Factores biológicos que determinan la competencia de Commelina erecta con otras malezas en sistemas de cultivo

AUTOR(ES)
FONTE

Planta Daninha

DATA DE PUBLICAÇÃO

2011-03

RESUMO

Competition of C. erecta from seed and rhizome origin with Digitaria sanguinalis and Amaranthus quitensis was studied. The objectives of the study were: 1) determine growth dynamics of plants of these weed species in binary mixtures and in monocultures; 2) estimate the relative yield of each species (RY) and relative yield total (RYT) of the different mixtures, and 3) to use a dynamic model to analyze the importance of different specific attributes on the result of the competition. The growth of the monoculture of all species fitted to a sigmoidal model. The RY of the different species varied relative to the accompanying species, the sampling date and the year. Competition was partial (RYT > 1) only in mixtures including C. erecta plants originated from rhizomes. From the simulations with the model it was determined that the result of the competition depends on the initial size (BI) of C. erecta rhizomes. Furthermore, the sensibility analysis highlights the importance of the intrinsic growth rate (r) in the definition of RY. Under competition conditions the biological parameters defining the growth of the species studied were particularly r and BI. The results emphasize the complex interaction of the factors determining the competitive balance, between both propagation forms of C. erecta, and between those forms and other weed species.

Documentos Relacionados