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Zymoseptoria tritici, a globally distributed pathogen, is responsible of Septoria tritici blotch (STB), one of the most damaging wheat diseases. In Italy the incidence of STB has increased during the past few years. The presence of Z. tritici on flag leaves of susceptible durum wheat plants, cultivar San Carlo, after a single artificial inoculation with two inoculum concentrations at different vegetative stages has been evaluated in the plain of Bologna (North of Italy), in a two year field study (2012–2013). The pathogen presence was also assessed in natural infection conditions after a fungicide application in the second year (2013). The results obtained, by visual examination (Incidence, Disease Severity) and DNA quantification by Real time PCR, demonstrated that BBCH 39 (flag leaf stage) is the most susceptible vegetative stage, independently of inoculum concentration and climatic conditions. A good correlation between Disease Severity and DNA quantity was observed in either sampling methods, entire flag leaves and flag leaf discs. Thereafter the most suitable period to obtain the best crop protection with only one fungicide treatment is the flag leaf stage.

Root and crown rot of wheat, caused by Fusarium culmorum (Fc), is a serious disease worldwide, particularly in Iran. Currently, the mechanisms underlying resistance to Fusarium-caused diseases are still unknown. Methyl jasmonate (MeJA) has been identified as a vital cellular regulator, and the effect of exogenous MeJA application during wheat-Fc interaction has not been studied previously at the molecular level. This study, using real-time quantitative PCR, was carried out to determine the expression of seven host defense-associated genes consisting of PR3, PR4, PR5, TaPERO, LOX, PAL and cytochrome P450 gene (CYP709C1) at 48, 72 and 96 h after Fc-inoculation (hai) and to investigate the relationship between the induced resistance by MeJA application and the gene expression patterns. The results showed that several genes were induced earlier (48 hai) and to higher levels in the resistant cv. Sumai3 than in susceptible cv. Falat. Many Fc-induced genes were also activated and induced by MeJA particularly during the later stages of infection; however, in contrast to defense-gene induction by the pathogen, there was not a general trend of higher induction in Sumai3 compared to Falat following this chemical treatment. The chemically induced protection significantly reduced the development of necrotic symptoms in both cultivars over a 3-week period after inoculation; however, this reduction was greater in Falat than in Sumai3 relative to the controls. Surprisingly, the expression of these genes was also expressed in crown tissue that had not yet been in contact with the fungus, signifying that a form of systemic response was taking place in this interaction. This is the first work reporting the effect of timing application of MeJA during Fc infection and comparing the defense-related gene expression between root and crown tissues of wheat genotypes. Moreover, soil-drench application of MeJA resulted in strong induction, verifying the success of this application method in systemically activating JA signaling for the first time. These results provided important intimations for designing strategies to curtail diseases caused by Fusarium.

Wheat is one of the most important crops in Syria, for both local consumption and export commodity and can be infected by Fusarium Head Blight (FHB) a world-widespread disease. Fusarium Head Blight reduces yield, grain quality and causes accumulation of deoxynivalenol (DON). The most promising and effective management strategy is to avail cultivars resistant to FHB. Ten Syrian durum wheat cultivars and "Simeto", one of the most susceptible Italian cultivars, were artificially infected, under growth chamber and field conditions. They were inoculated with Syrian and Italian strains of Fusarium culmorum, one of the main agents of FHB, to screen their tolerance toward FHB infection, FHB spread, kernel infection and mycotoxin levels. Jory was the most tolerant cultivar in the growth chamber and field, while Sham 9, was the most susceptible.

Fusarium pseudograminearum, F. culmorum and F. graminearum are the most important fusarium crown rot (FCR) causal agents. They have the common ability to biosynthesize deoxynivalenol (DON). To elucidate the behaviour of each of the three species, a comparative study was carried out to investigate symptom progression, fungal systemic growth and translocation of DON following stem base inoculation of soft wheat. FCR symptoms were mainly localized in the inoculated area, which extended up to the second node for all inoculated species. Only the most aggressive strains caused symptoms up to the third node. Real-time quantitative PCR showed that fungal colonization reached the third node for all the tested species, but a low percentage of plants showed colonization above the third node following inoculation with the most aggressive strains. Fungal growth was detected in symptomless tissues but none of the three species was able to colonize as far as the head tissues. However, even if the pathogens were not detected in the heads, DON was detected in head tissues of the plants inoculated with the most aggressive strains. These results demonstrate that F. pseudograminearum, F. culmorum and F. graminearum, under the same experimental conditions, follow a similar pattern of symptom progression, fungal colonization and DON translocation after stem base infection. Differences in the extent of symptoms, fungal colonization and mycotoxin distribution were mainly attributable to strain aggressiveness. These findings provide comparative information on the events following infection of the stem base of wheat by three of the most important FCR casual agents.

Wheat is one of the main crops in Mediterranean countries, and its cultivation has an important role in the Syrian economy. In Syria, Fusarium head blight (FHB) has not been reported so far. Mycological analysis of 48 samples of wheat kernels collected from cultivation areas with different climatic conditions were performed in 2009 and 2010. Fungal isolates were identified at the genus level morphologically; Fusarium species were characterized morphologically and by species-specific PCR. The most frequent fungal genera found were Alternaria spp. and Cladosporium spp., with frequencies of 24.7% and 8.1%, respectively, while the frequency of Fusarium spp. was 1.5% of kernels. Most frequent Fusarium species were F. tricinctum (30% of all Fusarium isolates), F. culmorum (18%), F. equiseti (14%) and F. graminearum (13%). The mycotoxin production potential of selected Fusarium isolates was assessed by HPLC-MS analysis of rice cultures; chemotyping by PCR was carried out for comparison. All six F. graminearum strains tested produced small amounts (100 mg/kg); four strains produced NIV and six strains produced deoxynivalenol (DON) and 3-acetyl-deoxynivalenol (3Ac-DON). PCR chemotyping lead to an oversimplified picture, because all 3Ac-DON chemotype strains produced more DON than 3Ac-DON; furthermore, the strongest NIV producers produced significant amounts of DON. All tested strains of F. culmorum, F. graminearum, F. pseudograminearum (two strains) and most F. equiseti strains (five of six strains) produced zearalenone. Grains of durum wheat were more frequently colonized by Fusarium spp. than grains of soft wheat. Incidence of Fusarium spp. in irrigated fields was higher than in rainfed fields. The incidence of Fusarium strains producing mycotoxins raises concerns about the risk of Fusarium head blight to Syria and its consequences for public health. peerReviewed

Fusarium culmorum is a soilborne fungal pathogen, agent of crown and root rot disease (FCRR), responsible of major economic losses in wheat plants. This host-pathogen interaction, following methyl jasmonate (MeJA) application at the beginning of the necrotrophic stage of infection, has not been previously studied at molecular level. In this study, using real-time quantitative PCR, the emerging role of MeJA in the basal resistance of two bread wheat cultivars against F. culmorum has been investigated. MeJA treatment was dispensed 6 hours after pathogen inoculation (6 hai) to detect the defense response at the beginning of the necrotrophic stage. The expression of phenylalanine ammonia-lyase (PAL), lipoxygenase (LOX), cytochrome P450 (CYP709C1) genes and of some pathogenesis related (PR) genes, including PR3, PR4 and PR9, was examined in both root and crown tissues of the susceptible wheat cultivar Falat and the tolerant cultivar Sumai3. The pathogen responsive defense genes were induced in both cultivars, with a higher level of induction in Sumai3 than in Falat. MeJA treatment reduced the symptoms in cv Falat, whereas no significant effects have been detected in cv Sumai3. In fact, MeJA treatment caused a striking difference in defense gene induction. The genetic change was present in root and crown tissues of both wheat cultivars, demonstrating a systemic signaling pathway. The chemically induced protection correlated with induction of the F. culmorum-responsive genes supports a possible role of jasmonate signaling in regulating basal resistance in wheat-F. culmorum interaction.

Dipartimento di Scienze Agrarie e Ambientali, Universita degli Studi di Perugia, Borgo XX Giugno, 74, 06121 Perugia, Italy (Received on June 24, 2011; Revised on October 13, 2011; Accepted on October 16, 2011)Chemotype composition of Fusarium graminearumstrains, isolated from durum wheat kernels fromnaturally FHB infected fields in Northern and CentralItaly, was investigated by multiplex PCR. The differentclimatic and environmental conditions of the twoexamined areas separated by the Apennines affected thecomposition of chemotypes. 15Ac-DON chemotype waspredominant in both the sub areas. Nivalneol chemo-type was more frequent in the warmer sub area.Keywords :chemotype, durum wheat, Fusarium graminearum,Fusarium head blightFusarium graminearum (teleomorph Gibberella zeae(Schwein.) Petch.) is the major pathogen responsible ofFusarium head blight (FHB), an economically crucial andcomplex etiology disease on cereal crops worldwide(Goswami and Kistler, 2004). FHB has received moreattention because of its effect on yield (Parry et al., 1995),grain quality (Liggitt et al., 1997) and grain contaminationby mycotoxins (Visconti et al., 2000). FHB resistantcultivars are considered one of the solutions for the problemrelated to mycotoxin contamination in wheat grains (Lemmenset al., 2004), but unfortunately to date no resistant cultivar iscommercially available for durum wheat. Most attention inthe analysis of grain affected by FHB was placed oncontamination by deoxynivalenol (DON), acetylated formsof DON (3Ac-DON and 15Ac-DON) and nivalenol (NIV).DON is a mycotoxin that disturbs and/or inhibits DNA,RNA and protein synthesis by binding to the ribosomalpeptidyltransferase site leading to a decrease of cell pro-liferation (Shifrin and Anderson, 1999). It is also known asvomitoxin and it is responsible for hemorrhagic andanorexic syndromes, neurotoxic and immunotoxic effectsin mammals (Visconti et al., 2004). DON contaminationlevels in food and feed were found to be much higher thanthose observed for NIV (Boutigny et al., 2011), beingprobably the most negligible toxin due to the small amountusually detected (Yazar and Omurtag, 2008), but withconsistent levels in many Asian countries, New Zealandand Brazil (Placinta et al., 1999). However, NIV has shownto have a higher toxicity than DON, for example, in humanblood cells (Minervini et al., 2004). This toxin has alsoshown higher activity than DON in inhibiting DNA, and itmay account for various toxic phenomena such as inductionof cell death (Poapolathep et al., 2002). Based on the production of type B trichothecenes, DONand NIV, three F. graminearum chemotypes have beendescribed: 3Ac-DON, 15Ac-DON and NIV. Chemotypeidentification is broadly used to characterize F. graminearumfor its toxigenic potential (Pasquali et al., 2009). There wasa correlation between the presence of F. graminearumchemotype and wheat grain mycotoxin content. DON andNIV contents can be successfully predicted by quantifyingthe fungal biomass of DON and NIV producers with a real-time PCR quantification method (Brandfass and Karlovsky,2006; Burlakoti et al., 2007; Pasquali et al., 2009). The dominant chemotypes of F. graminearum varywithin geographical areas, i.e. different countries and/orcontinents (Prodi et al., 2009b), but some host preferencemay affect the composition of chemotypes of F. grami-nearum population. Within the same country, the differentgeographical areas (i.e. plain, mountains, valleys, etc.) anddistances from the sea, may also affect the composition ofchemotypes of a fungal population. Mountains may play animportance role as natural obstacles by inhibiting the

During 2011, Fusarium rot of stored garlic was detected on bulbs of ‘Aglio Bianco’ (white garlic) in Piacenza, Ferrara and Rovigo districts. Bulbs, harvested in July, were asymptomatic. During conservation in the drying sheds, approximately thirty percent of bulbs appeared emptied and softened. Fusarium proliferatum was consistently recovered from infected bulbs. The morphological identification was confirmed by Translation Elongation Factor 1-alpha gene sequencing. Koch postulates were checked through pathogenicity tests. The disease has already been reported in Serbia, Germany, Spain, United States, China and India, but to our knowledge, this is the first report of F. proliferatum garlic bulb rot in Italy.

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 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

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.