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The presence of ear rots in maize caused by Aspergillus flavus that are also associated with the production of aflatoxins has evolved into an increasing problem over the last few years. Since no commercial biological control products are still available to control A. flavus in maize in Europe, this study targets to the evaluation of six biopesticides/biostimulants (Botector®, Mycostop®, Serenade Max®, Trianum®, Vacciplant®, and zeolite) for the control of A. flavus and the derived aflatoxins in in vitro and maize field bioassays. Mycostop®, Serenade Max®, Vacciplant®, and zeolite reduced significantly A. flavus conidia production by 38.8–63.1%, and most of them were able to reduce aflatoxin B1 (AFB1) production in laboratory studies. Mycostop®, Trianum®, and Botector® were effective in reducing AFB1, in vitro. In the field, Mycostop® and Botector® treatments resulted in significant reduction of the disease severity (16.5 and 21.9%, respectively) and decreased significantly AFB1 content in maize kernels by 43.05 and 43.09%, respectively. For the first time, these results demonstrated the potential of commercial non-chemical products to suppress disease symptoms and aflatoxin content caused by A. flavus in maize under laboratory and field conditions.

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Mycotoxins represent a serious risk for human and animal health. Οchratoxin A (OTA) is a carcinogenic mycotoxin produced by A. carbonarius that constitutes a severe problem for viticulture. In this study, we investigate the development of novel detection and on-line monitoring approaches for the detection of OTA in the field (i.e. out of the chemical laboratory) using advanced molecular sensing. Both stand-alone and hyphenated mass spectrometry (MS) based systems (e.g. Time-of-Flight ToF–MS and gas chromatography GC combined with MS) and compact portable membrane inlet MS (MIMS) have been employed for the first time to detect and monitor volatile emissions of grape berries infected by the fungus Aspergillus carbonarius. In vacuo (electron impact—EI) and ambient ionisation (electrospray ionisation—ESI) techniques were also examined. On-line measurements of the volatile emissions of grape berries, infected by various strains of A. carbonarius with different toxicity levels, were performed resulting in different olfactory chemical profiles with a common core of characteristic mass fragments, which could be eventually used for on-site detection and monitoring allowing consequent improvement in food security.

Malt barley is one of the promising crops in Greece, mainly due to high yields and contract farming, which have led to an increase in malt barley acreage. Net form net blotch (NFNB), caused by Pyrenophora teres f. teres, and barley leaf scald, caused by Rhynchosporium secalis, are among the most important barley diseases worldwide and particularly in Greece. Their occurrence in malt barley can exert a significant negative effect on malt barley grain yield and quality. An experimental trial across two growing seasons was implemented in Greece in order (i) to estimate the epidemiology of NFNB and leaf scald in a barley disease-free area when the initial inoculation of the field occurs through infected seeds, (ii) to explore the spatial dynamics of disease spread under the interaction of the nitrogen rate and genotype when there are limited sources of infected host residues in the soil and (iii) to assess the relationship among the nitrogen rate, grain yield, quality variables (i.e., grain protein content and grain size) and disease severity. It was confirmed that both NFNB and leaf scald can be carried over from one season to the next on infected seed under Mediterranean conditions. However, the disease severity was more pronounced after the barley tillering phase when the soil had been successfully inoculated, which supports the hypothesis that the most important source of primary inoculum for NFNB comes from infected host residue. Increasing the rate of nitrogen application, when malt barley was cultivated in the same field for a second year in a row, caused a non-significant increase in disease severity for both pathogens from anthesis onwards. However, hotspot and commonality analyses revealed that spatial and genotypic effects were mainly responsible for hiding this effect. In addition, it was found that the effect of disease infections on yield, grain size and grain protein content varied in relation to the genotype, pathogen and stage of crop development. The importance of crop residues in the evolution of both diseases was also highlighted.

Olive trees (Olea europaea L.) are among the most important fruit tree crops grown in Albania, covering an estimated 8% of the arable land of this country. The highest amount of olive production in Albania is concentrated in the coastal districts of Fier, Berat, Elbasan, Lezha, Tirana, Kruja and Vlora, all with Mediterranean climate conditions. Anthracnose is the main disease of olive fruit caused by different Colletotrichum spp. primarily belonging to two complexes, C. acutatum sensu lato (s.l.) and C. gloeosporioides s.l. (Cacciola et al. 2012; Schena et al. 2014.). On July 2018, field observations of about 50 olive trees in the Ishull Shengjin Lezhe Region (54% prevalence), 1 km away from the coast showed severe symptoms of mummified olive fruits in about 20 to 40% disease incidence and 30% disease severity of the Italian table olive cv. Frantoio trees resulting in premature fruit drop or mummification. The causal agent was isolated directly from infected fruits on potato dextrose agar and Rose Bengal nutrient media. Microscopic examinations of five single spore isolated fungal colonies showed acervuli with typical conidia of the genus Colletotrichum that were aseptate, straight, hyaline, subcylindrical with rounded ends and 12.3 to 22.1 µm long (mean = 17.4 µm) and 2.5 to 7.3 µm wide (mean = 5.9 µm) (n= 50 conidia) (Damm et al. 2012). To identify the fungal species, DNA from two single-spore isolates (Col-3-ALB and Col-9-ALB) isolated from fruits was extracted, and six genes were amplified (ITS, GAPDH, CHS-1, HIS3, ACT, and TUB2) using the primers reviewed in Damm et al. (2012). PCR products were sequenced, and BLAST analysis showed 100% identity to C. acutatum for both isolates (GenBank accession nos. for Col-9-ALB MT218337 [ITS1-5.8-ITS2], MT274748 [CHS-1], MT274749 [HIS3], MT274750 [GAPDH], MT274751 [TUB2], and MT274752 [ACT]). Phylogenetic analysis using the concatenated sequences of Col-9-ALB, the type species of C. acutatum (112996), a previously identified published Greek C. acutatum isolate (O9) and three C. godetiae strains confirmed the identification of Col-9-ALB as C. acutatum. Pathogenicity tests were performed in the laboratory to confirm the ability of C. acutatum isolates to cause disease on olive drupes. Fruits were surface disinfected with 0.1% NaClO for 3 min and rinsed with ddH2O. Artificial inoculations with the two above isolates were performed by spraying 24 olive fruits per isolate cv. Kalamon (eight olive fruits per replication) with a spore suspension (106 conidia/ml). Olive fruits sprayed with sterilized water served as untreated control. After inoculation, olive fruits were placed in closed sterile plastic boxes and kept at 26°C with a 12-h photoperiod. First rot symptoms and formation of acervuli by the pathogen were initiated 3 days after inoculation. Eight days post-inoculation, all treatments exhibited typical anthracnose symptoms similar to those observed in olive orchards (extensive fruit rot). To fulfil Koch’s postulates, C. acutatum was re-isolated from 10 random symptomatic olive fruits/isolate and their identity was confirmed from all samples. To our knowledge, this is the first report of C. acutatum causing fruit rot on olive trees in Albania. It is important to further study the epidemiology for the disease under local climate conditions and on different olive cultivars in order to develop effective management strategies for this very destructive disease of olive.

In the last two decades grapevine trunk diseases (GTDs) have emerged as the most significant threat for grapevine sustainability worldwide. The tracheomycotic fungus Phaeomoniella chlamydospora (Pch) is the predominant GTD-associated species and cannot be controlled with available chemicals. In the present study, we evaluated the effectiveness of two microbial strains (Paenibacillus alvei K165 and Fusarium oxysporum F2) against Pch in grapevine. In vitro bioassays, performed in a growth culture medium simulating the xylem environment, indicated that F2 decreased Pch growth and sporulation, whereas K165 did not have any effect on Pch growth. In planta experiments revealed that root-drench and stem-puncture application of K165 and F2 reduced the endophytic relative DNA amount of Pch by 90% and 82%, respectively, compared to controls. However, wood discoloration, the typical symptom of Pch infection, was not reduced in the F2 treated grapevines. Nevertheless, the F2 treated grapevines harbored higher lignin levels compared to mocks, as it was also done by K165. Therefore, F2 and K165 have the potential to be used as biocontrol agents against Pch in grapevines.