Canonical correlations in elephant grass for energy purposes

摘要

Elephant grass has the potential to be used as a source for energy production. Besides dry matter yield, other characteristics related to biomass quality are important. The canonic correlation analysis is a multivariate statistical procedure that allows for discovering characteristic associations among groups. The objective of this study was to evaluate the canonic correlation existing between the groups of agronomic traits and biomass traits in elephant-grass genotypes aiming to identify possible associations between the groups of variables in order to use this information in breeding programs of elephant grass for energy. The experiment was conducted at Colégio Estadual Agrícola Ant?nio Sarlo, located in Campos dos Goytacazes, RJ, Brazil. The evaluation cuts were made in June 2009 and February 2011; the first and third evaluation cuts, respectively. In the first cut, the following morpho-agronomic traits were evaluated: dry matter yield, percentage of dry matter, number of tillers, plant height, stem diameter, percentages of ash, cellulose, lignin, acid detergent fiber and crude protein and calorific value. In the third cut, in addition to the morpho-agronomic traits assessed in the first cut, the leaf-blade width and percentages of ash, cellulose, lignin, acid detergent fiber and neutral detergent fiber were also evaluated. The experimental design was of randomized blocks with 40 genotypes. Variance analysis and canonic correlation were performed between the morpho-agronomic and biomass-quality traits for the cuts isolated. A positive correlation was found between the percentage of dry matter and the fiber content and the plant height and number of tillers and the percentage of crude protein.