JOSEPH KUC´
Department of Plant Pathology, University of Kentucky, Lexington, Kentucky, 40546 USA

It is increasingly evident that the use of certain pesticides in plant production will become restricted at the same time that the productivity, profitability and competitiveness of agriculture must increase. Pesticides contribute to the problem of environmental deterioration which in turn has a marked influence on the economy, health, and the quality of life. At the same time, pesticides have been a major factor contributing to the increased crop yields and quality attained in modern agriculture. Aside from considerations for the environment, health and quality of life, the generation of new pesticides is becoming more difficult and expensive. Resistant strains of pathogens rapidly arise to many new systemic pesticides, and the difficulty of developing "environmentally-sound" pesticides has increased their cost and reduced the number that are available. Many recommended pesticides are being removed from the market and others can only be used on particular crops for restricted periods of time. Importers of agricultural products are setting strict limits for pesticide residues on food crops, and for some pesticides there is a zero tolerance. Consumers and consumer groups are also becoming increasingly concerned about pesticide use and residues on food products. Advances in biotechnology, including the development and introduction of transgenic plants, biocontrol, induced systemic resistance (plant immunization) and enhanced development and increased use of disease resistant plants utilizing new technologies developed by plant breeders, offer promise of providing alternative means of disease control that are effective and economical and which would reduce the dependence on pesticides. The newly developed biotechnology would, however, also have the effect of increasing the effectiveness of acceptable pesticides and increase their useful life in agriculture. Plant immunization regulates genes for defense compounds present even in susceptible plants, is as safe for the environment as disease resistant plants, since the same mechanisms for resistance are activated in immunized and resistant plants, and the effect is systemic and often lasts for the life of an annual plant (Kuc´, 1987, 1990; Dean and Kuc´, 1987a; Kuc´ and Tuzun, 1990; Tuzun and Kuc´, 1989; Madamanchi and Kuc´, 1991). Thus, existing high-yielding, high quality cultivars can be immunized. Immunization provides protection against a broad spectrum of pathogens including viruses, bacteria and fungi, and it does not require the introduction of "foreign" genes. Pesticides are not available for the economic control of plant disease caused by viruses and many bacteria. A single immunization of cucumber, muskmelon or watermelon, utilizing Colletotrichum lagenarium (Pass.) Ell. et Halsted, tobacco necrosis virus (TNV), immunization signal compounds or compounds which release such signals as the immunizing agents, systemically protects the plants against disease caused by 13 different pathogens (Kuc´, 1987, 1990; Dean and Kuc´, 1987a; Madamanchi and Kuc´, 1991). Immunization has been successful in both the laboratory and field (Kuc´, 1987, 1990; Kuc´ and Tuzun, 1990; Caruso and Kuc´, 1977; Tuzun et al., 1986). Disease resistance is multicomponent and layered, as would be expected for plants to survive the selection pressure of evolution. It includes pre-formed barriers and antimicrobial compounds, often in external tissues, and a response phase. The response phase includes as defense compounds: phytoalexins, chitinases, b -1,3-glucanases, proteases, peroxidases, phenoloxidases, hydroxyproline-rich glycoproteins, lignin, and callose. (Kuc´ 1987, 1990; Kuc´ and Tuzun, 1990; Dean and Kuc´, 1987a; Madamanchi and Kuc´, 1991; Tuzun and Kuc´, 1989). The expression of genes for the gene products contributing to disease resistance is regulated by compounds of plant and microbial origin (West et al., 1985; Sharp et al., 1984a,b,c; Madamanchi and Kuc´, 1991), and gene regulation — not the presence or absence of genes for resistance mechanisms — is likely to be the determinant of disease resistance in plants. Thus, all of the defense compounds noted above can be produced by resistant and susceptible plants, even by plants reported to lack genes for resistance to a pathogen. The speed, magnitude and timing of different elements of the response, and the activity of the gene products as influenced by the environment, determine resistance (Kuc´, 1987, 1990). The immunization of plants, including plants reported to lack genes for resistance, further supports the importance of gene expression (Kuc´, 1987, 1990). Immunization is possible by restricted inoculation with pathogens, attenuated pathogens, selected nonpathogens, and treatment with chemical substances which are signals produced by immunized plants or chemicals which release such signals (Kuc´, 1987, 1990).
The signal for immunization in cucurbits and tobacco is graft-transmissibile (Jenns and Kuc´, 1979; Tuzun and Kuc´, 1985). It is synthesized at the site of infection or treatment with the inducing agent (Dean and Kuc´, 1986) and is transported in the phloem (Guedes et al., 1980; Tuzun and Kuc´, 1985). Roots and leaves are immunized by treatment of leaves with an inducing agent (Gessler and Kuc´, 1982). The immunity signal conditions resistance even in tissue which has not emerged from the bud (Dalisay and Kuc´, 1989; Dean and Kuc´, 1986).
Three compounds isolated from immunized tobacco plants, b - ionone, 3-isobutyroyl-b-ionone and 3-n-butyroyl-b-ionone, protected tobacco in the laboratory and field against metalaxyl resistant and susceptible strains of the blue mold pathogen, Peronospora tabacina Adam (Salt et al., 1986, 1988; Kuc´ and Tuzun, 1990).
A group of compounds which release immunity signals may also find application for disease control. Oxalates and di and trisodium and di and tripotassium phosphates were recently reported to release immunity signals and systemically protect cucumber against anthracnose (Doubrava et al., 1988; Gottstein and Kuc´, 1989). The biological spectrum of effectiveness for oxalates and phosphates in cucumber includes as many diseases as reported for induction of resistance utilizing microorganisms (Mucharromah and Kuc´, unpublished).
Though immunization systemically increases the levels of some defense compounds such as chitinase, b -1,3-glucanases and peroxidases (Metraux and Boller 1986; Tuzun et al., 1989; Ye et al., 1989), its major effect is to sensitize plants to respond rapidly after infection (Hammerschmidt and Kuc´, 1982; Dean and Kuc´, 1987b; Kuc´ and Tuzun, 1990; Tuzun et al., 1989; Kuc´, 1984). Thus, energy and precursors are conserved and utilized when needed. Immunization has been demonstrated in at least 26 diverse plant-pathogen interactions including pear, apple, peach, coffee, tomato, potato, cucumber, barley, cotton, watermelon, muskmelon, wheat, green beans, soybean and sunflower (Kuc´, 1987; Strobel, unpublished data).To obtain the maximum advantage of each technology for disease control, it is important to integrate the technologies and to develop technology that can be integrated. A partially resistant plant would require less pesticide less frequently applied than would a susceptible plant. Immunization coupled with plants bred for resistance to some diseases would not only increase the level of resistance present but also increase the number of diseases to which the plant is resistant. Tobacco cv Tennessee 86 is resistant to etch and chlorotic vein mottling viruses but is highly susceptible to blue mold.
Immunization of this cultivar against blue mold rapidly produces plants which are resistant to the three diseases and resistance is transferred to regenerants via tissue culture (Nuckles and Kuc´, 1989; Tuzun and Kuc´, 1987, 1989). A transgenic plant with introduced resistance to a single disease might have a high level of resistance to some diseases bred into it and be immunized against others. To integrate technologies successfully requires that the product of integration will "fit" different agronomic demands. To do this will require not only the development of new technology, but will also require a new emphasis on and direction for field-oriented research. Hopefully, government, industry, academia and individual scientists will become increasingly aware and responsive to the need for funds to support not only the development of new technology but also funds to integrate and apply the technology for the practical control of plant disease in an emerging system of sustainable agriculture world-wide.
The objectives of this new integration of technologies would be to increase crop productivity, quality, and profitability and to reduce environmental and health hazards associated with pesticide use. It would be as unwise and unrealistic to advocate the elimination of pesticides from agriculture as it would be to eliminate the use of antibiotics from medicine. It is realistic, however, to advocate the restricted use of pesticides and their increased integration into other control practices. To an extent, this integration is already evident, e.g. the use of disease resistant plants and appropriate cultural practices with pesticides. At issue is the excessive use of pesticides and reluctance to explore the possibility of alternative means for disease control and their integration into practices where pesticides are a minor and not the sole or major control agent.
Key words: Plant immunization, Integrated control.
Parole chiave: Resistenza indotta, Lotta integrata.

Literature cited

Caruso F. and J. Kuc´, 1977. Field protection of cucumber, watermelon and muskmelon against Colletotrichum lagenarium by Colletotrichum lagenarium. Phytopathology, 67, 1285-1289.
Dalisay R. and J. Kuc´, 1989. Effect of removing the inducer leaf on the persistence of induced systemic resistance and enhanced peroxidase levels in cucumber. Phytopathology, 79, 1150.
Dean R. and J. Kuc´, 1986. Induced systemic protection in cucumber: The source of the "signal". Physological and Molecular Plant Pathology, 28, 227-233.
Dean R. and J. Kuc´, 1987a. Immunization against disease: The plant fights back. In: Fungal Infection of Plants (G. Pegg and P. Ayres, Eds) Cambridge University Press, Cambridge, 383-410.
Dean R. and J. Kuc´, 1987b. Rapid lignification in response to wounding and infection as a mechanism for induced systemic resistance in cucumber. Physiological and Molecular Plant Pathology, 31, 69-81.
Doubrava N., R. Dean and J. Kuc´, 1988. Induction of systemic resistance to anthracnose caused by Colletotrichum lagenarium in cucumber by oxalate and extracts from spinach and rhubarb leaves. Physiological and Molecular Plant Pathology, 33, 69-80.
Gessler C. and J. Kuc´, 1982. Induction of resistance to Fusarium wilt in cucumber by root and foliar pathogens. Phytopathology, 72, 1439-1441.
Gottstein H. and J. Kuc´, 1989. Induction of systemic resistance to anthracnose in cucumber by phosphates. Phytopathology, 79, 176-179.
Guedes M., S. Richmond and S. Kuc´, 1980. Induced systemic resistance in cucumber as influenced by the location of the inducer inoculation with Colletotrichum lagenarium and onset of flowering and fruiting. Physiological Plant Pathology, 17, 229-233.
Hammerschmidt R. and J. Kuc´, 1982. Lignification as a mechanism for induced systemic resistance in cucumber. Physiological Plant Pathology, 20, 61-71.
Jenns A. and J. Kuc´, 1979. Graft transmission of systemic resistance of cucumber to anthracnose induced by Colletotrichum lagenarium and tobacco necrosis virus. Phytopathology, 69, 753-756.
Kuc´ J., 1984. Phytoalexins and disease resistance mechanisms from a perspective of evolution and adaptation. In: Origin and Development of Adaptation. Pitman, London, 100-118.
Kuc´ J., 1987. Plant immunization and its applicability for disease control. In: Innovative Approaches to Plant Disease Control (I. Chet, Ed.) John Wiley, New York, 255-274.
Kuc´ J., 1990. Immunization for the control of plant disease. In: Biological Control of Soil-Borne Pathogens (D. Hornby, Ed.) CAB International Wallingford, UK, 355-373.
Kuc´ J. and S. Tuzun, 1990. Metabolic regulation of resistance genes in tobacco for the control of blue mold. In: Blue Mold Disease of Tobacco (C. Main, H. Spurr, Eds), Tobacco Literature Service, North Carolina State University, Raleigh, 35-46.
Madamanchi N.R. and J. Kuc´, 1991. Induced systemic resistance in plants. In: The Fungal Spore and Disease Initiation in Plants and Animals (G. Cole and H. Hoch, Eds) Plenum Press, New York, 347-362.
Metraux J. and T. Boller, 1986. Local and systemic induction of chitinase in cucumber plants in response to viral, bacterial and fungal infections. Physiological and Molecular Plant Pathology, 28, 161-169.
Nuckles E. and J. Kuc´, 1989. Immunization of tobacco cultivar Tn 86 against blue mold. Phytopathology, 79, 1152.
Salt S., S. Tuzun and J. Kuc´, 1986. Effects of b-ionone and abscisic acid on the growth of tobacco and resistance to blue mold. Physiological and Molecular Plant Pathology, 28, 287-297.
Salt S., M. Reuveni and J. Kuc´, 1988. Inhibition of Peronospora tabacina (blue mold of tobacco) and related plant pathogens in vitro and in vivo by esters of 3 (R)-hydroxy-b -ionone. 42nd Tobacco Chemists Conference Proceedings, Tobacco Chemists Soc., Lexington, Ky, USA, 22 pp.
Sharp J., P. Albersheim, P. Ossowski, A. Pilotti, P. Garegg and B. Lindberg, 1984a. Comparison of the structures and elicitor activities of synthetic and mycelial-wall derived hexa (B-D-glucopyranosyl) D-glucitol. Journal of Biological Chemistry, 259, 11341-11345.
Sharp J., M. McNeil and P. Albersheim, 1984b. The primary structures of one elicitor-active and seven elicitor-inactive hexa (B-D- glucopyranosyl) D- glucitols isolated from the mycelial walls of Phytophthora megasperma f. sp. glycinea. Journal of Biological Chemistry, 259, 11321-11336.
Sharp J., B. Valent and P. Albersheim, 1984c. Purification and partial characterization of a V-glucan fragment that elicits phytoalexin accumulation in soybean. Journal of Biological Chemistry, 159, 11312-11320.
Tuzun S. and J. Kuc´, 1985. Movement of a factor in tobacco infected with Peronospora tabacina which systemically protects against blue mold. Physiological Plant Pathology, 26, 321-330.
Tuzun S. and J. Kuc´, 1987. Persistence of induced systemic resistance to blue mold in tobacco plants derived via tissue culture. Phytopathology, 77, 1032-1035.
Tuzun S. and J. Kuc´, 1989. Induced systemic resistance in tobacco. In: Blue Mold of Tobacco (W. McKeen, Ed.) American Phytopathological Society Press, St. Paul, Mn, USA, 177-200.
Tuzun S., W. Nesmith, R. Ferriss and J. Kuc´, 1986. Effects of stem injections with Peronospora tabacina on growth of tobacco and protection against blue mold in the field. Phytopathology, 76, 938-941.
Tuzun S., M. Rao, U. Vogeli, C. Schardl and J. Kuc´, 1989. Induced systemic resistance to blue mold: early induction and accumulation of b -1,3-glucanases, chitinases and other (b-proteins) in immunized tobacco. Phytopathology, 79, 979-983.
West C., P. Moesta, D. Jin, A. Lois and K. Wickham, 1985. The role of pectic fragments of the plant cell wall in the responses to biological stress. In: Cellular and Molecular Biology of Plant Stress (J. Key and T. Kosuge, Ed.). A. Liss, New York, 335-349.
Ye X., S. Pan and J. Kuc´, 1989. Pathogenesis-related proteins and systemic resistance to blue mold and tobacco mosaic virus induced by tobacco mosaic virus, Peronospora tabacina and aspirin. Physiological and Molecular Plant Pathology, 35, 161-175.

ALBERTO MATTA
Dipartimento di Valorizzazione e Protezione delle Risorse agroforestali, Sezione di Patologia vegetale - Università di Torino, Via P. Giuria 15, I-10126 Torino

For acting in the most discontinuos and direct way the wound stress appears to be particularly suitable for the study of the role of cell injury per se in the induction of resistance to microbial pathogens. Such a role is emphasized by the production after wounding of antimicrobial chemical and physical barriers becoming increasingly efficient with time. Moreover, besides providing substitutive protective structures against wound parasites, the wound response might confer also to intact tissues higher resistance levels. It has been reported that wounding induces local resistance to Cladosporium cucumerinum in cucumber, Peronospora parasitica in radish, Fusarium lycopersici in tomato. Also cell injury caused by immersion in hot water or exposure to chloroform vapors of the roots of tomato plants is followed by an increased, transitory state of resistance to Fusarium and Verticillium wilt. The protection induced by abiotic stresses against Fusarium wilt of tomato is similar to the protection induced by treatments with avirulent fungi or fungal elicitors that injure part of the root tissues. Moreover both types of treatment are followed by similar changes with time of different enzyme activities and total phenols content. Cell injury is apparently involved in the resistance induced by microrganisms also against nonvascular infections. In some plants (cucumber, tobacco) microbial infections, but not wounds or other abiotic stresses, induce resistance systemically. The insucces to induce resistance to fungi systemically by wounding even in cucumber and tobacco is conflicting with the evidence that the plants react systemically to cell injury as such in many other ways (accumulation of phenols, increase of enzyme activities, accumulation of mRNA coded for PRs, synthesis of proteinase inhibitors that are probably factors of resistance against insects). The transmission of signals is clearly involved in the activation of systemic responses to cell injury. Further research aimed to the recognition of such signals appears to be necessary for a better understanding of the mechanisms of induction of active resistance in plants.
Key words: Induced resistance, Cell injury.

Il ruolo del danno cellulare nella resistenza indotta

Per le sue caratteristiche di immediatezza e discontinuità il trauma meccanico appare particolarmente adatto allo studio del ruolo del danno cellulare in sé nel fenomeno della resistenza indotta ai parassiti. Alcune delle principali risposte alla ferita o ad analoghe forme di danno cellulare consistono in:
1) precoce depolarizzazione di membrana seguita da rilascio di elettroliti, digestione enzimatica di lipidi con produzione di composti volatili fungitossici;
2) aumento di attività del ciclo respiratorio dei pentoso-fosfati e partecipazione nella respirazione di vie alternative cianuro-resistenti di trasporto elettronico sfocianti nella formazione di superossido;
3) ossidazione di preesistenti fenoli in chinoni fungitossici; sintesi de novo di fenoli e loro ossidazione o polimerizzazione a suberina e lignina;
4) sintesi di fitoalessine.
Gran parte delle risposte di cui sopra concorrono nei meccanismi di resistenza ai parassiti. Oltre a provvedere strutture protettive contro i parassiti da ferita, le risposte alle ferite possono determinare aumento di resistenza nei tessuti intatti circostanti. Le ferite inducono resistenza locale a Cladosporium cucumerinum in cetriolo, a Peronosporaparasitica in ravanello, a Fusarium lycopersici in pomodoro. Non solo, ma anche il danno cellulare prodotto da trattamenti con calore o composti tossici è seguito da un transitorio aumento di resistenza a F. lycopersici e Verticillium dahliae in pomodoro. La resistenza a F. lycopersici è similmente indotta dagli stress abiotici e dall’inoculazione con funghi avirulenti o con elicitori fungini capaci di lesionare i tessuti. Sia i trattamenti abiotici sia quelli biotici sono inoltre seguiti in pomodoro da cambiamenti, analoghi nel tempo, delle attività perossidasica, polifenolossidasica, chitinasica e b -1,3-glucanasica e della concentrazione fenolica. Danno cellulare è apparentemente richiesto anche nella induzione micro-biologica di resistenza locale verso infezione di patogeni non vascolari. Solo i microrganismi che causano necrosi ipersensibile o necrosi estese sono efficaci nell’indurre resistenza. In alcune piante (cetriolo, tabacco) le infezioni microbiche, ma non le ferite o altri stress abiotici, inducono resistenza sistemicamente. L’incapacità delle ferite di indurre resistenza sistemica in tabacco e cetriolo contrasta con l’evidenza che le piante reagiscono sistemicamente al danno cellulare come tale in molti altri modi: con aumento di svariate attività enzimatiche, accumulo di fenoli, accumulo di mRNA codificato per proteine di patogenesi, sintesi di inibitori proteici di proteineasi possibilmente funzionanti da fattori di resistenza agli insetti. La trasmissione di segnali ovviamente interviene nella trasmissione di risposte sistemiche al danno cellulare. È stato ipotizzato che i segnali possono essere di natura chimica (oligosaccaridi staccati dalle pareti cellulari, traumatina, etilene, ABA, ecc.) o elettrici ed elettrochimici. Lo sviluppo di ricerche rivolte all’individuazione del segnale trasmettitore di informazioni a tessuti distanti dalle cellule danneggiate sarà necessario per la comprensione dei meccanismi di induzione della resistenza attiva nelle piante.
Parole chiave: Resistenza indotta, Danno cellulare.

SALVATORE FRISULLO e VITTORIO ROSSI
Dipartimento di Biologia, Difesa e Biotecnologie Agro-Forestali, Università degli Studi della Basilicata, Via Nazario Sauro, 85, I-85100 Potenza

Con una indagine, svolta nel biennio 1988/89 in 5 località dell’Italia meridionale, è stata studiata la popolazione fungina associata alle radici ed ai culmi di frumento colpito dal "mal del piede", come pure le variazioni delle diverse specie fungine durante il periodo compreso fra l’accestimento e la maturazione delle spighe. Le specie isolate con maggiore frequenza sono state: Microdochium nivale, Fusarium culmorum, Drechslerasorokiniana, Fusarium avenaceum, Fusarium crookwellense, Fusarium graminearum e Rhizoctonia cerealis. La frequenza di isolamento di queste specie è variata in rapporto all’annata, alla località, allo stadio di sviluppo delle piante ed all’organo vegetale colpito.
Parole chiave: Frumento duro, Mal del piede, Marciume radicale, Fusarium culmorum, Microdochium nivale.

Changes of the fungal population associated with foot and root rot of durum wheat in southern Italy

A study on the fungal population associated with foot and root rot of durum wheat, from tillering to ripening, was carried out in five wheat-growing areas of southern Italy in 1988 and 1989. The species more frequently isolated from haulms and roots of the diseased plants were: Microdochium nivale, Fusarium culmorum, Drechslera sorokiniana, Fusarium avenaceum, Fusarium crookwellense, Fusarium graminearum and Rhizoctonia cerealis. Frequency of these species changed with regard to the year, the place, the developmental stage of plants and the part of plant from which they were isolated.
Key words: Durum wheat, Foot-rot, Root-rot, Fusariumculmorum, Microdochium nivale.

IPPOLITO CAMELE¹, MARIA NUZZACI¹, GIAN LUIGI RANA¹ e PANAIOTA E. KYRIAKOPOULOU^2
1Dipartimento di Biologia, Difesa e Biotecnologie Agro-Forestali, Università degli Studi della Basilicata, Via Nazario Sauro, 85, I-85100 Potenza
²Istituto Fitopatologico Benaki, Kiphissia, Atene, Grecia

Da piante di papavero, mostranti clorosi generalizzata o nanismo e maculatura giallastra ed infestanti rispettivamente alcuni carciofeti greci e pugliesi, sono stati isolati due virus fitopatogeni: il virus latente italiano del carciofo (AILV) e quello del mosaico della rapa (TuMV). I due virus sono stati identificati mediante immunomicroscopia elettronica seguita da decorazione.
Parole chiave: Carciofo, Papavero, Virus latente italiano del carciofo, Virus del mosaico della rapa.

Papaver rhoeas as a host for two phytopathogenic viruses

Two plant viruses, artichoke Italian latent virus (AILV) and turnip mosaic virus (TuMV) were isolated from wild plants of Papaver rhoeas L. growing in artichoke fields in Greece and southern Italy and showing chlorosis or yellow mottle accompained by leaf and stem deformation, respectively. The viruses were identified by immuno-sorbent electron microscopy followed by decoration.
Key words: Artichoke, Poppy, Artichoke Italian latent virus, Turnip mosaic virus.

Organizzato da/Organized by:
DI.VA.P.R.A. - Patologia Vegetale, Università Di Torino, Italy
 
 

The International Trichoderma and Gliocladium Workshops are organized to promote exchange of ideas and information among researchers working on various aspects of these two important fungi. The first Workshop was held in 1984 at the Beltsville Agricultural Research Center (MD, USA). At that time the group decided to meet alternatively in the eastern and western hemispheres. The pace of research in many areas, such as taxonomy, genetic manipulation, enzyme production, ability to act as biological control agents, has quickened so much that the group, after the second meeting at Salford (UK), decided to meet every other year, in order to promote better discussion and exchange of information among researchers. During the last few years both plant pathologists and commercial companies have shown great interest in the potential of Trichoderma and Gliocladium as biocontrol agents and molecular biology approaches have been successfully used to improve strains and to better understand their mode of action. The University of Torino is very pleased to host this fourth meeting at Belgirate (Northern Italy). The large participation of young researchers, coming from all over the world, is particularly welcome. We hope that the discussion at this meeting will be fruitful and helpful to further progress of research in the different areas.We gratefully acknowledge all financial contributions received from the Ministry of Agriculture and Forestry, the University of Torino and the Piedmont Region Government.

M. Lodovica Gullino
 
 

Gli incontri internazionali su "Trichoderma e Gliocladium" sono organizzati per favorire lo scambio di informazioni e la discussione tra quanti conducono ricerche su questi due importanti funghi. Il primo Workshop venne organizzato presso l’Agricultural Research Center di Beltsville (Maryland, USA) nel 1984: in tale occasione, i ricercatori operanti in questo settore decisero di incontrarsi, a intervalli regolari, alternativamente in America e in Europa. Il ritmo assunto dalla ricerca su questi due funghi in diversi settori (ad esempio tassonomia, manipolazione genetica, produzione di enzimi, lotta biologica) ha spinto il gruppo, durante il secondo Workshop svoltosi a Salford (Gran Bretagna), a incontrarsi ogni due anni, per facilitare al massimo la discussione e lo scambio di idee. In questi ultimi anni si è osservato un crescente interesse, da parte dei ricercatori e dell’ industria agrochimica, verso il potenziale impiego di Trichoderma e Gliocladium come mezzi biologici di lotta: il ricorso a tecniche di biologia molecolare sta consentendo da un lato di migliorare le prestazioni dei ceppi antagonisti e dall’altro di chiarire i loro meccanismi di azione.
L’Università di Torino è onorata di ospitare il quarto incontro a Belgirate (Novara). E’ particolarmente apprezzata la partecipazione di giovani ricercatori, provenienti da aree geografiche diverse. Ci auguriamo che la discussione e lo scambio di idee siano particolarmente fruttuosi e che possano favorire l’avanzamento della ricerca nei diversi settori. Si ringrazia vivamente il Ministero dell’Agricoltura e delle Foreste, l’Università degli studi di Torino e la Regione Piemonte per avere generosamente contribuito alla organizzazione di questo convegno.

M. Lodovica Gullino
 
 

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