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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.

Fusarium Head Blight caused by phytopathogenic Fusarium spp. with Fusarium graminearum as main causal agent is a major disease of durum wheat (Triticum durum Desf.). Mycotoxins in wheat are dominated by trichothecenes B. Fumonisins have only occasionally been reported from wheat; their occurrence was attributed to Fusarium proliferatum and Fusarium verticillioides. We investigated kernels of durum wheat grown in Italy in 2008 - 2010 for colonization with Fusarium spp. and for the content of Fusarium mycotoxins. Fungal biomass was determined using species-specific qPCR and mycotoxins were quantified by HPLC-MS/MS. Fusarium graminearum and Fusarium culmorum were dominating Fusarium species, followed by Fusarium poae, Fusarium tricinctum, and Fusarium proliferatum. No Fusarium verticillioides DNA was found. Toxicologically relevant levels of deoxynivalenol and nivalenol but no trichothecenes A were detected. Enniatins, fumonisin B1 and beauvericin were present in grain in all three years. Based on these results and on the evaluation of previous published reports, we hypothesize that low levels of fumonisins commonly occur in wheat grains produced in warm climate; they may remain undetected as long as mycotoxin monitoring programs for wheat do not include fumonisins. The only relevant source of fumonisins in wheat grain appears to be Fusarium proliferatum., Journal of Applied Botany and Food Quality, Vol 88 (2015): Journal of Applied Botany and Food Quality

Background: Fusarium head blight (FHB) is a severe disease caused by different Fusarium species, which affects a wide range of cereal crops, including wheat. It determines from 10 to 30 % of yield loss in Europe. Chemical fungicides are mainly used to reduce the incidence of FHB, but low environmental impact solutions are looked forward. Applications of soil/rhizobacteria as biocontrol agents against FHB in wheat are described in literature, whereas the potential use of lactobacilli in agriculture has scarcely been explored. Results: The aim of this work was to study the inhibitory effect of two bacterial strains, Lactobacillus plantarum SLG17 and Bacillus amyloliquefaciens FLN13, against Fusarium spp. in vitro and to assess their efficacy in field, coupled to the study of the microbial community profile of wheat seeds. Antimicrobial assays were performed on agar plates and showed that the two antagonistic strains possessed antimicrobial activity against Fusarium spp. In the field study, a mixture of the two strains was applied to durum wheat i) weekly from heading until anthesis and ii) at flowering, compared to untreated and fungicide treated plots. The FHB index, combining both disease incidence and disease severity, was used to evaluate the extent of the disease on wheat. A mixture of the two microorganisms, when applied in field from heading until anthesis, was capable of reducing the FHB index. Microbial community profile of seeds was studied via PCR-DGGE, showing the presence of L. plantarum SLG17 in wheat seeds and thus underlining an endophytic behavior of the strain. Conclusions: L. plantarum SLG17 and B. amyloliquefaciens FLN13, applied as biocontrol agents starting from the heading period until anthesis of wheat plants, are promising agents for the reduction of FHB index.

Fusarium proliferatum is an emerging, spreading worldwide pathogen of garlic, causing bulb rot. During the whole crop cycle, fungal presence is not associated to characteristic symptoms. During storage, infected bulbs, conversely, undergo to a slow deterioration process: at first brown depressed water soaked spots and, in extremely severe infections, the entire bulbs rot, reducing the garlic shelf-life. The disease leads to appreciable loss of product. This fungus is well known to produce fumonisins. White garlics, cultivated in different northern Italian regions are subjected to mycological and HPLC analysis, to detect the pathogen and quantify the mycotoxins. Basal plate of garlics were dissected and cultured in PDA Petri dishes amended with streptomycin and neomicyn sulphate. Strains morphologically belonging to F. proliferatum species were tested by PCR with specific primers and with primers for Fum1 gene involved in fumonisin production. For mycotoxin analysis, cloves were dried for one week at 40°C, grinded in fine powder and analyzed by IAC/HPLC. F. proliferatum is present in all the tested bulbs and all the strains collected show the presence of FUM1 gene. The Fumonisin levels in cloves ranged from 0,05 ppm to 0.68 ppm for B1 and up to 0.1 for B2. These quite low levels are reached within a short period of conservation in comparison to the time from storage to consumption. Mycotoxin levels should be checked in different food chain steps and on garlic derived products, therefore it is necessary to consider the influence of the conservation time at home, by consumers to better evaluate the possible risk in human health.

A rapid decay of Poplars AF2 clone, Populus x canadiensis, selected for biomass production addressed to produce energy and with an elevated tolerance to several harshnesses, has been observed in year 2013 in three fields (41.5ha) in Bologna Province. These fields were set in March 2010, pruning in two of the three fields was not done at the due time, since plants showed a scarce growth, with an incidence over 80%. Observations and samplings were done on plants of plots (10x10m) of each field. Trunk cross sections of all tested plants showed a central area, at 8cm from the soil, completely necrotic surrounded by a typical reddish ring extended up to 60%. Fungal colonies with fluffy grey mycelium were isolated from woody fragments, plated on agar medium. Their identification through sequencing of partial rDNA ITS region was performed comparing sequences in the NCBI database by BLASTn search algorithm. The nucleotide search comparison showed 98% identity with Cryptosphaeria lignyota (Fr.) Auersw. This fungus has been reported in literature as responsible of wood decay of some plant species, i.e. genus Populus and especially those with rapid growth. It can kill young trees within a year from infection and contributes to natural thinning of trunk formations. It seems that the host death might be due to massive invasion of the sapwood, that prevents it from transporting water and nutrients, and not to annular extension of the canker. The fungus is responsible of a great economic loss being all the infected plants highly compromised.

Lactic Acid Bacteria [LAB] are worldwide known as probiotic microorganisms. One of the most important probiotic feature is their strong activity against a wide range of harmful bacteria/fungi (Gaggìa et al., 2011). Production of organic acids and production of antagonistic compounds are the main mechanisms described nowadays. This work focuses on the in vitro selection of LAB strains isolated from environmental sources against Fusarium genus. Fusarium is a well distributed genus of filamentous fungi affecting plant, animal and human health. In the agricultural field, Fusarium is one of the most important plant pathogenic genera, with a record of devastating infections in various economically important plants. In this study, in vitro antagonistic effects of 18 isolates of Lactobacillus spp. were evaluated against F. oxysporum f. sp. lactucae, agent of tracheofusariosis in Lactuca sativa, F. culmorum and F. graminearum, agents of severe diseases in cereals. Fungal inhibition was performed using spot agar test in a triplicate assay (Magnusson et al., 2003). Overnight cultures of LAB were inoculated as spot on MRS agar plates and allowed to grow at 30°C for 24 h. The plates were then overlaid with 10 ml of PDA containing 104 mould spores/ml. After 48-72 h of aerobic incubation at 25°C, the zone of inhibition was measured. All LAB strains (except one) showed antifungal activity against all Fusarium species (inhibition halo between 23.7- 65.3 mm). The highest halos were obtained against F. graminearum on which 50% of the LAB strains showed a total growth inhibition of the colony. These results are probably related to the high amount of organic acids produced by LAB strains but it can also be hypothesized the presence of antifungal compounds. In vivo application of the most successful LAB strains is foreseen towards wheat and lettuce to confirm in vitro results.

Use of biological control agents, such as plant growth promoting rhizobacteria (PGPR), and Lactic Acid Bacteria (LAB) can be a suitable approach in control of disease in vegetable crops to reduce and limit the widespread use of chemicals. PGPR, such as Pseudomonas and Bacillus strains, are the major root colonizers that can elicit plant defense and compete with pathogens. Lactic Acid Bacteria [LAB] are worldwide known as probiotic microorganisms and one of the most important probiotic feature is their activity against a wide range of harmful bacteria/fungi. Their use as “effective microorganisms” is increasing as active components of soil amendments for sustainable agriculture. This work focuses on the in vitro screening of 32 PGPR and LAB strains isolated from environmental sources against Fusarium spp, Sclerotinia spp. and Rhizoctonia spp which are widely distributed fungi affecting plant, animal and human health. In the agricultural field, they are considered important plant pathogenic fungi, with a record of devastating infections in various economically important crop plants. Fungal inhibition was performed using spot agar test in a triplicate assay with different conditions for LAB and PGPR. All LAB strains (except one) showed an antifungal activity against all Fusarium species tested (inhibition halo between 23.7- 65.3mm); the highest halos were obtained against F. graminearum on which 50% of the strains showed a total growth inhibition of the colony. Among PGPR, preliminary results showed a strong inhibition by some B. subtilis strains against all fungi tested. These results are promising for the formulation of a commercial product that could be used for a wide spectrum of plant crops. In vivo application with the most successful strains is foreseen towards wheat and lettuce to confirm in vitro results.

Fusarium Head Blight (FHB), or scab, is a cereal disease widespread throughout the world and it has been studied mainly in wheat. FHB can cause significant yield losses and quality reductions, especially if during fungal infection dangerous mycotoxins for the human and animal health are produced. In the last years, in Italy, barley production for malting industry has undergone a positive trend that it shifts major attention to the barley diseases. FHB symptoms in barley differ in part from those in wheat. In wheat, premature death or bleaching of spikelets is a typical symptom, particularly clear on emerged immature heads. Pink to salmon-orange spore masses of the fungus are often formed on the infected spikelets and glumes during prolonged wet weather. In barley, symptoms of infection are shown by a bleached appearance too, but also a browning or water-soaked appearance or even a little brown spots on the glume are noticed. Salmon-orange spore masses of the fungus can be rarely observed. In wheat the severity index of the FHB is calculated with the rating scale proposed by Parry et al. (1984) that evaluates the percentage area infected on individual ears with values among 0% and 90%. The aim of this work is to set up a FHB scale for barley, similar to that used by Parry, taking as reference tow-row barley cultivar artificially inoculated in an experimental field. This rating scale can be useful also to the breeders to evaluate the different susceptibility of barley cultivars.

The mycotoxin contamination of flours is an important concern of the organic sector, in which no fungicide can be applied to the crop. The most common toxin occurring in wheat flours is deoxynivalenol (DON) that belongs to the trichothecene class and is produced by several fungi of the Fusarium genus (mainly F. culmorum and F. graminearum). Two different field experimental trials were set up for two subsequent growing seasons (2009/2010; 2010/2011): 1) comparison between 1 modern (Palesio) and 5 old (Inallettabile, Andriolo, Gentil Rosso, Verna, Frassineto) common wheat varieties under organic farming; 2) comparison between one old durum-type (Kamut®Khorasan) and one modern durum wheat variety (Claudio) under organic farming. Different DON accumulation in the grains was observed comparing the two cropping years as a result of changing weather conditions: wheat varieties grown during the first cropping season presented higher mycotoxin levels (0.19 and 1.19 mg/kg for common and durum wheat, respectively) as compared to those observed in the second year (0.02 and 0.33 mg/kg for common and durum wheat, respectively). The higher DON levels of Kamut and Claudio flours confirmed the higher susceptibility of durum-type wheat to Fusarium head blight, but no differences were observed among genotypes for each wheat species. Interestingly, despite of the interdiction in using fungicides, in common wheat cultivars grown according to organic farming the mycotoxin content was lower than the legislative limits set for all the food categories, as indicated in the current EU regulation (EC N. 1126/2007).

Fusarium graminearum is a common agent causing Fusarium head blight (FHB) on wheat throughout the world. Aggressiveness is crucial for understanding the interaction between host-pathogen in the FHB-wheat system. In this paper, we modified and validated the Petri-dish test originally described by Mesterhazy (Phytopathologische Zeitschrift 93:12–25, 1978) to quantify the aggressiveness of 25 F. graminearum strains using four durum wheat cultivars with different resistance levels for FHB. The results were highly significant and correlated with those obtained using adult plants in the growth chamber and in the field (r = 0.94, P

Durum wheat production in Italy is economically of great importance. Fusarium graminearum is the main fusarium head blight (FHB) causal agent in wheat, reducing both yield and grain quality. F. graminearum produces several mycotoxins and, among trichothecenes, deoxynivalenol (DON) and nivalenol (NIV) are the most studied for their toxicity towards humans and animals. DON-producing isolates can be further distinguished on the basis of the predominant acetyl-DON derivative in 3-acetyldeoxynivalenol (3-ADON) or 15-acetyldeoxynivalenol (15-ADON). In order to evaluate possible mycotoxin contamination risks in food, it is very important to know which chemotype is the prevalent in a F. graminearum population. F. graminearum sensu stricto strains were collected from symptomatic durum wheat heads and grains of several naturally infected fields located mostly in Emilia - Romagna, The Marche, Lazio, Tuscany and Umbria. A multiplex PCR in the region of genes Tri12, located in the terminal gene cluster of trichothecenes, was used to characterize 187 single-spore isolates of F. graminearum as NIV, 3-ADON and 15-ADON chemotypes. All the three chemotypes were present in the F. graminearum population studied. The most frequent chemotype was 15-ADON (83.4%), followed by 3-ADON (10.7%) and NIV (5.9%). NIV-producing isolates were found only in Emilia-Romagna (3.5%), Umbria (33.3%) and The Marche (5.7%).

Since 2001 an unusual disease, named elephantiasis, was observed in the kiwifruit cultivar ‘Hayward’ in orchards of Northern Italy. The symptom typical of elephantiasis in kiwifruit is trunk hypertrophy, at which a marked brown discoloration of the annual rings is associated. Fungi isolated from necrotic sections of plants are belonging to different fungal genera such as Fusarium spp. - mainly F. solani, Cylindrocarpon spp. and Phialophora-like, that include Phaeoacremonium, Cadophora, Lecythophora. The kiwifruit plant tissue colonization capacity of P. aleophilum, Cadophora melinii and F. solani was verified, while pathogenicity trials using these fungi are in progress in an experimental field. To explain the trunk hypertrophy, trunks of diseased and asymptomatic plants coming from the same orchard were analyzed for the presence of hormones by HPLC-ESi-MS/MS. The hormones analyzed were abscisic acid (ABA), iasmonic acid (JA), salicylic acids (SA), indolacetic acid (IAA) and Gibberellins (GA1, GA3, GA4, GA34). The presence of these hormones showed a similar trend in the majority of the samples either from diseased and asymptomatic plants, except GA34 that it was present exclusively in diseased plants. Gibberellins (GAs) are a large family of hormones that can regulate germination, elongation growth and sex determination. GAs products by fungi are known to induce abnormal tissue growth. These results induce us to further investigate the possible direct production of Gibberellins by the fungi associated to this unusual disease and their involvement in the trunk hypertrophy.

Recenti infezioni a carico di rucola coltivata e selvatica in Italia sono state causate da Fusarium oxysporum f. sp. raphani. Considerando che i miceti riferibili alla specie F. oxysporum sono agenti di deperimenti o marciumi radicali su centinaia di ospiti vegetali, distinti sulla base di risposte ospite specifiche in formae speciales e che la specie è ubiquitaria e cosmopolita, risulta difficile effettuare una identificazione tempestiva e certa con il solo approccio morfologico. L’esatta identificazione degli agenti causali è punto cruciale nella valutazione della sanità delle sementi e nella gestione di questa problematica. Nel presente lavoro sono stati analizzati 39 lotti di semente, di cui 31 di rucola selvatica e 8 di rucola coltivata, su substrato semiselettivo (Komada’s medium) per la ricerca di Fusarium spp. Da questi lotti sono stati reperiti 24 isolati, che, unitamente a 2 ceppi di riferimento, sono stati saggiati biologicamente tramite prove di patogenicità differenziali in ambiente controllato e caratterizzati molecolarmente sulla base dello studio dei geni ITS e EF-1. Nessun isolato da seme, analizzato in questa indagine, risulta appartenere a F. oxysporum f. sp. raphani e la maggioranza dei ceppi fungini isolati appartiene a Gibberella fujikuroi Complex.

The economical importance of “ready to use” fruit and vegetable products (4th range), greatly increased in the last ten years; to date Lactuca sativa, Cichorium spp., Eruca sativa, Diplotaxis spp and Valerianella locusta cover a great part of the vegetable market. The final products quality can be achieved using healthy seeds and appropriate agronomic techniques. One of the most important pathogens of these species is Fusarium oxysporum: infected plants are usually stunted, leaves turn pale green to golden yellow and later wilt, wither, die and drop off progressively upward from the stem base. Browning occur in vascular tissue (xylem) of roots and lower stem, while roots may decay and seedlings sometimes wilt and die. Surviving seeds can act as source of primary inoculum. In the present work more than 100 seed lots of Diplotaxis spp., Eruca sativa, Lactuca spp. and Valerianella locusta have been analyzed, in order to assess the incidence of F. oxysporum on commercial seeds. Our data highlight the very low frequency of F. oxysporum infection and the presence of other Fusarium species belonging to Gibberella fujikuroi complex.

Fusarium head blight (FHB) of wheat is a very insidious disease caused by several fungal species prevalently belonging to the Fusarium genus. In Italy it has been permanently present since 1995. The most frequent species of Fusarium in wheat ears are F. graminearum and F. culmorum, but the composition of the population of Fusarium associated to this disease in the Emilia Romagna region, Northern Italy, has changed during the years. Our study has revealed the increased frequency of other Fusaria such as F. poae. The Fusarium species involved are responsible for yield losses and decreasing in grain quality characteristics, including the accumulation of mycotoxins, capable of harming the health of humans and animals. The F. graminearum strains were examined using specific primers for chemotypes based on the production of the trichothecenes, deoxynivalenol (DON) (15ADON and 3ADON) and nivalenol (NIV). The F. poae strains are also able to produce an extensive range of mycotoxins. In this work we found F. poae strains able to produce T-2 toxin, which is the most dangerous among all the trichothecenes of the classes A and B, and its derivative HT-2. The aim of the present work was to characterize the Fusarium strains for their ability to produce different mycotoxins and to test for their interaction by experimental trials, in order to control Fusarium head blight and limit the contamination of grains with mycotoxins.

Fusarium head blight (FHB) is a very important cereal fungal disease. In Italy, it has been permanently present in wheat since 1995. The most frequent species of Fusarium causing the disease are F. graminearum, F. culmorum and recently F. poae. These species are responsible for yield losses and decreasing grain quality characteristics, including the accumulation of mycotoxins responsible of serious health effects to humans and animals. The most dominant F. graminearum mycotoxins are the trichothecenes, with deoxynivalenol and nivalenol being the most prevalent derivatives. F. poae is able to produce an extensive range of mycotoxins and, in some cases T-2 toxin and its derivative HT-2. T-2 toxin is the most dangerous among all trichothecenes of classes A and B, with an LD50 value 20-times lower than deoxynivalenol. F. graminearum and F. poae strains, producing different mycotoxins, were tested for their interaction in vitro and in vivo trials. The strains were inoculated singularly or mixed in a durum wheat cultivar sensible to FHB. The incidence and the severity of the disease were also evaluated. In the flour obtained from the grains, real-time PCR and HPLC-MS were used to estimate the biomass of F. graminearum/F. poae and determine the amounts of mycotoxins, respectively. The aim of this work was to investigate the direct interaction between F. graminearum and F. poae, which might substantially contribute to the population dynamic of these species in the field. The interest of the scientific community in F. poae has been steadily growing due to its potential to produce dangerous mycotoxins. In order to control Fusarium head blight and limit the contamination of grain with mycotoxins, we need to better understand the role of F. poae in the disease and its ecology including interaction with other pathogens colonizing wheat ears.

Fusarium head blight (FHB) is the main worldwide wheat disease. In Emilia-Romagna region (Northern Italy), the most frequent species responsible of FHB on durum wheat were Fusarium graminearum and F. culmorum since 1995. FHB can cause losses in production (0.6-2.7 t/Ha) and seed quality, due to kernel infection and micotoxin accumulation. From 2000 to 2006, some DMI commercial fungicides were evaluated for their efficacy in controlling FHB incidence and severity, percentage of infected kernels and deoxynivalenol (DON) content in kernels. DMI were applied at anthesis stage (GS 60-61), in several cultivars of durum wheat, inoculated artificially with a mixture of F. graminearum and F. culmorum toxigenic isolates. Trials, on fourteen cultivars with bromuconazole, prochloraz and tebuconazole were performed from 2000 to 2002 and on four cultivars with epoxiconazole + prochloraz, cyproconazole + prochloraz, metconazole (not yet registered in Italy) from 2005 to 2006. These fungicides significantly reduced incidence and severity of FHB compared with the untreated control. The results showed an average efficacy in reducing the tested parameters of 53% and 68% respectively in the first experiment, 64% and 59% in the second. From 2000 to 2002 on six durum wheat cultivars, bromuconazole, prochloraz and tebuconazole significantly reduced the percentage of F. graminearum and F. culmorum infected kernels by averagely 63% and DON content of 66%, when compared with the untreated control. The knowledge of DMI efficacy in reducing FHB incidence and severity, infected kernels and DON content is very important for setting up disease control strategies.

Fusarium oxysporum f. sp. raphani è stato definito come agente causale del deperimento della rucola coltivata (Eruca sativa) e della rucola selvatica (Diplotaxis spp.) in Italia (Garibaldi et al., 2003). La principale fonte di diffusione, a lunga e a breve distanza, di questa tracheomicosi sembra essere il seme (Garibaldi et al., 2005). L’esatta identificazione degli agenti causali è punto cruciale nella valutazione della sanità delle sementi e nella gestione di questa problematica. Considerando che i miceti riferibili alla specie F. oxysporum sono agenti di deperimenti o marciumi radicali su centinaia di ospiti vegetali, distinti sulla base di risposte ospite specifiche in “formae speciales”, che la specie è ubiquitaria e cosmopolita, risulta difficile effettuare una identificazione tempestiva e certa con il solo approccio morfologico. Nel presente lavoro sono stati analizzati 49 lotti di semente, di cui 37 di rucola selvatica e 12 di rucola coltivata, su substrato semiselettivo (Komada’s medium) per la ricerca di F. oxysporum. Per l’individuazione di F. oxysporum f. sp. raphani, i 21 isolati collezionati, unitamente a 2 ceppi di riferimento, sono stati saggiati biologicamente tramite prove di patogenicità differenziali in ambiente controllato e caratterizzati molecolarmente sulla base dello studio dei geni ITS e TEF. Nessun isolato da seme analizzato in questa indagine risulta appartenere a F. oxysporum f.sp. raphani.

Fusarium oxysporum (Schlecht.) Snyd. & Hans., the most common species of the genus, is widely distributed in soil and on organic substrates. The species includes non-pathogenic, plant and human pathogenic strains. F. oxysporum f. sp. albedinis is the agent of bayoudh disease, causing the death of millions of mature and young date palm trees in North Africa. The aim of this work was to examine any correlation between the total microbial com- munity and the incidence of the disease in an Algerian oasis. A total of 38 soil samples were collected in 12 areas randomly cho- sen within the oasis of Azoua and screened for the presence of fungi, bacteria and actinomycetes. Microbes were isolated on se- mi-selective substrates (PDS, TSA and Chitin-Agar media). Mi- crobial entities were identified according to their morphological traits. For each soil sample, a statistical index of richness, domi- nance and evenness was determined. The microbial load ranged from 1.24 × 10 3 to 9.07 × 10 4 CFU/g for fungi, 4.00 × 10 5 to 3.22 × 10 7 CFU/g for bacteria and 8.60 × 10 4 to 9.92 × 10 6 CFU/g for actino- mycetes. The correlation between the incidence of bayoudh dis- ease, evaluated on a visual scale, in each area and the microbial community is reported

La recente nascita e sviluppo del mercato nutraceutico sta portando ad una sempre maggiore richiesta di colture ad elevato contenuto in composti noti per possedere effetti benefici per la salute dell’uomo. Tra questi i fitoestrogeni (FIT) e la melatonina (MEL), prodotti dalla pianta in condizioni fisiologiche e ancor più in risposta a stress biotici e abiotici, sono di grande interesse principalmente grazie alle loro proprietà antiossidanti, in un’ottica di rafforzamento delle difese naturali dell’organismo e per la prevenzione di patologie e disordini che colpiscono la donna e l’uomo occidentali (osteoporosi, sindromi pre-mestruali, neoplasie ormone-dipendenti). La presente relazione descrive la sperimentazione condotta dal nostro gruppo di ricerca su piante di leguminose. In particolare, i principali obiettivi sono stati la valutazione delle potenzialità di leguminose tipiche degli ambienti mediterranei, quali fagiolo comune ed erba medica, come fonti di FIT e MEL a livello del germoglio e della pianta adulta; la valutazione degli effetti di stress abiotici (fisici e chimici) e biotici (insetti e miceti) sulla sintesi e l’accumulo di FIT e MEL nel germoglio e nella pianta adulta; l’identificazione di nuove destinazioni d’uso per erba medica e fagiolo comune come piante funzionali per il consumo umano diretto (germogli per l’alimentazione) e indiretto (integratori e/o preparati nutraceutici); la definizione di nuovi protocolli produttivi in grado di assicurare un elevato e costante contenuto di FIT e MEL; infine, la valutazione della ricaduta clinica della ricerca in chiave di ottimizzazione dell’interazione in vivo di FIT e MEL.

Sweet cherry (Prunus avium L.) cultivation has increased in Italy and ≈30,000 ha are now in production. In the spring of 2006, a disease survey was conducted in orchards of central Italy. Decline symptoms of Prunus avium ‘Durone’ grafted on wild rootstocks of Prunus avium consisted of reduced tree vigor, yellowing of leaves, and development of root and collar rot. A reddish brown discoloration of the inner bark and wood was observed on symptomatic trees. Symptoms were recorded in three cherry orchards seasonally submitted to soil saturation conditions. In one orchard, symptoms were observed on approximately 30% of 170 surveyed trees. A Phytophthora species was consistently isolated on PARPH-V8 medium (2) from collar lesions of five cherry trees over nine trees randomly chosen among symptomatic trees in the three orchards. Colonies (20) were isolated and all appeared fluffy on potato dextrose agar and did not grow at 35°C. The morphological characteristics fit the descriptions of Phytophthora cryptogea Pethybr. & Lafferty (1). Sequence analysis of the internal transcribed spacers region of isolates shared 100% homology with P. cryptogea (GenBank Accession Nos. EF418948.1, EF418943.1, and EF153671.1). Pathogenicity of two P. cryptogea isolates (AN1 and AN2, Accession Nos. EF661576 and EF661577, respectively) was tested by soil infestation in a growth chamber at 22°C using 15 1-year-old rooted seedlings of wild rootstock of Prunus avium for each isolate. Noninoculated seedlings (15) were used as negative controls. The inoculum was produced by growing isolates on autoclaved millet grains moistened with V8 juice for 4 weeks. Each plant was inoculated with 30 cm3 of inoculum per liter of soil. Each seedling was randomly assigned to isolates AN1, AN2, or the noninoculated control and arranged in a complete random design. All plants were flooded for 24 h every 2 weeks for 8 weeks. At the end of the experiment, all inoculated seedlings showed crown wilting and root rot. Control plants showed no symptoms. Percentage of necrotic lateral roots expressed as dry weight (±SE) was 19.9 ± 0.6, 17.5 ± 0.2, and 4.4 ± 0.5, respectively, for seedlings inoculated with isolates AN1, AN2, and controls (analysis of variance F = 7.48, P < 0.01). Values of inoculated seedlings were significantly different from the control plants with the Tukey Post-Hoc test. No difference in virulence was observed between the two isolates. P. cryptogea was always reisolated from the roots of inoculated plants. Although pathogenicity of P. cryptogea on sweet cherry has been reported in the United States and other European countries (3,4), to our knowledge, this is the first record of P. cryptogea on sweet cherry orchards in Italy. The presence of P. cryptogea in cherry orchards is of significant concern because of its aggressiveness to this host and woody hosts such as apple, apricot, peach, walnut, and kiwi. References: (1) D. C Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul, MN, 1996. (2) A. J. Ferguson and S. N. Jeffers. Plant Dis. 83:1129, 1999. (3) T. Tomidis and T. Sotiropoulos. N. Z. J. Crop Hortic. Sci. 31:355, 2003. (4) W. F. Wilcox and S. M. Mircetich. Phytopathology 75:1451, 1985.

La verticillosi dell'olivo ha avuto in questi anni un'incidenza via via crescente negli areali vocati a questa coltivazione. Nel biennio 2003-2004, si è ritenuto importante, quindi, effettuare un monitoraggio preliminare per valutare la presenza di Verticillium dahliae anche in aree olivicole marginali. In generale, negli isolamenti effettuati è stata evidenziata una micoflora di tipo saprofitario e solo nel materiale vegetale proveniente dalle Marche sono state identificate colonie fungine riferibili a V. dahliae Kleb.

La verticilliosi dell'olivo ha avuto in questi anni un'incidenza via via crescente negli areali vocati a questa coltivazione. Nel biennio 2003-04 si è ritenuto importante effettuare un monitoraggio per valutare la presenza di Verticillium dahliae in aree olivicole marginali. Il reperimento di V. dahliae è risultato negativo da piante deperienti del Trentino e della Romagna, mentre si fa segnalazione del primo ritrovamento di V. dahliae nelle Marche, nella zona di Offida.

L’Actinidia è soggetta a varie malattie a carico del legno e fra queste l’elefantiasi, il cui sintomo caratterizzante è un’ipertrofia del tronco. I frutti prodotti da queste piante hanno forma rotondeggiante e taglia ridotta, parametri che possono limitarne la commercializzazione. Fino ad ora gli studi su questa malattia sono stati rivolti alla individuazione degli agenti causali, mentre le caratteristiche dei frutti sono state scarsamente indagate. In questo lavoro, le modificazioni strutturali e ultrastrutturali nei frutti, da piante con elefantiasi, sono state ricercate mediante le tecniche DRIFT, FT-Raman, NMR e SEM. Le principali variazioni riguardano la componente polisaccaridica.

Fusarium isolates obtained from Iran and Italy were identified by morphological characters and confirmed by using species-specific PCR assays. The genetic chemotyping for each strain, as a preliminary assessment for trichothecene production, was defined using PCR. Subsequently, artificial infection on durum wheat (cv. Normanno) was carried out in the greenhouse to study the pathogenicity and aggressiveness of Iranian, Italian and Syrian F. culmorum strains, the causal agent of crown and root rot of wheat. All F. culmorum strains from Iran and Italy belonged to the 3-acetyl-deoxynivalenol (3Ac-DON) chemotype, while F. culmorum strains from Syria, previously characterized, belonged to the 3Ac-DON and nivalenol (NIV) chemotypes. All of the strains were pathogenic and caused typical Fusarium crown rot (FCR) symptoms. Italian and Iranian strains showed similar mean aggressiveness levels (19.1 and 18.7% respectively), while the mean aggressiveness level for Syrian strains was 11.8%. There were statistically significant differences among the strains. Two Italian strains, F383 and F1126, had the greatest level of aggressiveness while FC9 (Italian) and F961 (Syrian) were the least aggressive strains. No significant differences relating to agro-ecological origin were detected among Iranian, Italian and Syrian strains. This is the first genetic chemotyping characterization and comparison of F. culmorum strains, isolated from different agro-ecological countries, Iran, Syria (Middle East) and Italy (Europe), which has estimated their potential for producing mycotoxins, and the aggressiveness levels of F. culmorum for development of FCR. These results support the increasing concerns about the risk of FCR in many wheat producing countries, particularly in Iran and Syria.