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Mycosphaerella graminicola (anamorph: Zymoseptoria tritici) is the causal agent of leaf blotch, the most important foliar disease of wheat in Northern and Central Europe. In Italy only during the last few years, the incidence of the disease has been increased. The most common strategies for the control of the disease is the use of fungicides in particular QoIs, DMIs, and more recently were introduced the SDHIs. The resistance to QoIs and DMIs was already common in the main wheat cultivated areas in the world (Cools and Fraaije, 2008; Estep et al., 2015; Fraaije et al., 2005; Gisi et al., 2005; Leroux et al., 2005; Stammler and Semar, 2011; Stewart et al., 2014) while in Italy no results coming from wide and specific sensitivity monitoring are available. The aim of this study was to test the sensitivity of Z. tritici strains to QoI in order to obtain the first data about the Italian scenario. Leaves of bread and durum wheat were collected during 2015 from 10 fields with different use of fungicides (wild type, experimental centers and commercial ones) located in the North of Italy. The sensitivity of 60 isolates to azoxystrobin at different concentrations (0-0.001-0.01-0.1-1-2-10-20 mg/L of active ingredient) have been determined in vitro by microtiter assay (Stammler and Semar, 2011). The EC50 values of the wild types ranged from 0.02 to 0.12 mg/L of azoxystrobin, while the first analyzed isolates collected from experimental plots and commercial fields showed EC50s variable from 1.92 to 5.1 mg/L. Only one isolate pointed out an EC50 of 20.6 mg/L of active ingredient. On the base of these first results, we can suppose the presence of a slight decrease of sensitivity of Z. tritici isolates collected from Italian fields (according to Gisi et al., 2005). Molecular analysis on the presence of G143A substitution will be carried out.

Mycosphaerella graminicola (anamorph: Zymoseptoria tritici) is the causal agent of leaf blotch, the most important foliar disease of wheat in northern and Central Europe. In Italy only during the last few years, the incidence of the disease has been increased. During 2015 a Z. tritici population was collected by different cultivar of bread and durum wheat cultivated in experimental plots and commercial fields of Emilia-Romagna region (North Italy). The aim of the study was to test the pathogenicity of each Z. tritici strains on both (bread and durum) wheat species in greenhouse. In fact, some researchers observed that the majority of strains isolated from durum wheat are lowly virulent on bread wheat cultivars, whereas the majority of strains isolated from bread wheat are lowly virulent on durum wheat (Gohari et al., 2015 Mol. Plant Pathol.,16: 931–945). Another aim was to test the sensitivity of Z. tritici population to fungicides as strobilurins by in vitro assays. The preliminary data about pathogenicity confirm the cultivar specificity in the infection process. Further data are required in order to confirm the hypothesis in an Italian Z. tritici population too. The results about sensitivity test showed an EC50 value of the wild types ranged from 0.1 to 2.88 mg/l of azoxystrobin, while the isolates collected from experimental plots and commercial fields showed EC50 value ranged from 0.01 to 5.1 mg/l. These first results show a slight decrease of sensitivity of Z. tritici isolates collected from Emilia- Romagna region (according to Gisi et al., 2005 Modern Fungicides and Antifungal Compounds IV, pp 89-101).

Septoria tritici blotch (STB) is one of the most damaging disease of wheat caused by Zimoseptoria tritici (formerly known as Mycosphaerella graminicola / Septoria tritici) and worldwide spread. SBT is the most important foliar disease of wheat in America, Asia, Northern, Central Europe and it is a major disease, particularly on durum wheat, in North Africa. In Italy the average severity of STB infection, detected from 2000 up to 2015 on durum wheat varieties, has shown an exponential growth trend, that reached its peak between 2007-2010 with a further peak in 2013 and a slight decline in the last two marketing years. In the plain area environment of Bologna (Emilia Romagna region - North of Italy) the infection is due to Z. tritici with yield losses of 30% in years with high inoculum pressure. The aim of this study has been to evaluate, in the plain of Bologna, in two years field trial, the presence of Z. tritici on the flag leaf in San Carlo, a susceptible Italian durum wheat cultivar, after a single artificial inoculation at different vegetative stages (BBCH 31, 35, 39, 60) with two different inoculum concentration (105 and 106 conidia/ml). Visual assessments (Incidence, Disease severity -DS) and DNA quantification by Real time PCR, using the primer pair ST-rRNA F/R (Guo et al., 2006; Presymptomatic and quantitative detection of Mycosphaerella graminicola development in wheat using Real Time PCR. FEMS Microbiol Lett 262:223-229), were set up. The results demonstrate that the BBCH 39 is the most susceptible stage, independently by the concentration of inoculum and climatic conditions: the year 2012 was characterized by a low infection pressure of the pathogen, while year 2013 was characterized by a high infection pressure. In the 2013 a good correlation between DS and DNA quantity was observed. The results obtained point out that the most suitable period to obtain the best crop protection could be the flag leaf stage, even if Northern Italian farmers perform the fungicide treatment against STB earlier, at BBCH31 in association with the herbicide treatment, because cost-effective.

Fusarium species are responsible of severe ear rot on maize (Zea mays L.). Pink ear rot is caused mainly by F. verticillioides (Saccardo) Niremberg, F. proliferatum (Matsushima) Nirenberg and F. subglutinans (Wollenweber & Reinking), all mycotoxin producers. The most important mycotoxins are fumonisins, largely found in naturally contaminated foods and feeds. The presence of these fungi as endophytes was reported in leaves, stems, roots, grains, but not associated to particular symptoms. Only F. verticillioides is associated to a root and stalk rot in Italy. During routine testing of seed germination of maize samples, using standard methods, the presence of abnormal seedlings, characterized by mesocotyl rot, was observed with an incidence ranging from 4 to 42%. Mycological analysis, conducted on agar medium (PDA), revealed the presence of fast growing colonies with a white-dark violet aerial mycelium on 100% of the samples. Through morphological and molecular techniques, F. verticillioides and F. proliferatum were identified with a frequency of 87% and 13%, respectively. For both fungi Kock’s postulates were verified by artificial inoculation either dipping seeds or seedling roots in a conidial suspension (1 × 106 conidia/ml). Both fungi reproduced the same symptoms. To our knowledge this is the first report confirming seedling blight caused by F. proliferatum on maize seed for the Italian market. In a situation of changing climatic conditions, this may become a relevant pathogen, and neglecting seed transmission could be potentially dangerous, due to severe post-emergence damping off of seedlings.

Fusarium Head Blight (FHB) is a cereal disease widespread throughout the world and mainly studied in wheat. In barley (Hordeum vulgare L.) its fungal agents can affect yield crops and reduce the quality of grains for beer manufacture due to the production of several mycotoxins. Furthermore, during the malting process, some Fusarium species can produce special proteins called “hydrophobins” responsible of “beer gushing” that influences beer quality. Artificial inoculations on cv Quench with Fusarium graminearum, F. culmorum and F. poae have been performed in experimental field trials in the years 2013-2014, to evaluate the effects of FHB on barley malt. Disease incidence and severity were assessed. Fusarium Damaged Kernels (FDK), the presence of Deoxynivalenol (DON), T-2 and HT-2 mycotoxins were evaluated. In addition, the species of Fusarium isolated were morphologically and molecularly identified. The results showed that the average incidence of mixed inoculum (F. graminearum and F. culmorum) was 15% while F. poae alone 28%. These low values were confirmed by FDK. Fusarium spp. was reisolated on 2% of the tested kernels, and F. culmorum was the prevalent species. The levels of DON, T-2 and HT-2 mycotoxins were lower than the limits set by the European regulations and recommendations. We can conclude that the trends of the temperature and precipitation, in the investigated area and at the time of the study, were not favorable for the establishment of FHB disease. Then the grains of barley malt maintained their quality avoiding the gushing risk.

Italy is the first European producer of hazelnuts (Corylus avellana L.) and second in the world after Turkey. The orchards are mainly located in Piedmont, Lazio, Campania and Sicily. In 2013 a sample of hazelnut leaves from Piedmont, showing necrotic spots, has been analyzed. The aims of this work have been to identify the causal agent and verify Koch's postulates, since specific references in literature are not present. Colonies with a white aerial, dense mycelium with black acervuli close to center, similar to ink drops, grew really fast from hazelnut leaf samples plated on PDA. At light microscope the conidia appeared ellipsoid 4-septate, with three brown central cells, the basal and apical cells hyaline and with appendages. Morphologically the fungus was identified as Pestalotiopsis spp. Molecular identification has still not been successfully applied for species-level differentiation. Furthermore pathogenicity tests on leaves, both in vitro and in vivo, were set up at different temperatures. Positive response and a better infection resulted at 20°C. Pestalotiopsis was reisolated from the leaf tissues artificially infected. Pestalotiopsis spp. on hazelnut has been reported in different countries, in particular P. macrospora was found to be pathogenic on leaves and twigs in İran and P. guepinii in Turkey. Furthermore in 2015 Pestalotiopsis spp. was reported to cause disease on halzenut fruit clusters in Turkey, causing yield reduction. This work is the first report of Pestalotiopsis in hazelnut in Italy. Due to the economic importance of this crop in Italy, the incidence of this fungus should be monitored.