The application of microorganisms in agriculture represents an innovative approach aimed at optimizing crop growth by reducing production costs and environmental impact. Technological progress and increase biotechnological knowledge, in relation to the ever-emerging demand to identify sustainable solutions for the environment, have made it possible to isolate new bacterial species present in the rhizosphere, potentially useful as biostimulants and marketed as such. Within this context is BlueN, a microbial biostimulant made up of the endophytic bacterium Methylobacterium symbioticum SB23. This bacterium proliferates in the presence of methanol (a plant waste product) and fixes atmospheric nitrogen (N2) to convert it into the forms assimilable by the plant, i.e., molecules with a high biological value which are essential for protein and enzyme biosynthesis, thus establishing a symbiotic relationship with it. The present thesis work was carried out at Innova-Tech s.r.l. with the aim of analyzing the consequential effects by applying BlueN on two main rice varieties: Aivori and Sinfonia. Furthermore, the potential interactions of BlueN were evaluated when associated with a second commercial product, Ympact, containing an organic-mineral complex conjugated with stimulating action micronutrients. The laboratory analyses carried out at Corteva Agriscience headquarters in Gadesco Pieve Delmona (CR) made it possible to evaluate the contribution of organic Nitrogen and the main macro- (Phosphorus and Potassium) and micronutrients (Sulfur, Silicon, Magnesium, Zinc, Iron, Molybdenum, etc.), which are essential for growth and maturation of the two rice varieties. Furthermore, a microbiological survey was conducted to verify the presence of the microorganism Methylobacterium symbioticum on the treated rice plants and to analyze the diffusive capacity of the bacterium with respect to the phenological stages of the crop. In general, the data obtained shown the efficacy of the catalytic activity of M. symbioticum, while the combined use of BlueN and Ympact revealed a synergistic action of the two compounds. In particular, the increase in Nitrogen content has been observed compared to the corresponding untreated witnesses was observed, with an increase of up to 107.4% for plant samples and up to 13.1% for paddy rice samples. The positive trend was also observed for the macro- and micronutrients essential for the crop: Phosphorus, Sulfur, Silicon, Magnesium and Calcium, involved in the uptake processes and in the development phases of the plant organism, when compared with the main polluting elements (Arsenic and Lead). The other chemical elements relevant from a statistical point of view were found to be Copper, Zinc and Manganese, constituents of the organic-mineral mixture of Ympact. It was also interesting to observe the variation in ppm values of Iron and Molybdenum, which, in addition to participating in the normal enzymatic processes of the plant, constitute the metal cluster of the bacterial enzyme Nitrogenase, essential for the fixation of atmospheric nitrogen (N2) to ammonia (NH3) and ammonium ion (NH4+). For the overall assessment of the qualitative and quantitative effects observed, it is necessary to consider the precarious agricultural year that took place in the 2021/2022 season, which, due to the severe drought, drastically compromised the growth and production of several agricultural crops. Nonetheless, the analyses carried out for the realization of this thesis have enabled a more complete picture of the structural and productive support provided by BlueN and Ympact applied to the rice crop system under study.
L’applicazione in ambito agrario di microrganismi rappresenta un approccio innovativo volto ad ottimizzare la crescita colturale riducendo i costi di produzione e l’impatto ambientale. Il progresso tecnologico e l’incremento delle conoscenze biotecnologiche, in relazione alla richiesta sempre più emergente di individuare soluzioni sostenibili per l’ambiente, hanno permesso di isolare nuove specie batteriche presenti nella rizosfera potenzialmente utili quali biostimolanti e come tali messi in commercio. All’interno di questo panorama si colloca BlueN, un biostimolante microbico costituito dal batterio endofitico Methylobacterium symbioticum SB23. Tale batterio prolifera in presenza di metanolo (prodotto di scarto dei vegetali) e fissa l’azoto atmosferico (N2) per convertirlo nelle forme assimilabili dalla pianta, ossia molecole ad alto valore biologico fondamentali per la biosintesi proteica ed enzimatica, instaurando così un rapporto di simbiosi con essa. Il presente lavoro di tesi è stato svolto presso l’azienda Innova-Tech s.r.l. con lo scopo di analizzare gli effetti conseguenti all’applicazione di BlueN su due principali varietà di riso: Aivori e Sinfonia. Inoltre, sono state valutate le potenziali interazioni di BlueN quando associato ad un secondo prodotto commerciale, Ympact, contenente un complesso organico-minerale coniugato con micronutrienti ad azione stimolante. Le analisi di laboratorio svolte presso la sede di Corteva Agriscience di Gadesco Pieve Delmona (CR) hanno permesso di valutare sulle due varietà di riso l’apporto di Azoto organico e dei principali macro- (Fosforo e Potassio) e micronutrienti (Zolfo, Silicio, Magnesio, Zinco, Ferro, Molibdeno etc.), essenziali per l’accrescimento e per la maturazione. Inoltre, è stata condotta un’indagine microbiologica che ha consentito di verificare la presenza del microrganismo Methylobacterium symbioticum sulle piante di riso trattate e di analizzare la capacità diffusiva del batterio rispetto alle fasi fenologiche della coltura. In generale, i dati ottenuti hanno evidenziato l’efficacia dell’attività catalitica di M. symbioticum, mentre l’uso combinato di BlueN e Ympact ha messo in evidenza un’azione sinergica dei due composti. In particolare, è stato osservato l’aumento del contenuto di Azoto rispetto ai corrispondenti testimoni non trattati, con un incremento fino al 107,4% per i campioni di pianta e fino al 13,1% per i campioni di risone. La tendenza positiva è stata osservata anche per i macro- e micronutrienti essenziali per la coltura: Fosforo, Zolfo, Silicio, Magnesio e Calcio, coinvolti nei processi di assorbimento e nelle fasi di sviluppo dell’organismo vegetale, rispetto ai principali elementi inquinanti (Arsenico e Piombo). Gli altri risultati statisticamente rilevanti riguardano il Rame, lo Zinco ed il Manganese, costituenti della miscela organico-minerale di Ympact. È stato inoltre interessante osservare la variazione dei valori in ppm di Ferro e Molibdeno che, oltre a partecipare ai normali processi enzimatici della pianta, costituiscono il cluster metallico dell’enzima batterico Nitrogenasi, indispensabile per la fissazione dell’azoto atmosferico (N2) ad ammoniaca (NH3) e ione ammonio (NH4+). Ai fini della valutazione complessiva degli effetti quali-quantitativi osservati è necessario tenere in considerazione la precaria annata agricola intercorsa nella stagione 2021/2022 che, a causa della forte siccità, ha compromesso drasticamente la crescita e la produzione di svariate colture agricole. Nonostante ciò, le analisi eseguite per la realizzazione del presente elaborato hanno consentito di delineare un quadro più completo del sostegno strutturale e produttivo fornito da BlueN e Ympact applicati al sistema colturale risicolo oggetto di studio.
Methylobacterium symbioticum in risaia: analisi degli effetti qualitativi e quantitativi conseguenti alla sua applicazione in agricoltura
SINCERO, FRANCESCA
2022/2023
Abstract
The application of microorganisms in agriculture represents an innovative approach aimed at optimizing crop growth by reducing production costs and environmental impact. Technological progress and increase biotechnological knowledge, in relation to the ever-emerging demand to identify sustainable solutions for the environment, have made it possible to isolate new bacterial species present in the rhizosphere, potentially useful as biostimulants and marketed as such. Within this context is BlueN, a microbial biostimulant made up of the endophytic bacterium Methylobacterium symbioticum SB23. This bacterium proliferates in the presence of methanol (a plant waste product) and fixes atmospheric nitrogen (N2) to convert it into the forms assimilable by the plant, i.e., molecules with a high biological value which are essential for protein and enzyme biosynthesis, thus establishing a symbiotic relationship with it. The present thesis work was carried out at Innova-Tech s.r.l. with the aim of analyzing the consequential effects by applying BlueN on two main rice varieties: Aivori and Sinfonia. Furthermore, the potential interactions of BlueN were evaluated when associated with a second commercial product, Ympact, containing an organic-mineral complex conjugated with stimulating action micronutrients. The laboratory analyses carried out at Corteva Agriscience headquarters in Gadesco Pieve Delmona (CR) made it possible to evaluate the contribution of organic Nitrogen and the main macro- (Phosphorus and Potassium) and micronutrients (Sulfur, Silicon, Magnesium, Zinc, Iron, Molybdenum, etc.), which are essential for growth and maturation of the two rice varieties. Furthermore, a microbiological survey was conducted to verify the presence of the microorganism Methylobacterium symbioticum on the treated rice plants and to analyze the diffusive capacity of the bacterium with respect to the phenological stages of the crop. In general, the data obtained shown the efficacy of the catalytic activity of M. symbioticum, while the combined use of BlueN and Ympact revealed a synergistic action of the two compounds. In particular, the increase in Nitrogen content has been observed compared to the corresponding untreated witnesses was observed, with an increase of up to 107.4% for plant samples and up to 13.1% for paddy rice samples. The positive trend was also observed for the macro- and micronutrients essential for the crop: Phosphorus, Sulfur, Silicon, Magnesium and Calcium, involved in the uptake processes and in the development phases of the plant organism, when compared with the main polluting elements (Arsenic and Lead). The other chemical elements relevant from a statistical point of view were found to be Copper, Zinc and Manganese, constituents of the organic-mineral mixture of Ympact. It was also interesting to observe the variation in ppm values of Iron and Molybdenum, which, in addition to participating in the normal enzymatic processes of the plant, constitute the metal cluster of the bacterial enzyme Nitrogenase, essential for the fixation of atmospheric nitrogen (N2) to ammonia (NH3) and ammonium ion (NH4+). For the overall assessment of the qualitative and quantitative effects observed, it is necessary to consider the precarious agricultural year that took place in the 2021/2022 season, which, due to the severe drought, drastically compromised the growth and production of several agricultural crops. Nonetheless, the analyses carried out for the realization of this thesis have enabled a more complete picture of the structural and productive support provided by BlueN and Ympact applied to the rice crop system under study.È consentito all'utente scaricare e condividere i documenti disponibili a testo pieno in UNITESI UNIPV nel rispetto della licenza Creative Commons del tipo CC BY NC ND.
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https://hdl.handle.net/20.500.14239/16317