Biomass production and nutritional properties of promising genotypes of Tithonia diversifolia (Hemsl.) A. Gray under different environments

Abstract

Tithonia diversifolia is a shrub with excellent forage characteristics that has shown a wide genetic and phenotypic diversity. The objective of this study was to determine the biomass production and nutritional quality of seven genotypes of T. diversifolia with outstanding characteristics for ruminant nutrition, to analyze the Genotype x Environment (GxE) interaction of biomass production and to compare the performance of these genotypes with grasses offered normally in tropical conditions. For the GxE interaction the AMMI and SREG models were used, and evaluations were made in three environments. In the GxE analysis, the interaction was significant and effects of the environment on biomass productivity were observed with differences between genotypes (p <0.05). In the three environments, the chemical composition was adequate to be offered to ruminants. It is worth noting the high content of crude protein (28.89 g/100 g of dry matter - DM), the low fiber content (30.95 g of neutral detergent fiber - NDF/100 g of DM) and the high percentages of in vitrodegradation of DM for all the genotypes. It is possible to conclude that there are superior genotypes of T. diversifolia with the ability to have good productive and adaptive performance for high-altitude and low-altitude zones with low fertility soils.