Reação de clones de batata à sarna comum (Streptomyces scabies)

Abstract

Seventeen potato clonal families from the Potato Breeding Program of Federal University of Lavras (UFLA) and the cultivars Agata, Asterix, Atlantic, Caesar, Cupido, IPR Cris, Markies and Snowden were assessed for the level of resistance to common scab under greenhouse conditions, and for tuber yield and qualitative characteristics of tubers under field conditions. Aiming to identify potato clones with high levels of resistance to common scab, tubers from 86 clones were sprayed with the inoculum of Streptomyces scabies suspension and planted in pots in a randomized block design with five replications. The bacterial suspension was prepared in the Plant Bacteriology Laboratory, Department of Plant Pathology/UFLA at a concentration of 10 7 CFU.mL -1 . The control consisted of pots with cultivars without inoculum. By 102 days after planting, the tubers were harvested and the severity of the disease was evaluated. The same treatments and two additional cultivars - BRS Ana e BRS Camila - were evaluated in the field, in a randomized block design with three replications for yield, tuber specific gravity and appearance of tubers. It was possible to identify clones with good resistance to common scab, besides having high yield and/or good qualitative characteristics of tubers. The clones TSB 03-06, IND 03-28, IRF 13-02, IND 06-08 and TSB 08-04 showed the highest common scab resistance levels. Among these, TSB 03-06, IRF 13-02 and TSB 08-04 had good yield and/or good quality characteristics of tubers