Abstract

In recent years, severe natural olive anthracnose infections have been observed in orchards of Southern and Central Italy, favoured by mild and rainy seasonal trends, making disease control with the sole use of copper fungicides difficult. Besides, European restrictions in the use of copper compounds for eco-toxicological aspects have forced researchers towards the use of available plant protection products. Thus, 2 year investigations (2014-2015) was carried out in a Calabrian olive orchard (Southern Italy) to evaluate the efficacy of different commercial fungicides (copper oxychloride, tebuconazole/ trifloxystrobin mixture and tebuconazole/trifloxystrobin mixture plus copper  oxychloride) in controlling olive anthracnose on 2 CV. Ottobratica (highly susceptible) and Carolea (susceptible). In 2014, anthracnose incidence on Ottobratica ranged from 2% (April) to 21% (November), while in 2015 it was 15 and 29%, respectively. In both years, CV. Carolea showed a higher disease incidence ranging from 22% (April 2014 and 2015) to 56 and 46% in November, 2014 and 2015, respectively. In both years, 3 applications, in April, June and October, with the mixture of tebuconazole/trifloxystrobin and  copper oxychloride were the most effective, significantly reducing anthracnose incidence on Ottobratica (11 and 6%) and Carolea (13 and 11%), respectively in November 2014 and 2015. Moreover, the mixture showed a satisfactory activity on primary and secondary infections. The results also showed that respecting fungicide decay curves, the residue levels in extra-virgin olive oil for all tested pesticides were well below European MRLs.

Key words: Olea europaea, Colletotrichum spp., leprosy, epidemiology, fungicides, Integrated Pest Management (IPM).