Protiglivna aktivnost bakterijskih izolatov rodu Bacillus iz cvetnega prahu

Bračič, Živa (avtor), Štefanič, Polonca (mentor), Zdovc, Irena (komentor)

Glivne bolezni čebelje zalege predstavljajo pomemben dejavnik zmanjševanja vitalnosti kolonij medonosne čebele (Apis mellifera), pri čemer izstopata poapnela zalega (povzročitelj Ascosphaera apis) in okamenela zalega (povzročitelja Aspergillus flavus in Aspergillus fumigatus). Protiglivno aktivnost 1182 sevov rodu Bacillus, izoliranih iz cvetnega prahu, smo ovrednotili z namenom določitve njene pojavnosti, intenzitete in širine ter preverjanja vpliva okoljskih dejavnikov (lokacija panjev in čas vzorčenja) in povezave med izraženo aktivnostjo in vrstno pripadnostjo sevov. Protiglivno aktivnost sevov smo določili s testi inhibicije rasti gliv v prisotnosti bakterij Bacillus sp. in jo ovrednotili z ordinalno lestvico stopenj inhibicije. Največji delež sevov bakterij je imel protiglivno aktivnosti proti A. apis, sledi aktivnost proti A. fumigatus, najnižji delež pa proti A. flavus. Najvišjo stopnjo inhibicije je doseglo 16,2 % sevov proti A. apis, 16,9 % proti A. fumigatus in 10,4 % proti A. flavus. Aktivnost proti vsem trem glivam je izkazovalo 13,6 % sevov, medtem ko 19,7 % sevov ni izkazovalo aktivnosti proti nobeni glivi. Sočasno pojavljanje aktivnosti med glivami je bilo šibko, kar potrjuje specifične profile delovanja sevov Bacillus sp. Lokacija vzorčenja je pomembno vplivala na pojavnost protiglivne aktivnosti, medtem ko vpliv obdobja vzorčenja ni bil statistično značilen. Rezultati kažejo, da se sevi rodu Bacillus razlikujejo tako v prisotnosti kot tudi v intenziteti protiglivne aktivnosti, pri čemer ima pomembno vlogo vrstna pripadnost. Vrsti Bacillus velezensis in Bacillus subtilis sta izstopali tako po deležu sevov z izraženo protiglivno aktivnostjo, kot tudi po njeni intenziteti. Sevi rodu Bacillus tako predstavljajo raznolik in taksonomsko specifičen vir protiglivno aktivnih bakterij z velikim potencialom za biološko obvladovanje glivnih bolezni čebel.

• Jezik: Slovenski jezik
• Ključne besede: protiglivna aktivnost, Bacillus sp., Ascosphaera apis, Aspergillus flavus, Aspergillus fumigatus, okamenela zalega, poapnela zalega, Apis mellifera
• Vrsta gradiva: Magistrsko delo/naloga
• Tipologija: 2.09 - Magistrsko delo
• Organizacija: BF - Biotehniška fakulteta
• Založnik: [Ž. Bračič]
• Leto izida: 2026
• PID: 20.500.12556/RUL-183992
• UDK: 579.24:582.8:638.178.2
• COBISS.SI-ID: 282884867
• Datum objave v RUL: 23.06.2026

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Antifungal activity of bee pollen Bacillus spp. isolates

Izvleček

Fungal brood diseases are a significant factor in the decline of honeybee (Apis mellifera) colony vitality, with chalkbrood (Ascosphaera apis) and stone brood (Aspergillus flavus, Aspergillus fumigatus) being the most prominent. We evaluated the antifungal activity of 1182 Bacillus strains isolated from pollen to determine their prevalence, intensity, and range, as well as to examine the influence of environmental factors (hive location and sampling time) and the relationship between expressed activity and the taxonomic affiliation of the strains. Antifungal activity was determined using inhibition tests and evaluated using an ordinal scale of inhibition levels. The highest incidence of activity of Bacillus sp. strains was against A. apis, followed by A. fumigatus, and the lowest against A. flavus. The highest inhibition level was achieved by 16.2 % of Bacillus sp. strains against A. apis, 16.9 % against A. fumigatus, and 10.4 % against A. flavus. Activity against all three fungi was exhibited by 13.6 % of the strains, while 19.7% of the strains showed no activity against any of the fungi. The overlap in activity among the fungi was weak, confirming the specific activity profiles of Bacillus sp. strains. The sampling location significantly influenced the occurrence of antifungal activity, while the effect of the sampling period was not statistically significant. Bacillus strains represent a diverse source of antifungal bacteria with potential for the biological control of fungal diseases in bees. The results show that strains of the genus Bacillus differ both in the presence and intensity of antifungal activity, with species affiliation playing a significant role. The species Bacillus velezensis and Bacillus subtilis stood out both in terms of the proportion of strains exhibiting antifungal activity and the intensity of that activity. Strains of the genus Bacillus thus represent a diverse and taxonomically specific source of antifungal bacteria with great potential for the biological control of fungal diseases in bees.

• Ključne besede: antifungal activity, Bacillus sp., Ascosphaera apis, Aspergillus flavus, Aspergillus fumigatus, chalkbrood, stonebrood, Apis mellifera