{"id":{"repo_id":"catania","oai_identifier":"oai:www.iris.unict.it:20.500.11769/588190"},"canonical_url":"https://search.dev.ndltd.org/etd/catania/oai:www.iris.unict.it:20.500.11769/588190","repository":{"repo_id":"catania","name":"Università degli Studi di Catania","base_url":"https://www.iris.unict.it/oai/request"},"display":{"title":"Molecular characterization of Rhizoctonia spp. isolates and sustainable approaches to control Rhizoctonia diseases in ornamental nursery","abstract":"Eighty-eight Rhizoctonia isolates were recovered from 30 ornamental species grown in nurseries in Sicily and their anastomosis group (AG) and subgroups were determined. Fifty-six isolates belong to binucleate Rhizoctonia BNR and 32 were multinucleate and identified as R. solani. The binucleate AG most frequently found in this survey was AG-R which has not been reported until now in Italy. Overall, disease data surveys correspond to the first reports of diseases caused by binucleate Rhizoctonia AG-A, AG-G, and R. solani AG-4 on Citrus volkameriana, Citrus sinensis × Poncirus trifoliata (Citrange), Trachycarpus fortunei, Arbutus unedo, Thevetia peruviana Bignonia sp., Carissa spp., Catharanthus roseus, Eugenia sp., Quercus ilex, Phyllirea angustifolia and Pittosporum tobira. The high frequency and disease incidence detected through surveys in ornamental nurseries located in Sicily clearly show as this fungus represents a serious threat for ornamental plant production. Based on these considerations, the research topics of this PhD thesis was focused to develop an effective integrated control program in controlling both Rhizoctonia infections in nursery and in suppressing and/or strongly reducing of resting structures (sclerotia) into soil. Therefore, following an in vitro screening of some BCAs effective against R. solani (AG-4 group) and Rhizoctonia BNR (AG-A, AG-G and AG-F groups), the consequent step was the efficacy evaluation of 6 commercial fungicides and 8 microbiological formulates under controlled environment (microcosms) for the control of Rhizoctonia crown and root rot. To this aim, a plant host-pathogen model was successfully set up by using Dodonea viscosa. Overall, these data clearly indicate that only tolclofos-methyl can be employed for chemical management of Rhizoctonia infections, although encouraging results were found for other fungicides. Regarding the valid measures to suppress pathogen inoculum, the efficacy of some fumigants was tested at label and sub label rates in 5 nursery experiments under different applicative conditions. Interesting data in suppressing Rhizoctonia survival were obtained even though in plots fumigated with low rates (up to 5-fold reduced) of dazomet and metham sodium, whereas viable Trichoderma colonies were almost always retrieved. However, TIF barrier has averagely enhanced retention fumigants capacity if compared to VIF, thus significantly increasing their efficacy in suppressing fungal inocula and viability of Trichoderma spp. Further experiments, performed to evaluate efficacy of a new fumigant (DMDS) in controlling Rhizoctonia inocula in cultivation substrates, clearly show as it could be supported as a valid alternative to standard fumigants, although it was actually registered against Meloydogine spp., Heterodera spp., Globodera spp and Pratylenchus spp. nematodes. Comprehensively, the present PhD thesis provides useful information about diffusion and control of Rhizoctonia disease on ornamental nurseries.","abstract_html":"Eighty-eight Rhizoctonia isolates were recovered from 30 ornamental species grown in nurseries in Sicily and their anastomosis group (AG) and subgroups were determined. Fifty-six isolates belong to binucleate Rhizoctonia BNR and 32 were multinucleate and identified as R. solani. The binucleate AG most frequently found in this survey was AG-R which has not been reported until now in Italy. Overall, disease data surveys correspond to the first reports of diseases caused by binucleate Rhizoctonia AG-A, AG-G, and R. solani AG-4 on Citrus volkameriana, Citrus sinensis × Poncirus trifoliata (Citrange), Trachycarpus fortunei, Arbutus unedo, Thevetia peruviana Bignonia sp., Carissa spp., Catharanthus roseus, Eugenia sp., Quercus ilex, Phyllirea angustifolia and Pittosporum tobira. The high frequency and disease incidence detected through surveys in ornamental nurseries located in Sicily clearly show as this fungus represents a serious threat for ornamental plant production. Based on these considerations, the research topics of this PhD thesis was focused to develop an effective integrated control program in controlling both Rhizoctonia infections in nursery and in suppressing and/or strongly reducing of resting structures (sclerotia) into soil. Therefore, following an in vitro screening of some BCAs effective against R. solani (AG-4 group) and Rhizoctonia BNR (AG-A, AG-G and AG-F groups), the consequent step was the efficacy evaluation of 6 commercial fungicides and 8 microbiological formulates under controlled environment (microcosms) for the control of Rhizoctonia crown and root rot. To this aim, a plant host-pathogen model was successfully set up by using Dodonea viscosa. Overall, these data clearly indicate that only tolclofos-methyl can be employed for chemical management of Rhizoctonia infections, although encouraging results were found for other fungicides. Regarding the valid measures to suppress pathogen inoculum, the efficacy of some fumigants was tested at label and sub label rates in 5 nursery experiments under different applicative conditions. Interesting data in suppressing Rhizoctonia survival were obtained even though in plots fumigated with low rates (up to 5-fold reduced) of dazomet and metham sodium, whereas viable Trichoderma colonies were almost always retrieved. However, TIF barrier has averagely enhanced retention fumigants capacity if compared to VIF, thus significantly increasing their efficacy in suppressing fungal inocula and viability of Trichoderma spp. Further experiments, performed to evaluate efficacy of a new fumigant (DMDS) in controlling Rhizoctonia inocula in cultivation substrates, clearly show as it could be supported as a valid alternative to standard fumigants, although it was actually registered against Meloydogine spp., Heterodera spp., Globodera spp and Pratylenchus spp. nematodes. Comprehensively, the present PhD thesis provides useful information about diffusion and control of Rhizoctonia disease on ornamental nurseries.","abstract_has_math":false,"creators":["FORMICA, PIETRO TINDARO"],"institution":"Università degli studi di Catania","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["POLIZZI, Giancarlo","RAPISARDA, Carmelo"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-12-10","date_published":"2014-12-10","updated_at":"2026-07-24T01:35:10Z","subjects":["Rhizoctonia spp., integrated control, biological control, metham sodium, dazomet, DMDS, molecular characterization, Rhizoctonia spp., ,controllo integrato, controllo biologico, metam sodio, dazomet, DMDS, caratterizzazione molecolare"],"languages":["eng"],"rights":["info:eu-repo/semantics/openAccess","license:PUBBLICO - Pubblico con Copyright","license uri:iris.PUB02"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/20.500.11769/588190","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Formica, PIETRO TINDARO","POLIZZI, Giancarlo","RAPISARDA, Carmelo"]},{"key":"dc:creator","label":"Author","values":["FORMICA, PIETRO TINDARO"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014-12-10"]},{"key":"dc:publisher","label":"Institution","values":["Università degli studi di Catania","place:Catania"]},{"key":"dc:type","label":"Dc Type","values":["info:eu-repo/semantics/doctoralThesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Rhizoctonia spp., integrated control, biological control, metham sodium, dazomet, DMDS, molecular characterization, Rhizoctonia spp., ,controllo integrato, controllo biologico, metam sodio, dazomet, DMDS, caratterizzazione molecolare"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["info:eu-repo/semantics/openAccess","license:PUBBLICO - Pubblico con Copyright","license uri:iris.PUB02"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/20.500.11769/588190"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Eighty-eight Rhizoctonia isolates were recovered from 30 ornamental species grown in nurseries in Sicily and their anastomosis group (AG) and subgroups were determined. Fifty-six isolates belong to binucleate Rhizoctonia BNR and 32 were multinucleate and identified as R. solani. The binucleate AG most frequently found in this survey was AG-R which has not been reported until now in Italy. Overall, disease data surveys correspond to the first reports of diseases caused by binucleate Rhizoctonia AG-A, AG-G, and R. solani AG-4 on Citrus volkameriana, Citrus sinensis × Poncirus trifoliata (Citrange), Trachycarpus fortunei, Arbutus unedo, Thevetia peruviana Bignonia sp., Carissa spp., Catharanthus roseus, Eugenia sp., Quercus ilex, Phyllirea angustifolia and Pittosporum tobira. The high frequency and disease incidence detected through surveys in ornamental nurseries located in Sicily clearly show as this fungus represents a serious threat for ornamental plant production. Based on these considerations, the research topics of this PhD thesis was focused to develop an effective integrated control program in controlling both Rhizoctonia infections in nursery and in suppressing and/or strongly reducing of resting structures (sclerotia) into soil. Therefore, following an in vitro screening of some BCAs effective against R. solani (AG-4 group) and Rhizoctonia BNR (AG-A, AG-G and AG-F groups), the consequent step was the efficacy evaluation of 6 commercial fungicides and 8 microbiological formulates under controlled environment (microcosms) for the control of Rhizoctonia crown and root rot. To this aim, a plant host-pathogen model was successfully set up by using Dodonea viscosa. Overall, these data clearly indicate that only tolclofos-methyl can be employed for chemical management of Rhizoctonia infections, although encouraging results were found for other fungicides. Regarding the valid measures to suppress pathogen inoculum, the efficacy of some fumigants was tested at label and sub label rates in 5 nursery experiments under different applicative conditions. Interesting data in suppressing Rhizoctonia survival were obtained even though in plots fumigated with low rates (up to 5-fold reduced) of dazomet and metham sodium, whereas viable Trichoderma colonies were almost always retrieved. However, TIF barrier has averagely enhanced retention fumigants capacity if compared to VIF, thus significantly increasing their efficacy in suppressing fungal inocula and viability of Trichoderma spp. Further experiments, performed to evaluate efficacy of a new fumigant (DMDS) in controlling Rhizoctonia inocula in cultivation substrates, clearly show as it could be supported as a valid alternative to standard fumigants, although it was actually registered against Meloydogine spp., Heterodera spp., Globodera spp and Pratylenchus spp. nematodes. Comprehensively, the present PhD thesis provides useful information about diffusion and control of Rhizoctonia disease on ornamental nurseries.","Da indagini di campo condotte in vivai situati in Sicilia, ottantotto isolati di Rhizoctonia spp. sono stati raccolti da 30 specie ornamentali e successivamente identificati secondo il gruppo di anastomosi appartenente (AG). Cinquantasei isolati sono stati identificati come Rhizoctonia binucleata (BNR), invece i rimanenti 32 presentavano celle multinucleate e sono stati identificati come R. solani. AG-R è stato il gruppo di anastomosi maggiormente rinvenuto, e segnalato per la prim volta in Italia. Nel complesso sono stati roportate nuove associazioni ospite-patogeno per i gruppi AG-A, AG-G e AG-4 su Citrus volkameriana, Citrus sinensis × Poncirus trifoliata (Citrange), Trachycarpus fortunei, Arbutus unedo, Thevetia peruviana, Bignonia sp., Carissa spp., Catharanthus roseus, Eugenia sp., Quercus ilex, Phyllirea angustifolia e Pittosporum tobira. La frequenza e l incidenza della malattia rilevata attraverso le mostrano chiaramente come questo patogeno rappresenta una grave minaccia per la produzione di piante ornamentali. Sulla base di queste considerazioni, i temi di ricerca di questa tesi di dottorato sono stati focalizzati sullo sviluppo di un programma di controllo integrato efficace nel nei confronti di Rhizoctonia spp. Pertanto, a seguito di uno screening in vitro dal quale è emersa l efficacia di alcuni BCA contro R. solani (AG-4 gruppi) e Rhizoctonia BNR (AG-A, AG-G e AG-F), l'efficacia di 6 fungicidi commerciali e 8 formulati biologici è stata valutata in ambiente controllato (microcosmo) per il contenimento di Rhizoctonia marciume del colletto e delle radici. La prova è stata effettuata utilizzando Dodonaea viscosa come pianta-modello. Nel complesso, questi dati indicano chiaramente che solo tolclofos-metile può essere impiegato per la gestione di infezioni causate da Rhizoctonia spp., anche se incoraggianti risultati sono stati trovati altri fungicidi. Per quanto riguarda misure atte a sopprimere l inoculo patogeno presente nel terreno, l'efficacia di alcuni fumiganti, saggiati alle dosi di etichetta e a dosi ridotte, è stata valutata. Queste prove hanno permesso di ottenere interessanti risultati in merito alla capacità di sopprimere la sopravvivenza di Rhizoctonia spp. e di recuperare comunque inoculo vitale di Trichoderma. Tuttavia, l applicazione di film totalmente impermeaili, capaci di elevata ritenzione dei fumiganti, hanno aumentato l efficacia rispetto ai trattamenti effetuati applicando film virtualmente impermeabili. Ulteriori esperimenti, eseguiti per valutare l'efficacia di un nuovo fumigante (DMDS) nel controllo Rhizoctonia spp. in substrati di coltivazione, mostrano chiaramente come DMDS potrebbe essere utilizzato come valida alternativa ai fumiganti standard, anche se al momento risulta registrato contro nematodi (Meloydogine spp., Heterodera spp. , Globodera spp e Pratylenchus spp.). In conclusione, la presente tesi di dottorato fornisce informazioni utili sulla diffusione e il controllo delle malattie causate da Rhizoctonia in vivai di piante ornamentali."]},{"key":"dc:title","label":"Title","values":["Molecular characterization of Rhizoctonia spp. isolates and sustainable approaches to control Rhizoctonia diseases in ornamental nursery"]}]}],"canonical_facts":{"dc:contributor":["Formica, PIETRO TINDARO","POLIZZI, Giancarlo","RAPISARDA, Carmelo"],"dc:creator":["FORMICA, PIETRO TINDARO"],"dc:date":["2014-12-10"],"dc:description":["Eighty-eight Rhizoctonia isolates were recovered from 30 ornamental species grown in nurseries in Sicily and their anastomosis group (AG) and subgroups were determined. Fifty-six isolates belong to binucleate Rhizoctonia BNR and 32 were multinucleate and identified as R. solani. The binucleate AG most frequently found in this survey was AG-R which has not been reported until now in Italy. Overall, disease data surveys correspond to the first reports of diseases caused by binucleate Rhizoctonia AG-A, AG-G, and R. solani AG-4 on Citrus volkameriana, Citrus sinensis × Poncirus trifoliata (Citrange), Trachycarpus fortunei, Arbutus unedo, Thevetia peruviana Bignonia sp., Carissa spp., Catharanthus roseus, Eugenia sp., Quercus ilex, Phyllirea angustifolia and Pittosporum tobira. The high frequency and disease incidence detected through surveys in ornamental nurseries located in Sicily clearly show as this fungus represents a serious threat for ornamental plant production. Based on these considerations, the research topics of this PhD thesis was focused to develop an effective integrated control program in controlling both Rhizoctonia infections in nursery and in suppressing and/or strongly reducing of resting structures (sclerotia) into soil. Therefore, following an in vitro screening of some BCAs effective against R. solani (AG-4 group) and Rhizoctonia BNR (AG-A, AG-G and AG-F groups), the consequent step was the efficacy evaluation of 6 commercial fungicides and 8 microbiological formulates under controlled environment (microcosms) for the control of Rhizoctonia crown and root rot. To this aim, a plant host-pathogen model was successfully set up by using Dodonea viscosa. Overall, these data clearly indicate that only tolclofos-methyl can be employed for chemical management of Rhizoctonia infections, although encouraging results were found for other fungicides. Regarding the valid measures to suppress pathogen inoculum, the efficacy of some fumigants was tested at label and sub label rates in 5 nursery experiments under different applicative conditions. Interesting data in suppressing Rhizoctonia survival were obtained even though in plots fumigated with low rates (up to 5-fold reduced) of dazomet and metham sodium, whereas viable Trichoderma colonies were almost always retrieved. However, TIF barrier has averagely enhanced retention fumigants capacity if compared to VIF, thus significantly increasing their efficacy in suppressing fungal inocula and viability of Trichoderma spp. Further experiments, performed to evaluate efficacy of a new fumigant (DMDS) in controlling Rhizoctonia inocula in cultivation substrates, clearly show as it could be supported as a valid alternative to standard fumigants, although it was actually registered against Meloydogine spp., Heterodera spp., Globodera spp and Pratylenchus spp. nematodes. Comprehensively, the present PhD thesis provides useful information about diffusion and control of Rhizoctonia disease on ornamental nurseries.","Da indagini di campo condotte in vivai situati in Sicilia, ottantotto isolati di Rhizoctonia spp. sono stati raccolti da 30 specie ornamentali e successivamente identificati secondo il gruppo di anastomosi appartenente (AG). Cinquantasei isolati sono stati identificati come Rhizoctonia binucleata (BNR), invece i rimanenti 32 presentavano celle multinucleate e sono stati identificati come R. solani. AG-R è stato il gruppo di anastomosi maggiormente rinvenuto, e segnalato per la prim volta in Italia. Nel complesso sono stati roportate nuove associazioni ospite-patogeno per i gruppi AG-A, AG-G e AG-4 su Citrus volkameriana, Citrus sinensis × Poncirus trifoliata (Citrange), Trachycarpus fortunei, Arbutus unedo, Thevetia peruviana, Bignonia sp., Carissa spp., Catharanthus roseus, Eugenia sp., Quercus ilex, Phyllirea angustifolia e Pittosporum tobira. La frequenza e l incidenza della malattia rilevata attraverso le mostrano chiaramente come questo patogeno rappresenta una grave minaccia per la produzione di piante ornamentali. Sulla base di queste considerazioni, i temi di ricerca di questa tesi di dottorato sono stati focalizzati sullo sviluppo di un programma di controllo integrato efficace nel nei confronti di Rhizoctonia spp. Pertanto, a seguito di uno screening in vitro dal quale è emersa l efficacia di alcuni BCA contro R. solani (AG-4 gruppi) e Rhizoctonia BNR (AG-A, AG-G e AG-F), l'efficacia di 6 fungicidi commerciali e 8 formulati biologici è stata valutata in ambiente controllato (microcosmo) per il contenimento di Rhizoctonia marciume del colletto e delle radici. La prova è stata effettuata utilizzando Dodonaea viscosa come pianta-modello. Nel complesso, questi dati indicano chiaramente che solo tolclofos-metile può essere impiegato per la gestione di infezioni causate da Rhizoctonia spp., anche se incoraggianti risultati sono stati trovati altri fungicidi. Per quanto riguarda misure atte a sopprimere l inoculo patogeno presente nel terreno, l'efficacia di alcuni fumiganti, saggiati alle dosi di etichetta e a dosi ridotte, è stata valutata. Queste prove hanno permesso di ottenere interessanti risultati in merito alla capacità di sopprimere la sopravvivenza di Rhizoctonia spp. e di recuperare comunque inoculo vitale di Trichoderma. Tuttavia, l applicazione di film totalmente impermeaili, capaci di elevata ritenzione dei fumiganti, hanno aumentato l efficacia rispetto ai trattamenti effetuati applicando film virtualmente impermeabili. Ulteriori esperimenti, eseguiti per valutare l'efficacia di un nuovo fumigante (DMDS) nel controllo Rhizoctonia spp. in substrati di coltivazione, mostrano chiaramente come DMDS potrebbe essere utilizzato come valida alternativa ai fumiganti standard, anche se al momento risulta registrato contro nematodi (Meloydogine spp., Heterodera spp. , Globodera spp e Pratylenchus spp.). In conclusione, la presente tesi di dottorato fornisce informazioni utili sulla diffusione e il controllo delle malattie causate da Rhizoctonia in vivai di piante ornamentali."],"dc:identifier":["https://hdl.handle.net/20.500.11769/588190"],"dc:language":["eng"],"dc:publisher":["Università degli studi di Catania","place:Catania"],"dc:rights":["info:eu-repo/semantics/openAccess","license:PUBBLICO - Pubblico con Copyright","license uri:iris.PUB02"],"dc:subject":["Rhizoctonia spp., integrated control, biological control, metham sodium, dazomet, DMDS, molecular characterization, Rhizoctonia spp., ,controllo integrato, controllo biologico, metam sodio, dazomet, DMDS, caratterizzazione molecolare"],"dc:title":["Molecular characterization of Rhizoctonia spp. isolates and sustainable approaches to control Rhizoctonia diseases in ornamental nursery"],"dc:type":["info:eu-repo/semantics/doctoralThesis"]},"updated_at":"2026-07-24T01:35:10Z"}