Naslov
Nodule microbiome: biodiversity and function of bacteria associated with chickpea nodules

Autori
Sikora, Sanja ; Rajnović, Ivana ; Kajić, Sanja ; Toth, Nina ; Goreta Ban, Smiljana ; Maričić, Branka ; Vasilj, Višnja

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Skup
7th Croatian Congress of Microbiology

Mjesto i datum
Sveti Martin na Muri, Hrvatska, 24.05.2022. - 27.05.2022

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
PGPR, nitrogen fixation, rhizobia, biodiversity, indigenous strains

Sažetak
The use of beneficial microorganisms is of great importance in modern agriculture development. The concept of biodiversity based agriculture (BBA) relies on sustainable diversification of all biological components to increase ecosystem service provision and reduce the external input in farming systems. In the focus of many researchers as well as many biotech companies is a very diverse group of soil bacteria called plant growth-promoting rhizobacteria (PGPR) because of its beneficial effect on the overall well-being of the plant. PGPR include various nitrogen-fixing bacteria that enable the conversion of molecular nitrogen into available form for plant nutrition. Selection of high-quality rhizobial strains is a powerful tool for improving beneficial effect of legume inoculation particularly under adverse environmental conditions. Although for many years rhizobia were thought to be the only nitrogen-fixing inhabitants of legume nodules, recent studies revealed the existence of very diverse bacterial community within the nodules. The aim of the present study was to reveal the biodiversity within chickpea/lentil nodules, primarily to detect rhizobial strains with improved characteristics. Soil samples were taken from different locations along the coastal part of Croatia as well as from the southern part of Herzegovina. Isolation of indigenous chickpea and lentil rhizobia was performed by trap-host method. Around 185 isolates were obtained that have to be verified, identified and characterized. Most isolates showed unusual phenotypic properties for rhizobia indicating wide diversity within nodule microbiome. Several authentication tests of selected isolates were performed under controlled conditions in order to test their nodulation ability. In two experiments, 37 chickpea rhizobial strains were tested and nodulation was determined on plants inoculated with 19 isolates. The results of rrs gene sequencing revealed considerable diversity within nodule microbiome which includes Alpha-, Beta-, Gamma-proteobacteria and actinobacteria as well. Isolates that caused nodulation on chickpea roots, were clustered in very different groups of alfaproteobacteria. PGPR traits of selected isolates were tested and the results revealed that some of them have a beneficial effect on plant growth. Further analyzes are needed in order to determine the presence of nod and nif genes in isolates and to perform their more precise molecular and symbiotic characterization

Izvorni jezik
Engleski

Znanstvena područja
Poljoprivreda (agronomija)

POVEZANOST RADA