Reaction of mandarin cultivars to anthracnose under different irrigation systems

The mandarin is one of the most commercially important Citrus species. However, a large number of pathogens have affected this crop, specially the fungus Colletotrichum gloeosporioides, which causes anthracnose. The latter may lead to significant economic damage, causing both yield and fruit quality losses. The aim of this study was to evaluate the resistance of mandarin cultivars to anthracnose under different irrigation systems. The incidence of anthracnose was studied by using three cultivars under three cultivation systems. The cultivars were 'Murcott', 'Ponkan' and 'Cravo', grafted onto Rangpur lime rootstock, while the irrigation systems were micro-sprinkler and drip irrigation. A rainfed control was included. Results showed that plants grown under irrigation are more resistant to anthracnose than those under rainfed conditions, and the cultivar 'Ponkan' had greater genetic resistance to anthracnose. There was also a positive correlation between the incidence based on the percentage of affected plants and the incidence based on the number of affected branches per plant.