Utjecaj mikrobioma kvržica na simbioznu fiksaciju dušika i održivi uzgoj mahunarki

master's thesis

• Title (english): Impact of the nodule microbiome on symbiotic nitrogen fixation and sustainable legume production
• Author: Sara Matraković
• Mentor: Sanja Sikora (mentor)
• Committee member: Sanja Sikora (predsjednik povjerenstva)
• Committee member: Nataša Hulak (član povjerenstva)
• Committee member: Mihaela Blažinkov (član povjerenstva)
• Granter: University of Zagreb; Faculty of Agriculture; (Microbiology); Zagreb
• Defense date and country: 2021-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Agronomy

Abstract

Suvremena konvencionalna poljoprivreda zbog intenzivnog načina proizvodnje hrane, može
imati negativan utjecaj na okoliš i zdravlje svih bića. Umjesto primjene mineralnih gnojiva i
kemijskih sredstava za zaštitu bilja, traže se ekološke alternative, a jedna od njih je i uporaba
mikroorganizama u poljoprivredi. Mikroorganizmi koji se nalaze u rizosferi biljke i na ili u njoj
samoj čine njen mikrobiom, a članovi su razni rodovi bakterija, gljiva i arheja. Porodica
mahunarki (lat. Fabaceae) uključuje neke od najvažnijih poljoprivrednih usjeva iza žitarica i
predstavlja dobru podlogu za istraživanje mikrobioma zbog simbiozne asocijacije s kvržičnim
bakterijama – rizobijama, prilikom koje dolazi do nastanka kvržica na korijenu u kojima se
odvija proces simbiozne fiksacije dušika. Novijim istraživanjima dokazalo se kako se uz dobro
poznate i najčešće rodove rizobija poput Rhizobium, Bradyrhizobium i Mesorhizobium, u
kvržicama nalaze i ostali rodovi bakterijskih endofita. Rodovi bakterija poput Pseudomonas,
Bacillus i aktinobakterija Streptomyces, djeluju kao promotori biljnog rasta (PGPB, eng. Plant
growth promoting bacteria) proizvodnjom biljnih hormona i siderofora, antimikrobnih i
antigljivičnih supstanci, te indirektno svojom prisutnošću jačaju otpornost biljke na stresore.
Uloge svih članova mikrobioma još nisu u dovoljnoj mjeri proučene, ali predstavljaju
potencijal za daljnja istraživanja i primjenu. Ispitivanje učinkovitosti zajednice endofitskih
bakterija u kvržicama, rizobija i ne-rizobija, predstavlja dobar put prema ekološkoj i održivoj
poljoprivrednoj proizvodnji mahunarki.

Abstract (english)

Modern conventional agriculture, due to the intensive way of food production, can have a
negative impact on the environment and the health of all beings. Instead of applying mineral
fertilizers and chemical plant protection products, ecological alternatives are being sought,
and one of them is the use ofmicroorganisms in agriculture which can improve plant growth
and development. Microorganisms found in the plant rhizosphere and on or in the plant
itself make up its microbiome, and the members are various genera of bacteria, fungi, and
archaea. Legume family (lat. Fabaceae) includes some of the most important agricultural
crops after cereals, and represents a good basis for microbiome research due to the
symbiotic association with nodule bacteria - rhizobia, creating nodules at the root of
legumes where fixation of atmospheric nitrogen takes place. Recent research has shown that
in addition to the well - known and most common genera of rhizobia such as Rhizobium,
Bradyrhizobium and Mesorhizobium, nodules also contain other genera of bacteria. Bacteria
genera such as Pseudomonas, Bacillus and actinobacteria Streptomyces act as plant growth
promoters (PGPB) with production of plant hormones and siderophores, antimicrobial and
antifungal substances, while also indirectly with their presence, strengthening the plant's
resistance to stressors. The roles of all members of the microbiome haven't yet been
sufficiently studied, but represent the potential for further research and application.
Examining the effectiveness of the community of endophytic bacteria in nodules, rhizobia
and non-rhizobia, represents a good path towards organic and sustainable agricultural
production of legumes.

• Keywords: mikrobiom; mahunarke; simbiozna fiksacija dušika; rizobije
• Keywords (english): microbiome; legumes; symbiotic nitrogen fixation; rhizobia
• Language: croatian
• URN:NBN: urn:nbn:hr:204:937423
• Study programme: Title: Agroecology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/ magistra inženjer/inženjerka agroekologije (magistar/ magistra inženjer/inženjerka agroekologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to authenticated users
• Created on: 2021-12-06 07:47:01