Le leguminose sono da state sempre in Puglia di primaria importanza, tanto nell'agricoltura che per l'alimentazione. Negli ultimi decenni c'era stato un lento declino di queste colture, con un progressivo decremento delle superfici coltivate. Con l'avvento della nuova PAC le superfici coltivate sono nuovamente e grandemente aumentate, dovendo le aziende ottemperare l'obbligo della diversificazione colturale; spesso,trattandosi di zone non irrigue, le leguminose costituiscono la più importante, se non l'unica, possibilità di alternanza con i cereali, tra i quali il frumento duro e l'orzo sono i predominanti. Tali nuove situazioni colturali stanno comportando, e lo faranno sempre più in futuro, la comparsa di problemi sopiti o sottovalutati, come la presenza della pericolosissima specie infestante parassita Orobanche crenata Forsk. Una breve panoramica sulla dannosità di questa specie e le attuali e future possibilità di contenimento vengono illustrate.

Host root derived signals trigger the germination of seeds of obligate root parasitic weeds. Among these, strigolactones (SLs), a class of plant hormones, are the major natural germination stimulants in the rhizosphere. The early growth stages of parasitic plant development - such as seed germination, host attachment, and tubercle development - are key stages for establishing a successful parasitic interaction and are therefore ideal targets for controlling root parasitic weeds. Soil microorganisms and natural bioactive compounds interfering with these early stages of the parasite life cycle could be used as novel tools for management strategies. Our knowledge on the mechanism of SLs as signaling molecules during specific interactions in the rhizosphere is currently limited to arbuscular mycorrhizal fungi and parasitic plant seeds. By contrast, the role of plant secreted SLs in regulating the growth and development of plant pathogenic fungi remains controversial. Root colonizing fungi can influence crop productivity either negatively by causing disease, or positively by enhancing plant growth. The production of plant hormones and growth regulators appears to be an important mechanism by which fungal endophytes improve plant growth and yield under stressful conditions. Fusarium oxysporum (F. o.) is a cosmopolitan species that survives in the soil as a saprophyte by thriving on dead or decaying organic matter. Some representatives also behave as plant pathogens causing vascular wilt disease in different crops, or as biocontrol agents, both as endophytes inducing systemic resistance and as enhancers of soil suppressiveness. F. o. has been suggested to be able to detect and degrade SLs, thereby preventing seed germination of parasitic weeds. Previous studies revealed that F. o. hyphae can sense and reorient their growth towards a variety of chemical signals including compounds from the host plant2. To understand how F. o. senses and degrades SLs, we used a quantitative chemotropism assay on agar plates with different synthetic and natural SLs (e.g. GR24, strigol, 5-deoxystrigol and 4-deoxyorobanchol) as chemoattractant signals. We found that F. o. is able to chemotropically sense SLs, and that this process requires elements of a conserved fungal mitogen activated protein kinase (MAPK) signaling cascade.

A new tetrasubstituted indolylidenpyrandione named colletopyrandione (1), together with a tetrasubstituted chroman- and a tetrasubstituted isocroman-3,5-diol, named colletochlorins G and H (2, 3), respectively, were isolated from the culture filtrates of the fungus Colletotrichum higginsianum together with the already known colletochlorin A, 4-chloroorcinol, colletopyrone and colletochlorins E and F. Colletopyrandione and the two new colletochlorins (G and H) were characterized as (Z)-3-(3-hydroxy-3-methylindolin-2-ylidene)-5,6-dimethyl-pyran-2,4-dione, 8-chloro-2,2,7-trimethyl-chroman-3,5-diol and 8-chloro-1,1,7-trimethyl-isochroman-3,5-diol, respectively, by spectroscopic (NMR and HRESIMS) methods. The relative configuration of 1 was assigned by X-ray diffractometric analysis. Colletopyrandione was isolated as scalemic mixture and the absolute configuration of the most abundant enantiomer was assigned by ECD and VCD spectra combined with quantum-mechanical calculations. Assayed in several biological systems, colletopyrandione showed a modest phytotoxic activity, associated to a complete lack of toxicity towards off-target organisms.

A new tetrasubstituted pyran-2-one and a new dihydrobenzofuran, named colletochlorins E and F (1 and 2), were isolated from the culture filtrates of the fungus Colletotrichum higginsianum together with the already known colletochlorin A, 4-chloroorcinol and colletopyrone. Colletochlorins E, the main metabolite, and F were characterized by spectroscopic (NMR, HRESIMS) and chemical methods as 3-[7-chloro-4-hydroxy-2-(1-hydroxy-1-methylethyl)-6-methyl-2,3-dihydro-benzofuran-5-ylmethyl]-4-hydroxy-5,6-dimethyl-pyran-2-one, and 7-chloro-2-(1-hydroxy-1-methylethyl)-6-methyl-2,3-dihydrobenzofuran-4-ol. The absolute configuration 2?S of 1 was deduced by X-ray diffractometric analysis while that 2S of 2 was deduced by comparison of its NMR and CD data with those of 1. When assayed by leaf puncture on Sonchus arvensis and tomato leaves, 2 caused quite large necrosis (wider than 1 cm) while 4-chloroorcinol proved to be the most active compound. These results were confirmed to those obtained in the assay on Lemna minor and on Phelipanche ramosa seed germination. Furthermore, 1, colletochlorin A and colletopyrone were less and modestly active in the last assay, respectively. Interestingly, the phytotoxicity was not associated to an antibiotic activity while only 4-chloroorcinol, colletochlorin F exhibited zootoxic activity.

Ailanthus altissima (Mill.) Swingle (commonly named tree of haven, family: Simaroubaceae) is a very dangerous invasive plant species. The invasiveness of this dioecious species is due to its ability to reproduce, equally well, both by seed (one plant can produce thousands of "flying" samaras) and asexually (its extended and vigorous root system generates numerous suckers and progeny plants). The species is able to adapt to any type of soil and water regime. It spreads everywhere in urban and sub-urban areas, on roadsides, railways and ruins, in uncultivated or abandoned areas, gardens and green spaces. A. altissima plants reach the heart of natural areas causing severe ecological effects. Plants form highly dense stands outcompeting native species and reducing their growth. Thus this species represents a serious threat both in natural and anthropic areas.The management of A. altissima is very difficult. The most common methods include manual, mechanical and chemical control. Hand pulling can be carried out only on very young seedlings before the root system has developed. Mechanical removal (cut) is the most used technique in public areas but proved to be costly and quite ineffective, as it induces a faster development of suckers and resprouting shoots. Moreover, in urban and archeological areas the use of mechanical equipment can be very dangerous or even not practicable. Spray treatments of herbicides are frequently not allowed in urban and natural areas due to health and environmental risks. The Alta Murgia National Park is a very wide Park (over 68,000 ha) located in the Apulia Region (Southern Italy). It is a Site of Community Importance (SCI) and a Special Protection Area (SPA) within the EU Natura 2000 network. Within the Park, A. altissima is the most spread invasive plant species, and it is considered one of the most serious threat for the biodiversity. A project named "LIFE Alta Murgia" was funded in 2013 by the European Commission within the LIFE+ Framework, aimed at eradicating A. altissima from the Alta Murgia National Park by using innovative and eco-friendly control techniques, based on a minimized use of effective herbicides with environmentally friendly stem applications (e.g. stem injection, cut stump, spaced cut). In order to accurately take a census, map and quantify the infestation in the whole park, plan the interventions, manage the control program and check the progresses of the management practices, a ad hoc software was initially developed.In the present communication the procedures used and the results obtained in the weed mapping will be shown. Moreover, the first results regarding the control treatments and their effectiveness will be presented.

Cavoxin is a tetrasubstituted phytotoxic chalcone and cavoxone is the correponding chroman-4-one, bothproduced in vitro by Phoma cava, a fungus isolated from chestnut. Cavoxin showed biofungicidepotential against fungal species responsible of food molding. Therefore, cavoxin has potential to beincorporated into biopolymer to generate a so called "intelligent food packaging". To reach this objectivethe large scale production of cavoxin by P. cava fermentation need to be optimized. A rapid and efficientmethod for cavoxin analysis, as well as of cavoxone, in the fungal culture filtrates and thecorresponding organic extracts is the first experimental step. Thus, a HPLC method was developed andapplied to quantify cavoxin and cavoxone production in two different fungal culture conditions. Theanalysis proved that cavoxin production in stirred culture filtrates is significantly higher than in staticones.

Among the woody invasive alien species colonizing non-crop areas, Ailanthus altissima (Tree ofhaven) is one of the worst and most damaging weeds. It spreads everywhere in urban, suburban andnatural areas creating dense stands and causing much damage including biodiversity loss. Its controlis very difficult because of its fast growth, its capability of regenerating as 'suckers' from buds on theroots and stem after mechanical interventions, and its production of large numbers of seeds that areeasily scattered in the environment. Within the "LIFE Alta Murgia" Project, founded by the EuropeanCommission, aimed at eradicating A. altissima from the Alta Murgia National Park using innovativeand eco-friendly control techniques, the suitability of potential microbial biological agents wereexplored. Two fungal pathogens were isolated from diseased plants, identified, tested forpathogenicity and aggressiveness, and studied for the production of bioactive metabolites. The firstresults of the studies on the two fungal agents, including the chemical and biological characterizationof the metabolites and their potential as natural herbicides, are presented.

Fungal phytotoxins are natural secondary metabolites produced by plant pathogenic fungi during host-pathogen interactions. They have received considerable particular attention for elucidating disease etiology, and consequently to design strategies for disease control. Due to wide differences in their chemical structures, these toxic metabolites have different ecological and environmental roles and mechanisms of action. This review aims at summarizing the studies on the possible use of thesemetabolites as tools in biological and integrated weed management, e.g. as: novel and environmentally friendly herbicideslead for novel compounds; sources of novel mechanisms of action. Moreover, the limiting factors for utilizing those metabolites in practice will also be briefly discussed.

Le piante parassite rappresentano un mondo a parte nell'universo delle piante infestanti. Esse possiedono alcune caratteristiche biologiche, morfologiche, fisiologiche ed ecologiche che le rendono diverse da tutte le altre specie infestanti, e che influiscono grandemente sulle possibili strategie di gestione. In questa comunicazione viene brevemente illustrato il ciclo vitale delle piante parassite, con riferimento alle orobanche, e le prospettive di gestione.

A virulent strain of Diaporthe gulyae, isolated from stem cankers of sunflower and known to be pathogenic to saffron thistle, has been shown to produce both known and previously undescribed metabolites when grown in either static liquid culture or a bioreactor. Together with phomentrioloxin, a phytotoxic geranylcyclohexenetriol recently isolated from a strain of Phomopsis sp., two new phytotoxic trisubstituted ?-pyrones, named gulypyrones A and B (1 and 2), and two new 1,O- and 2,O-dehydro derivatives of phomentrioloxin, named phomentrioloxins B and C (3 and 4), were isolated from the liquid culture filtrates of D. gulyae. These four metabolites were characterized as 6-[(2S)2-hydroxy-1-methylpropyl]-4-methoxy-5-methylpyran-2-one (1), 6-[(1E)-3-hydroxy-1-methylpropenyl]-4-methoxy-3-methylpyran-2-one (2), 4,6-dihydroxy-5-methoxy-2-(7-methyl-3-methyleneoct-6-en-1-ynyl)cyclohex-2-enone (3), and 2,5-dihydroxy-6-methoxy-3-(7-methyl-3-methyleneoct-6-en-1-ynyl)cyclohex-3-enone (4) using spectroscopic and chemical methods. The absolute configuration of the hydroxylated secondary carbon of the 2-hydroxy-1-methylpropyl side chain at C-6 of gulypyrone A was determined as S by applying a modified Mosher's method. Other well-known metabolites were also isolated including 3-nitropropionic, succinic, and p-hydroxy- and p-methylbenzoic acids, p-hydroxybenzaldehyde, and nectriapyrone. When assayed using a 5 mM concentration on punctured leaf disks of weedy and crop plants, apart from 3-nitropropionic acid (the main metabolite responsible for the strong phytotoxicity of the culture filtrate), phomentrioloxin B caused small, but clear, necrotic spots on a number of plant species, whereas gulypyrone A caused leaf necrosis on Helianthus annuus plantlets. All other compounds were weakly active or inactive.

Two new diterpenoid alpha-pyrones, named higginsianins A (1) and B (2), were isolated from the mycelium of the fungus Colletotrichum higginsianum grown in liquid culture. They were characterized as 3-[5a,9b-dimethyl-7-methylene-2-(2-methylpropenyl)dodecahydronaphtho[2,1-b]furan-6-ylmethyl]-4-hydroxy-5,6-dimethylpyran-2-one and 4-hydroxy-3-[6-hydroxy-5,8a-dimethyl-2-methylene-5-(4-methylpent-3-enyl)decahydronaphthalen-1-ylmethyl]-5,6-dimethylpyran-2-one, respectively, by using NMR, HRESIMS, and chemical methods. The structure and relative configuration of higginsianin A (1) were confirmed by X-ray diffractometric analysis, while its absolute configuration was assigned by electronic circular dichroism (ECD) experiments and calculations using a solid-state ECD/TDDFT method. The relative and absolute configuration of higginsianin B (2), which did not afford crystals suitable for X-ray analysis, were determined by NMR analysis and by ECD in comparison with higginsianin A. 1 and 2 were the C-8 epimers of subglutinol A and diterpenoid BR-050, respectively. The evaluation of 1 and 2 for antiproliferative activity against a panel of six cancer cell lines revealed that the IC50 values, obtained with cells reported to be sensitive to pro-apoptotic stimuli, are by more than 1 order of magnitude lower than their apoptosis-resistant counterparts (1 vs >80 mu M). Finally, three hemisynthetic derivatives of 1 were prepared and evaluated for antiproliferative activity. Two of these possessed IC50 values and differential sensitivity profiles similar to those of 1.

Certain amino acids induce inhibitory effects in plant growth due to feedback inhibition of metabolic pathways. The inhibition patterns depend on plant species and the plant developmental stage. Those amino acids with inhibitory action on specific weeds could be utilized as herbicides, however, their use for weed control has not been put into practice. Orobanche minor is a weed that parasitizes red clover. O. minor germination is stimulated by clover root exudates. The subsequent seedling is an obligated parasite that must attach quickly to the clover root to withdraw its nutrients. Early development of O. minor is vulnerable to amino acid inhibition and therefore, a series of in vitro, rhizotron, and field experiments were conducted to investigate the potential of amino acids to inhibit O. minor parasitism. In in vitro experiments it was found that among a collection of 20 protein amino acids, lysine, methionine and tryptophan strongly interfere with O. minor early development. Field research confirmed their inhibitory effect but revealed that methionine was more effective than lysine and tryptophan, and that two successive methionine applications at 308 and 543 growing degree days inhibited O. minor emergence in red clover up to 67%. We investigated additional effects with potential to influence the practical use of amino acids against broomrape weeds, whether the herbicidal effect may be reversible by other amino acids exuded by host plants or may be amplified by inducing host resistance barriers against O. minor penetration. This paper suggests that amino acids may have the potential to be integrated into biorational programs of broomrape management.

Ascochyta lentis var. lathyri has recently been reported to be the causal agent of Ascochyta blight of grass pea (Lathyrus sativus), a disease characterized by the appearance of necrotic lesions of leaves and stems. Considering the novelty of the pathogen and the possible involvement of secondary metabolites in symptom appearance, a study was carried out to ascertain the capability of this fungus to produce bioactive metabolites. Some phytotoxic phenols were isolated from the culture filtrates of the fungus. In particular, two new phytotoxic metabolites, named lathyroxins A and B, were characterized by spectroscopic methods as 4-(2-hydroxy-3,3-dimethoxypropyl)phenol and 3-(4-hydroxyphenyl)propane-1,2-diol, respectively, and the R absolute configuration of C-2 of their 2-dimethoxy- and 2,3-diol-propyl side chain was assigned. Moreover, other well-known fungal metabolites, namely, p-hydroxybenzaldehyde, p-methoxyphenol, and tyrosol, were also identified. Lathyroxins A and B showed interesting phytotoxic properties, being able to cause necrosis on leaves and to inhibit seed germination and rootlet elongation. Moreover, both of the new metabolites had no effect against bacteria, arthropods, and nematodes.

A strain of the pathogenic fungus Ascochyta lentis isolated from lentil (Lens culinaris) was studied to ascertain its capability to produce bioactive metabolites. From the culture filtrates were found three new anthraquinone derivatives, named lentiquinones A (1), B (2), and C (3), and the known lentisone. From the mycelium, four known analogues were identified, namely pachybasin (in larger amount), ?-hydroxypachybasin, 1,7-dihydroxy-3-methylanthracene-9,10-dione, and phomarin. Lentiquinones A-C were characterized by spectroscopic methods as 3,4,6-trihydroxy-8-methyl-2H-benzo[g]chromene-5,10-dione, 2,3,4,5,10-pentahydroxy-7-methyl-3,4,4a,10-tetrahydroanthracen-9(2H)-one, and its 2-epimer, respectively, and the relative configuration of the two latter compounds was deduced by X-ray diffraction data analysis. The absolute configuration of lentiquinones B and C was determined as (2R,3S,4S,4aS,10R) and (2S,3S,4S,4aS,10R), respectively, by electronic circular dichroism (ECD) in solution and solid state, and TDDFT calculations. When tested by using different bioassays, the novel compounds showed interesting activities. In particular, applied to punctured leaves of host and nonhost plants, the three new compounds and lentisone caused severe necrosis, with lentiquinone A being the most active among the new metabolites. On cress (Lepidium sativum), this latter compound proved to be particularly active in inhibiting root elongation. On Lemna minor all the compounds reduced the content of chlorophyll, with 1,7-dihyroxy-3-methylanthracene-9,10-dione being the most active. The new compounds, together with lentisone, proved to have antibiotic properties.

Ambrosia artemisiifolia L. is responsible for serious allergies induced on humans. Different approaches for its control were proposed during the COST Action FA1203 "Sustainable management of Ambrosia artemisiifolia in Europe" (SMARTER). Fungal secondary metabolites often show potential herbicidal activity. Three phytotoxins were purified from the fungal culture filtrates of Colletotrichum gloeosporioides, isolated from infected leaves of A. artemisiifolia. They were identified by spectroscopic and chemical methods as colletochlorin A, orcinol and tyrosol (1, 2 and 3). The absolute configuration 6'R to colletochlorin A was assigned for the first time applying the advanced Mosher's method. When assayed by leaf-puncture on A. artemisiifolia only 1 caused the appearance of large necrosis. The same symptoms were also induced by 1 on ambrosia plantlets associated with plant wilting. On Lemna minor, colletochlorin A caused a clear fronds browning, with a total reduction in chlorophyll content.

Safer and more environmentally friendly methods, including the use of natural substances, would be favorably considered for weed management, particularly in those habitats where the use of chemicals is restricted or banned. Ascochyta caulina, a proposed mycoherbicide for biocontrol of the weed Chenopodiumalbum, produces in liquid culture three main metabolites proposed as possible natural herbicides. Recently a research project,namedECO-VIA, initiated a series of studies aimed at developing the technologies to obtain a natural herbicide based on these bioactive metabolites. Particular attention was given to: maximizing toxin production; lowering the production costs; scaling up the production in fermentation systems; setting up a large scale purification method and identifying fast and inexpensive chemical methods to quantify toxins yields. The fungus proved to grow well and to produce up to 230 mgof toxins l_1 culture when grown for 5-10 days in shaken conditions, provided the initial inoculum was at least 105-106 conidia ml_1 of culture. Toxin production was improved by the addition of yeast extract to the medium. Given suitable inoculum and growth conditions, a stirred fermenter could be suitable for mass production of toxin.

Seed germination is a key phase of the parasitic plant life cycle that is stimulated by the secondary metabolites, mainly strigolactones (SLs), secreted by the host roots. Interventions during this stage would be particularly suitable for parasitic weed management practices, as blocking these chemical signals would prevent seed germination and thus parasite attack. Four fungal strains with different ecological functions were considered for their possible ability to metabolise SLs: Fusarium oxysporum and F. solani, biocontrol agents of Phelipanche ramosa; Trichoderma harzianum, a potential biopesticide; Botrytis cinerea, a phytopathogenic fungus. Four different SLs [the natural strigol, 5-deoxystrigol (5DS) and 4-deoxyorobanchol (4DO), and the synthetic analogue GR24] were added to fungal cultures, followed by determination of the SL content by liquid chromatography-tandem mass spectrometry.RESULTS: Differences were observed among microorganisms, treatments and SLs used. T. harzianum and F. oxysporum were the most capable of reducing the SL content; considering the whole set of fungi used, 5DS and 4DO proved to be the most degradable SLs.CONCLUSIONS: Beneficial microscopic fungi could differently be used for biocontrolling parasitic weeds, acting as a 'physiological'barrier, by preventing the germination of their seeds through the ability to biotransform the stimulatory signals.

The spread of invasive alien species threatens the conservation of natural ecosystems, being the second leading cause of biodiversity loss. Ailanthus altissima (Mill.) Swingle (tree of heaven) is one of the most damaging invasive alien plant species, and the most important one within the Alta Murgia National Park, the second largest park in Europe, containing a great wealth of biodiversity. The species is highly present throughout the park, both in anthropic places such as antique manors and sheepfolds, where farmers intentionally planted A. altissima trees for shade, and in natural habitats such as grasslands and rocky soils, fi elds, woods edges, dry stone walls and roadsides, where they spontaneously grew. The "LIFE Alta Murgia" project, started in 2013, was funded within the European LIFE+ Framework. Its main objective is to eradicate A. altissima from the Alta Murgia National Park. Many large areas have been restored by using an eco-friendly and sustainable strategy for tree of heaven control based on stem application techniques able to minimize herbicide use and reduce risks for health and environment. For broad high plant density patches, best results were obtained with one winter treatment with glyphosate followed by one summer completion treatment. Stem applications provided good control with low rates of herbicide and off ered many advantages: no drift, no off -target eff ects, selectivity, minimal need for equipment, the possibility of treatments in urban and natural areas. An offi cial protocol for tree of heaven management will be proposed.

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.