Analiza lastnosti izolatov vrste Bacillus mycoides, pomembnih za varstvo rastlin pred patogeni

Dovjak, Rok (avtor), Mandić Mulec, Ines (mentor), Pompe Novak, Maruša (komentor)

Magistrsko delo preverja potencialno vzajemno delovanje med rastlino (Solanum tuberosum L., sorta Igor in genotip NahG-Rywal), bakterijo (Bacillus mycoides oz. Bacillus subtilis) in virusom PVYNTN. Pri izolatih iz rodu Bacillus smo izmerili koncentracije v gojišče izločene IAA in hidrolitskih encimov (proteinaza, hitinaza, celulaza). Na osnovi teh lastnosti izbranih bakterijskih sevov smo ugotavljali vpliv na rast in pojavljanje bolezenskih znamenj pri neokuženih in s PVYNTN okuženih rastlinah. Predpostavili smo, da se sevi B. mycoides (vrsta je v literaturi izpričana kot PGPR proti glivnim patogenom pri površinskem nanosu), izolirani na krompirišču na Nizozemskem, razlikujejo po sintezi IAA in hidrolitskih encimov, s krompirjem pa stopajo v simbiontski odnos in zavirajo virusno okužbo, zlasti tisti sevi, ki izločajo visoke koncentracije IAA. Ugotovili smo sortno različen odziv: pri sorti Igor so je pojavilo več različnih, po številu pa manj lezij kot pri transgenem genotipu NahG-Rywal, pri katerem so se bolezenska znamenja pogosto pojavila tudi na neinokuliranih listih. Substrat, bogat s hranili, ugodno vpliva na rast rastlin, pojava bolezenskih znamenj pa ne ustavi, ampak se število teh celo poveča. Po laboratorijskih analizah koncentracije IAA in encimov B. mycoides ni izkazal tako visokega PGP-potenciala kot B. subtilis, vendar je bilo in vivo pri sevih M2E-7 in M3E-14 zaznati nekatere ugodne učinke, npr. veliko prirast pri sorti Igor oz. dobro stanje lista pri sorti Igor in močan odziv v obliki lezij pri genotipu NahG-Rywal. Za uporabo pri varstvu rastlin so zanimive tudi nadaljnje raziskave sevov B. subtilis PS-216 in T16-8.

• Jezik: Slovenski jezik
• Ključne besede: varstvo rastlin, uporabna mikrobiologija, aplikacije v poljedelstvu, krompir, virus PVY, preobčutljivostni odziv, inducirana odpornost, indolocetna kislina
• Vrsta gradiva: Magistrsko delo/naloga
• Tipologija: 2.09 - Magistrsko delo
• Organizacija: BF - Biotehniška fakulteta
• Založnik: [R. Dovjak]
• Leto izida: 2019
• PID: 20.500.12556/RUL-111071
• UDK: 606:632.937:579.64:633.49(043.2)
• COBISS.SI-ID: 9361785
• Datum objave v RUL: 22.09.2019

DOVJAK, Rok, 2019, Analiza lastnosti izolatov vrste Bacillus mycoides, pomembnih za varstvo rastlin pred patogeni [na spletu]. Magistrsko delo. R. Dovjak. [Dostopano 5 maj 2025]. Pridobljeno s: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=slv&id=111071

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: The analysis of the Bacillus mycoides isolates improving plant defense against pathogenes

Izvleček

The master thesis examines the potential interaction between the plant (Solanum tuberosum L., cultivar Igor and genotype NahG-Ryawl), bacteria (Bacillus mycoides or Bacillus subtilis) and PVYNTN virus, by measuring concentration of IAA and hydrolytic enzymes (proteinase, chitinase, cellulase) in cell suspension and comparing growth and appearance of symptoms among uninfected and infected plants after addition of the suspension of various bacterial strains mentioned above. It was assumed that strains of B. mycoides (a species is widely recognized as PGPR against fungal pathogens when applied on leaves), isolated from a potato field in the Netherlands, differ in the production of IAA and hydrolytic enzymes, and that they develop a mutualistic relationship with potato plant meaning they can inhibit viral infection, especially the strains that excrete high concentrations of IAA. We have found a varietal difference in response: in Igor there is several types of lesions while there is only one in NahG-Rywal, but the latter exhibits more scarce response and occurrence of signs of infection on uninoculated leaves. Nutrients-rich substrate did not stop the spreading of infection but favorably affected the growth of young plants. B. mycoides by means of measured concentration of IAA and enzymes did not exhibit as high PGP potential as B. subtilis, but in vivo the strain of M2E-7 and M3E-14 exhibits some beneficial effects, for instance accelereted growth of cultivar Igor and good leave condition of cultivar Igor plus strong reaction in terms of lesions, seen in genotype NahG-Rywal, respectively. Strains B. subtilis PS-216 and T16-8 are apropriate for further analysis whether they could be used in crop protection products.

• Ključne besede: crop protection, applied microbiology, applications in agriculture, potatoe, virus PVY, hypersensitive response, induced resistance, indole acetic acid