for Cavia porcellus. Rev. Biol. Trop. 56 (3): 1481-1501. Epub 2008 September 30.
En el presente estudio, mostramos los primeros resultados moleculares de formas colombianas de Cavia. Claramente, la población silvestre de C. anolaimae fue genéticamente diferenciada de la forma doméstica, C. porcellus, tal como ha sido demostrado por otros autores utilizando resultados morfométricos, osteológicos y cariotípicos. Ambas especies mostraron un considerable nivel de diversidad genética, aunque el segundo taxon mostró niveles mayores de esta diversidad. Los niveles de heterogeneidad genética también fueron mayores entre las poblaciones de C. porcellus (F ST = 0.254) que entre las poblaciones de C. anolaimae (F ST = 0.118). Esos niveles significativos de heterogeneidad genética, y los consiguientes bajos niveles de flujo génico, fueron discutidos comparativamente con los resultados por otros autores analizando otros marcadores moleculares (citocromo-b mitocondrial). Los resultados aquí mostrados son coherentes con un complejo proceso de domesticación en Cavia porcellus.