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Rusts are a noxious group of plant diseases affecting major economically important crops. Crop protection is largely based on chemical control. There is a renewed interest in the discovery of natural products as alternatives to synthetic fungicides for control. In this study we tested two fungal metabolites, namely cyclopaldic acid and epi-epoformin, for their effectiveness in reducing early stages of development of two major rust fungi from the genera Puccinia and Uromyces, P. triticina and U. pisi. Spore germination and appressorium formation were assessed on pretreated detached leaves under controlled conditions. Cyclopaldic acid and epi-epoformin were also tested in infected plants in order to evaluate the level of control achieved by treatments both before and after inoculation.

Trabajo presentado en la International Conference Advances in grain legume breeding, cultivations and uses for a more competitive value-chain, celebrada en Novi Sad (Serbia) el 27 y 28 de septiembre de 2017., Pea weevils (Bruchus pisorum) is a pest of the field pea (Pisum sativum) of great economic importance. Recently, pea accessions have been reported to reduce seed infestation, and/or larval development. Pods and seeds from these accessions were collected to check constitutive metabolites able to block the egg lying on pods (seed infestation) while pea seeds to check metabolites hampering larval development. Pea pods and seeds were lyophilized in order to evaluate metabolites that may be involved in pea weevil infestation. Standard method for metabolomics analysis was carried out on lipophilic and hydrophilic metabolites extracted, then compared to find a biomarker of resistance in pea. In this communication the studies aimed to identify metabolites responsible for antixenosis and/or antibiosis in pea resistant accessions to weevils will be discussed.

Trabajo presentado en el 15th Congress of the Mediterranean Phytopathological Union (Plant health sistaining Mediterranean ecosystems), celebrado en Córdoba (España) del 20 al 23 de junio de 2017., Foliar diseases caused by biotrophic pathogens, such as rusts and powdery mildews, are major limiting factors in legume and cereal production worldwide. Crop protection is largely based on chemical control, although there is renewed interest in the discovery of natural products as alternatives to synthetic fungicides., This research was supported by FP7-ARIMNet-MEDILEG and AGL2014-52871 projects and Programme STAR (A.C.) financially supported by UniNa and Compagnia di San Paolo, Italia.

Trabajo presentado en la International Conference Advances in grain legume breeding, cultivations and uses for a more competitive value-chain, celebrada en Novi Sad (Serbia) el 27 y 28 de septiembre de 2017., Fusarium oxysporum f. sp. pisi (Fop) is a ubiquitous soil pathogen reducing field pea (Pisum sativum) yield worldwide. Monogenic resistance have been already described and successfully used in breeding. However, monogenic resistance is at risk of breakdown by the constant evolution of the pathogen. To improve the durability of resistance, the genetic base of resistance should be broadened and a better knowledge on the defense mechanisms efficient against Fop should be gathered. To this aim, we identified several Fop-resistant Pisum spp. accessions and characterized the underlying defense mechanisms. A first study on pre-penetration mechanism revealed that the root exudate of three accessions inhibited Fop germination. Further analyses indicated that this pre-penetration mechanism was mainly mediated through the constitutive secretion of pisatin, the main pterocarpan pea phytoalexin. A second study focused on post-penetration defense mechanism at the cellular level, showing that involvement of three main mechanisms, namely papilla formation, cell walls strengthening and accumulation of phenols and carbohydrates. These studies highlight that pea accessions combined several strate gies to delay and efficiently prevent disease development which offer interesting opportunities for breeding.

Trabajo presentado en el 15th Congress of the Mediterranean Phytopathological Union (Plant health sistaining Mediterranean ecosystems), celebrado en Córdoba (España) del 20 al 23 de junio de 2017., Root exudates are important regulators of plant rhizospheres. They can modulate the composition and dynamics of soil micro-organisms and participate in the dialogue between plants and microorganisms. They are known to modulate germination and growth of soil microorganisms. As such, they may contribute to crop resistance to soil-borne pathogens., This research was supported by the European KBBE project LEGATO (FP7-KBBE2013.1.2-02-613551), and the Spanish national project AGL2014-52871-R from the Spanish Ministry of Economy and Competitiveness (MINECO), and was co-financed by the European fund for regional development (FEDER). NR holds a Ramón y Cajal postdoctoral position from MINECO.

Trabajo presentado en la 4th Annual Conference of the COST action SUSTAIN, celebrada en Bled (Slovenia) del 1 al 3 de marzo de 2017., Ascochyta and Botrytis species cause major diseases on legume crops. Fungi from both genera are well known phytotoxins producers. Based on collaboration between CSIC and Univ. Naples necrotrophic effectors produced by Didymella pinodes and Botrytis fabae have been identified and characterized chemically and biologically. Their use in resistance screenings are being tested and will be critically discussed.

Trabajo presentado en la International Conference Advances in grain legume breeding, cultivations and uses for a more competitive value-chain, celebrada en Novi Sad (Serbia) el 27 y 28 de septiembre de 2017., Rusts and powdery mildews are major limiting factors worldwide for many crops, including legumes. Despite of continued efforts to develop cultivars with high level of genetic diseases resistance, fungicides are, currently, the mainstay control method and a wide range of synthetic compounds are widely used. However, a renewed interest in the discovery of natural products as alternatives to synthetic fungicides application is recently emerged. Considering that spore germination and fungal penetration are key phases for the initial development of biotrophic plant pathogens, a further approach proposed for their management could be the use of natural metabolites produced by plants and fungi as pathogen inhibitors in these pre-penetration stages. With this aim we studied potential application for disease management of eight fungal and plant metabolites. Their inhibitory effect on early stages infection was studied on 4 rusts and 2 powdery mildew species. Results will be presented and critically discussed., This research was financially supported by AGL2014-52871 projects and Programme STAR financially supported by UniNa and Compagnia di San Paolo, Italy.

Although fungi produce highly structurally diverse metabolites, many of which have served as excellent sources of pharmaceuticals, no fungi-derived agent has been approved as a cancer drug so far. This is despite a tremendous amount of research being aimed at the identification of fungal metabolites with promising anticancer activities. This review discusses the results of clinical testing of fungal metabolites and their synthetic derivatives, with the goal to evaluate how far we are from an approved cancer drug of fungal origin. Also, because in vivo studies in animal models are predictive of the efficacy and toxicity of a given compound in a clinical situation, literature describing animal cancer testing of compounds of fungal origin is reviewed as well. Agents showing the potential to advance to clinical trials are also identified. Finally, the technological challenges involved in the exploitation of fungal biodiversity and procurement of sufficient quantities of clinical candidates are discussed, and potential solutions that could be pursued by researchers are highlighted.

A new 3-substituted-5-diazenylcyclopentendione named kongiidiazadione was isolated from culture filtrates of Diaporthe kongii, associated with stem cankers on sunflower in Australia. Kongiidiazadione was characterized by spectroscopic (essentially nuclear magnetic resonance [NMR] and high-resolution, electrospray ionization, mass spectrometry [HRESIMS]) methods as (-)-5-diazenyl-3-hydroxymethyl-cyclopent-3-en-1,2-dione. The stereochemistry of the diazenyl group was determined by IR spectroscopy, while the (R) absolute configuration at C(5) was assigned by computational analysis of its electronic circular dichroism (ECD) spectrum. When assayed on leaf disks of different plant species at 5 mM, the kongiidiazadione had a differential impact, causing clear necrosis, in particular to Helianthus annuus. Moreover, kongiidiazadione proved to have a weak antibacterial activity against gram-positive Bacillus amyloliquefaciens.