Isolation and biology of aStreptomyces sp. causing potato scab in soils below pH 5.0

Summary

Isolates of an acid tolerantStreptomyces sp. were obtained from lesions of potatoes grown in soil with a pH below 5.0. Isolates ofS. scabies were obtained only from lesions of tubers grown in soil with the pH above 5.2. Isolates of the acid tolerantStreptomyces sp. caused tuber lesions on potatoes grown in soil at pH 4.5 or 5.9. Isolates ofS. scabies were pathogenic in soil at pH 5.9, but not 4.5. Physiological tests and morphological observations suggest that the acid tolerant organism is notS. scabies. It is believed thatStreptomyces sp. is a causal agent of potato scab in acid soils.

Resumen

Cultivos deStreptomyces sp., patógeno ácido toleronte, fueron aislados de lesiones de papas infectas crecidas en suelos con pH menor que 5.0. Cultivos deS. scabies fueron obtenidos solamente de tubérculos crecidos en suelos con pH mayor que 5.2. El patógeno ácido toleronte,Streptomyces sp., ocasiono lesiones en papas crecidas en suelos con pH 4.5 y 5.9.S. scabies ocasionó lesiones en papas desarolladas en suelos con pH 5.9, pero no en pH 4.5. Investigaciones fisiológicos y morfológicos sugieren que el microorganismo ácido toleronte no esS. scabies. Se dedujo queStreptomyces sp. es un agente responsable de la sarna de la papa en suelos ácidos.