Coleta, caracterização, avaliação e seleção em germoplasma de pimenta-de-macaco (Piper aduncum L.)

Abstract

Spiked pepper (P. aduncum L.) possess highter yielding of essential oil of proved activity against harmful microrganisms for the agriculture and human health. The aim was to collect, to characterize, to evaluate and to select genotypes toward cropping in amazonian agroecossystems. Were collected vegetative materials (leaves, thin branches and stake) of 42 parentals in 10 provenances of Brazilian Amazon of five physiographic regions. Were utilized 14 morphoagronomic traits: number of leaves per branch; length of the leaf; width of the leaf; diameter of the older branch; height of the plant; number of orthotropic branches, number of plageotropic branches, length of the internode; number of spikes per branch; yielding of essential oil; content of dilapiol; production of dilapiol; weight o f the fresh matter and weight of the dry matter; and, RAPD, as molecular markers. At the morphoagronomic traits, were applied descriptive, parametric and principal component analysis. At the molecular markers, were employed cluster analysis to estimate the genetic similarity by mean of group. The parentals showed adaptability one diversity of ecological and edaphoclimatical conditions, that too was verified in 13 experimentally cropped clones, confirming the expectancy that your adaptability will easy your domestication and cropping; the morphologic traits that more expressed variability were number of orthotropic branches and diameter of older branch (parentals), which, in experimental conditions, presented tendency to manifest variability with the growth of the plants; the agronomic traits that more expressed variability were the content and the production of dilapiole (parentals) and, among the evaluated clones, the environmental shifting favored large production of dry matter, essential oil and content of dilapiole. The three first principal components explicated 46.8% on the variation of the traits, being variance diluted in the components and 83.33% on the traits discriminated variability the genotypes. It was suggested for discarding the yielding of essential oil and the number of leaves per branch. The tridimensional graphic dispersion showed a relatively homogeneous and continuous clustering. The genetic similarity evidenced the variability among origins, being probably that your patterns follow that of geographic distribution, no more there was the tendency of accessions of even origin constituted same cluster. It was concluded that the easiness of adaptation edaphoclimatical and ecological diverse conditions of the parentals from Manaus-AM favored adaptation of primary clones in conditions of cropping, in Belem-PA, Brazil; the variability of parentals from Manaus-AM, Brazil tended to express itself in the cropped clones throughout the growth of plants, with clones revealing themselves promising for cropping toward small trade production and; the estimated yielding of essential oil and content of dilapiole in experimental conditions, in the ecological and edaphoclimatical conditions from Belem-PA, Brazil, were larger the estimated in natural conditions of Manaus -AM, Brazil (parentals). Ten morphoagronomic traits possess discriminatory variability of the genotypes and the similarity presented wide range of variability (29% at 85%). It was proved divergent genotypes as by morphoagronomic traits as molecular markers, being that the lasts seemed to have major discriminatory power, with one minor number of analysed genotypes.