Regional evaluation of Stylosanthes germplasm in Brazil.

Accessions and cultivars of Stylosanthes capitata, S. macrocephala, S. guianensis, S. scabra and S. seabrana were evaluated for agronomic performance and anthracnose resistance at five field sites in Brazil spanning the states of Chapadão do Sul-MS, Goiânia-GO, Planaltina-DF, Sete Lagoas-MG and Teresina-PI. The field trials were laid out as a complete randomised block design replicated four times and planted at the beginning of the rainy season. Each replicate 5x2 m plot consisted of four rows of each accession/cultivar. Data on dry matter, seed yield and anthracnose severity were collected during two years of this study and analysed separately for each site. Results showed considerable genetic variability among the germplasm of Stylosanthes studied for each character. The most promising accessions yielded 11-16 t dry matter/ha annually and seed yields reached up to 600 kg/ha. Anthracnose was a serious problem on susceptible accessions at some sites with high rainfall. The study forms a basis for the targeting of specific accessions to suit regional climatic conditions.Autoria na publicação: Maria do Socorro Bona Nascimento