BIOLOGICAL BEHAVIOR OF SIX CULTIVARS OF Tithonia diversifolia (Helms.) A. Gray

Background: Climate change, anthropic factor and non-compliance with livestock technologies are factors that modify ecosystems and biodiversity, which leads to the adoption of productive alternatives based on shrub species. Objective: To evaluate the biological behavior of six cultivars of Tithonia diversifolia (Helms.) A. Gray in three localities of the Manabí province, Ecuador. Methodology: The cultivars were obtained from the Vegetable Program of the National University of Colombia, establishing themselves in the localities: El Carmen, Canuto and San Antonio. The plant structure and physiological morpho evaluations were developed every 90 days for one year under a divided plot design with four repetitions. Results: The principal component analysis (PCA) with the formation of three components managed to determine 70.53% of the accumulated variance explained. The analysis of variance yielded, depending on the interaction, that the San Antonio locality in the rainy period was the one that allowed expressing the potential of the cultivars (1-3 and 13-5) as a function of height, number of shoots and leaves. dead, (all except 1-2), while forage yield was not affected by the third degree interaction, if not, by the combination of locality x cultivars, where the best expression (P≤0.001) was obtained in the locality El Carmen with cultivar 13-5. Implications: This is the first report about the cultivation and evaluation of cultivars of T. diversifolia in the coastal zone of Ecuador, considering as expectations, assess the expression of the nutritional value in the edaphoclimatic conditions in which they grew, and explore about the services ecosystems that this plant offers in production systems. Conclusions: There was a differentiated response for each cultivars in the variables studied, some (1-3 and 13-5) showed an attitude towards the growth, development and production of biomass, favored by the climatic conditions of the towns of El Carmen and Canuto. While others (1-2) showed a poor performance in all the factor relationships considered. In the San Antonio locality the lowest values of most of the variables under study were concentrated, affecting the accumulation of biomass.