Quantification of citrus canker in mandarin trees grafted on different rootstocks

Abstract

Citrus canker caused by the bacteria Xanthomonas citri subsp. citri is an important disease in Santa Catarina State (Brazil) and can reduce citrus plant production. In this work, the objective was to evaluate the incidence of citrus canker in different cultivars of tangerine and rootstocks. Canker occurrence was evaluated along ten years in the scion cultivars ‘Satsuma EEI’, ‘Tankan EEI’, ‘Michal’ and ‘Niva’ budded on ‘Troyer’, ‘C-41’, ‘Cleopatra’ and ‘Sunki’. Evaluated characteristics were citrus canker incidence on leaves and stems, proportion of fallen leaves, the sum of leaves with canker and fallen leaves and the proportion of leaves with citrus leaf miner (Phyllocnistis citrella Stainton). Areas under the progress curve (AUPC) of each variable were calculated and compared. Citrus canker incidence on leaves and stems occurred in all cultivars, but was higher in tangerine ‘Niva’. The rootstocks ‘C-41’ and ‘Sunki’ provided lower incidence of citrus canker on leaves of tangerine cultivars.