Search results for " biocontrol"
showing 10 items of 13 documents
Wild and cultivated mushrooms as a model of sustainable development
2013
The natural resources are currently overexploited and since 1992 the Conference of Rio de Janeiro has focused on sustainable development to safeguard our planet for future generations. The Fungi kingdom includes producers of goods and services for ecosystems and organisms widely used in the food industry. Besides, macrofungi are recognized as nontimber forest products and could be utilized as agents of environmental management through weed biocontrol and environmental improvement. Moreover, the cultivation of fungi, in particular truffles, can provide an important income in agroecosystems, especially in marginal areas, along with the development of new technologies to produce novel products…
Assessment of the Antimicrobial Activity and the Entomocidal Potential of Bacillus thuringiensis Isolates from Algeria.
2017
This work represents the first initiative to analyze the distribution of B. thuringiensis in Algeria and to evaluate the biological potential of the isolates. A total of 157 isolates were recovered, with at least one isolate in 94.4% of the samples. The highest Bt index was found in samples from rhizospheric soil (0.48) and from the Mediterranean area (0.44). Most isolates showed antifungal activity (98.5%), in contrast to the few that had antibacterial activity (29.9%). A high genetic diversity was made evident by the finding of many different crystal shapes and various combinations of shapes within a single isolate (in 58.4% of the isolates). Also, over 50% of the isolates harbored cry1, …
Use of autochthonous yeasts and bacteria in order to control Brettanomyces bruxellensis in wine
2017
Biocontrol strategies for the limitation of undesired microbial developments in foods and beverages represent a keystone toward the goal of more sustainable food systems. Brettanomyces bruxellensis is a wine spoilage microorganism that produces several compounds that are detrimental for the organoleptic quality of the wine, including some classes of volatile phenols. To control the proliferation of this yeast, sulfur dioxide is commonly employed, but the efficiency of this compound depends on the B. bruxellensis strain; and it is subject to wine composition and may induce the entrance in a viable, but nonculturable state of yeasts. Moreover, it can also elicit allergic reactions in humans. …
CARATTERIZZAZIONE METAGENOMICA di MICRORGANISMI E ORGANISMI DEL TERRENO PER UN LORO UTILIZZO COME AGENTI di LOTTA BIOLOGICA CONTRO NEMATODI FITOPARAS…
2014
La microflora della rizosfera riveste un ruolo fondamentale sia nella difesa che nello sviluppo e crescita delle piante. Molti studi hanno dimostrato inoltre che i nematodi sono in grado d’influenzarne la composizione. I batteri a loro volta producono una varietà di composti (antibiotici, nutrienti, esoenzimi e altre molecole segnale), in grado d’indurre ulteriori cambiamenti. L’obiettivo di questo lavoro è stato quello di studiare i cambiamenti nella biodiversità della microflora batterica di un terreno proveniente da un’azienda biologica, conseguenti all'introduzione sperimentale di larve di Meloidogyne incognita e al trattamento con un nematocida (fenamifos). Seguendo un approccio metage…
Midgut microbiota and host immunocompetence underlie Bacillus thuringiensis killing mechanism
2016
Bacillus thuringiensis is a widely used bacterial entomopathogen producing insecticidal toxins, some of which are expressed in insect-resistant transgenic crops. Surprisingly, the killing mechanism of B. thuringiensis remains controversial. In particular, the importance of the septicemia induced by the host midgut microbiota is still debated as a result of the lack of experimental evidence obtained without drastic manipulation of the midgut and its content. Here this key issue is addressed by RNAi-mediated silencing of an immune gene in a lepidopteran host Spodoptera littoralis, leaving the midgut microbiota unaltered. The resulting cellular immunosuppression was characterized by a reduced …
Antifungal peptides produced by Bacillus amyloliquefaciens AG1 active against grapevine fungal pathogens
2012
Abstract Antifungal metabolites produced by Bacillus amyloliquefaciens AG1, previously isolated from wood of grapevine with “esca syndrome”, were studied. The crude protein extract (CPE) obtained from culture supernatant fluid by precipitation with ammonium sulfate was assayed against many grapevine fungal pathogens. B. amyloliquefaciens strain AG1 showed a broad spectrum of antifungal activity, inhibiting mycelial growth in vitro of all tested fungal microorganisms. The metabolites contained in CPE were heat stable and remained active over a wide pH range (2–10). Their activity was not affected by proteolytic or glycolytic enzymes. Tricine- SDS-polyacrylamide gel electrophoresis revealed a…
Prove preliminari di lotta biologica con Beauveria bassiana e Metarhizium anisopliae nei confronti del Punteruolo rosso
2009
Nell’intento di individuare limitatori biologici naturali di R. ferrugineus è stata valutata la potenziale attività antagonistica di due microrganismi fungini, appartenenti a specie dalle comprovate attitudini entomopatogene nei confronti di differenti stadi asintomatici dell’insetto (larve ed adulti). Più nel dettaglio, è stata saggiata l’efficacia di un ceppo di Beauveria bassiana, isolato da una larva con evidente efflorescenza fungina rinvenuta nel comune di Palermo e di un formulato commerciale a base di Metarhizium anisopliae e di B. bassiana. I saggi di inoculazione artificiale “in vitro” con queste note specie entomopatogene hanno indotto, in alcuni casi, la morte del 90% circa degl…
Review of factors influencing the success or failure of biocontrol: technical, industrial and socio-economic perspectives
2010
Communication orale au 11. IOBC-WPRS Meeting of the working group "Biological control of fungal and bacterial plant pathogens". Climate change: challenge or threat to biocontrol?, 2010/06/07-11 ; Graz (AUT).; International audience; Although their role in plant health management is still quite modest, ever increasing expectations are placed on biocontrol agents for the complementation or replacement of pesticide use. Despite decades of research and more than 12,000 scientific papers on biological control of plant diseases, little more than 14 microbe-based commercial products are presently registered for use against diseases in the European Union. Through a review of published scientific li…
Antagonism and Antimicrobial Capacity of Epiphytic and Endophytic Bacteria against the Phytopathogen Xylella fastidiosa
2022
Olive quick decline syndrome (OQDS), which is caused by Xylella fastidiosa, poses a severe threat to the agriculture of Mediterranean countries and causes severe damage to the olive trees in Italy. Since no effective control measures are currently available, the objective of this study was the screening of antagonistic bacteria that are potentially deployable as biocontrol agents against X. fastidiosa. Therefore, two approaches were used, i.e., the evaluation of the antagonistic activity of (i) endophytic bacteria isolated from two different cultivars of olive trees (Leccino and Ogliarola salentina) and (ii) epiphytic bacteria isolated from the phyllospheres of different host plant species …
Efficacy of microbial consortia and natural compounds as seed treatment for tomato pathogen management
2022
In this study the efficacy of experimental treatments based on microbial consortia (MC) (beneficial rhizobacteria and fungi, actinomycetes, arbuscular mycorrhizal fungi) and natural compounds (NCs) (chitosan and glucosinolates) as seed treatments for tomato bacterial and fungal pathogens management (Xanthomonas euvesicatoria pv. perforans, Xep; Pseudomonas syringae pv. tomato, Psto; Fusarium oxysporum f. sp. radicis-lycopersici, FORL) was evaluated. Independent trials were performed by using organic tomato seeds ‘San Marzano nano’. Treatments were performed by soaking seeds either in aqueous MC suspensions or NC dilutions. The direct effect on the seed inoculum was performed on seeds inocul…