Influência de restos de cultura na antracnose do feijoeiro a partir de sementes com diferentes níveis de inóculo

Abstract

The anthracnose, whose etiologic agent is Colletotrichum lindemuthianum, is considered one of the most important seed-borne, seed transmitted. Thus, the aim was to study the influence of crop debris in bean anthracnose from seed with different levels of inoculum in epidemics whose etiological agent was transmitted exclusively by seeds, with different levels of seed infection in artificially infected areas with and without crop debris. The seed inoculation with C. lindemuthianum was done by the water restriction method. The experiments were conducted in a randomized block design with four replicates and six treatments in the city of Ijaci-MG and consisted of infection levels: 0, 0.25, 0.5, 1.0, 2.0 and 4.0 % of seeds infected with C. lindemuthianum. The assessment was made weekly and evaluated the incidence and severity of illness of ten randomly selected plants per plot. For the 2009 sowing December, the area with debris showed greater progress for both incidence and disease severity in relation to the area without crop debris. For the 2010 sowing April, progress in the incidence and severity was similar for both planting areas. According to the variance analysis performed for the sowing in December, it was observed for both incidence and disease severity, a significant interaction (P <0.05) between levels of infection in seeds and the different assessed areas. For the sowing in April, the interaction was significant (P <0.05) between levels of infection in seeds and the different areas assessed only for the incidence of the disease. The severity of this planting was significant for inoculum levels and different planting areas evaluated separately. Grain yields for both crops was higher for the area without crop residues, therefore, where the disease intensity was higher, the production was lower.