Intensity of Anthracnose in resistant varieties (PIWI) in the high altitude regions of southern Brazil

Abstract

The objective of this study was to evaluate the different degrees of tolerance to Anthracnose infection in three PIWI varieties (Cabernet Cortis, Regent and Bronner) compared to the Cabenert Sauvignon variety. The experiment was conducted at EPAGRI Experimental Station, located in the city of São Joaquim, Santa Catarina State (28°17′39″ S; 49°55′56″ W, altitude 1,415 m a.s.l.), during 2016/2017 growing season. The evaluation of the disease was performed every 15 days, applying a scale of notes, from the onset of symptoms, and lasted for a period of two months, under the condition of infection Natural. The intensity of the disease was compared by epidemiological measures: time to reach maximum disease severity (TRMDS), maximum disease severity (Smax), and area under the severity disease progress curve (AUDSPC). Maturity indices of the varieties were obtained from juice physical-chemical analysis at the harvest. Although the PIWI varieties were resistant to mildew, they were susceptible to anthracnose. Bronner and Cabernet Cortis showed on average the same intensity of disease in the leaves and branches as the Cabernet Sauvignon variety, the Regent variety showed greater susceptibility to the pathogen, differing statistically from the other varieties evaluated.