The objective of this work was to characterize Colletotrichum sublineolum Henn. population by evaluating virulence of 289 single spore isolates of the pathogen in sorghum 10 elite lines of the breeding program of Embrapa Maize and Sorghum Research Center, utilized as differentials. Isolates were obtained of sorghum leaves from Palmeira de Goiás and Goiânia, GO, Sete Lagoas, Ipiaçu and Uberlândia, MG, and Jardinópolis, SP and designated according to a binary system of classification. Populations were also characterized for phenotypic diversity according to the Shannon, Gleason and Simpson indexes, a complexity index, and according to their frequency and distribution. Race 31.04 was present in all six locations and was the predominant phenotype in Uberlândia, Ipiaçú, and Palmeira de Goiás. The complex race 31.31, was the most frequent in Sete Lagoas and Goiânia and was not observed only in Palmeira de Goiás. The most frequent races were also the ones with a uniform distribution throughout the six locations. The highest phenotypic diversity, according to the Shannon, Simpson and Gleason indexes, was observed in Jardinópolis. The highest complexity index was found in Sete Lagoas and Goiânia, followed by the indexes of Jardinópolis, Ipiaçu, Uberlândia and Palmeira de Goiás, respectively. A significant correlation between Shannon and Gleason indexes was observed. On the other hand, diversity and complexity indexes were not significantly correlated.
Sorghum bicolor; Shannon; Simpson; Gleason and Complexity indexes
