Morphogenetic and structural characteristics of forage grasses were evaluated in order to group them according to their pattern of development in their respective functional groups. Grasses were planted in plots of 1.0 m² with 24 plants in a completely randomized block design with three replications. Data were submitted to factor analysis, reducing the variables to four factors: mass development, tiller mortality, developmental stage and leaf longevity. The data were submitted to cluster analysis by Tocher's optimization by adopting the mean Euclidean distance as a basic measure of dissimilarity. Grasses were grouped as follows: Summer - the group I (Xaraés, Massai, Mombaca and Marandu); group II (Molassa and Aruana); and group III (Jaraguagrass). Fall - group I (Mombaca, Massai, Xaraés, Marandu and Molassa); group II - (Jaraguagrass); and group III (Aruana). Possibly, the greater role of the tiller mortality factor in the formation of groups in the fall influenced the reorganization of the groups. The patterns of mass development of the different groups of grasses differ from each other as for the means of utilizing the resources available. There was a change in the scores of all factors with the change of the period from summer to Fall. The functional clustering of grasses demonstrates that gender and/or different species can be placed in the same group.
evaluation of grasses; morphogenesis; multivariate analysis; structural characteristics
