Pestalotiopsis funerea (Desm.) Steyaert occurs worldwide and is reported as an opportunistic invader of conifers. It can also be have as a primary pathogen. During the spring of 2001, leaf yellowing was observed on mature and young Cupressocyparis leylandii trees in some nurseries in northern Italy. Symptoms were first observed on twig tips and progressed toward the stem during the summer, resulting in twig dieback and death of branches up to 15 mm. Dark acervuli were present in the cankers. Isolations were made from cankers and necrotic twigs by removing the outer tissue and placing wood slivers from affected tissues on potato dextrose agar. P. funerea was isolated from 88 and 72% of cankers and necrotic twigs, respectively. Four isolates were selected for inoculation tests. Inoculations were made in September on the upper part of stems of 4-year-old pot-grown C. leylandii saplings. The outer layer of the bark (5 × 3 mm) was removed, and a 5-mm-diameter mycelial plug on malt extract agar (MEA) was placed on the wound and covered with Parafilm. Sterile MEA plugs served as controls. The experiment included 20 replications for each isolate and the control. After 4 weeks, 80% of inoculated plants showed bark necrosis or small cankers, or both, and 20% died. P. funerea was reisolated. No cankers developed in the controls. P. funerea was previously reported in Italy on Thuja orientalis L. (2) and from France on C. leylandii (1), but to our knowledge, this is the first report of the pathogen on C. leylandii in Italy.
References: (1) M. Morelet. Rev. Hortic. 227:35, 1982. (2) A. Panconesi and G. Vettori. Inf. Fitopatol. 5:37, 1994.
