Tipi ektomikorize na bukvi (Fagus sylvatica L.) v naravnem in gospodarskem gozdu : doktorska disertacija

Grebenc, Tine (avtor), Kraigher, Hojka (mentor), Regvar, Marjana (član komisije za zagovor), Kajba, Davorin (član komisije za zagovor)

Glive predstavljajo ključno povezovalno biotsko komponento med posameznimi elementi gozdnega ekosistema, predvsem med viri hranil in drevesnimi partnerji v simbiozi - ektomikorizi. Spremenjene razmere v okolju, zaradi naravnih sprememb ali človekovih vplivov se odražajo tudi na ektomikorizi. Za sledenje spremembam in njihovo potencialno uporabo za mikobioindikacijo je nujno poznavanje vrstne sestave populacije ektomikoriznih gliv. V našem delu smo na ploskvah z različnimi vplivi (naravna ali antropogena sestojna vrzel, ploskev z dvakratno koncentracijo ambientalnega ozona) spremljali pojavljanje ektomikoriznih gliv na bukvi. V standardizirano odvzetih vzorcih zemlje določevali, kvantificirali, z indeksi pestrosti prikazali spremembe v populaciji ektomikoriznih gliv na bukvi in drugih drevesnih partnerjih na ploskvah ter z metodo ordinacije korelirali pojavljanje z nekaterimi lastnostmi ploskev, kjer smo odvzemali vzorce. Osredotočili smo se na čim uspešnejše določevanje tipov ektomikorize, zato smo uporabili kombiniran pristop določevanja po anatomskih lastnostih tipov in določevanje s primerjavo PCR-RFLP vzorcev z lastno bazo podatkov in s primerjavo pomnoženih nukleotidnih zaporedij z javno dostopnimi bazami. Na vseh ploskvah smo tudi popisovali in herbarizirali trosnjake ektomikoriznih in domnevno ektomikoriznih vrst gliv kot referenčni material za PCR-RFLP bazo. Različni pristopi pri določevanju ektomikorize so pričakovano rezultirali v večjem deležu do vrst ali do rodu določenih tipov ektomikorize kot v primerljivih študijah, zaradi uporabe molekularnih pristopov. Pomembna je predvsem primerjava z PCR-RFLP bazo, ki vsebuje referenčni material lokalnega izvora. V mali sestojni vrzeli smo opazili statistično značilne spremembe v pojavljanju in indeksih pestrosti predvsem v novo nastali antropogeni vrzeli Snežna jama, kjer še ni prišlo do naravne regeneracije, ki na drugih ploskvah zabriše spremembe. Na pojavljanje tipov ektomikorize ima vpliv število drevesnih patnerjev na ploskvi in prisotnost vrzeli , kar smo pokazali tudi z metodo ordinacije. Rezultati enoletnega vzorčenja na ploskvi s povišano koncentracijo ozona niso pokazali značilnih razlik v številu in vrstni sestavi tipov ektomikoriz med tretiranimi drevesi in kotrolnimi ploskvami.

• Jezik: Slovenski jezik
• Vrsta gradiva: Doktorska disertacija
• Tipologija: 2.08 - Doktorska disertacija
• Organizacija: BF - Biotehniška fakulteta
• Kraj izida: Ljubljana
• Založnik: [BF, Interdisciplinarni podiplomski študij biotehnologije]
• Leto izida: 2005
• Št. strani: XII, 174 f., [34] f. pril.
• PID: 20.500.12556/RUL-15231
• UDK: 581.557:582.632.2(043.3)
• COBISS.SI-ID: 1505190
• Datum objave v RUL: 11.07.2014

Sekundarni jezik

• Jezik: Angleški jezik

Izvleček

Fungi represent an important link between several biotic components of forest ecosystem with sources of nutrients in ectomycorrhiza. Natural or anthropogenic changes in environment can be detected as drift within functional and/or population diversity of macro- and microsymbionts. Identification of symbionts to the species level is crucial for following the drift in population structures from differently stressed plots in micobioindication approach. The aim of our research was to identify and describe species of ectomycorrhizal fungi forming symbiosis on beech and to briefly analyse ectomycorrhizae of other tree hosts from differently stressed research plots. Research plots with natural occurring or man made small canopygaps and a plot with ozonated canopies of trees, were selected. Soil samples for analysis were collected using standardised procedure. Ectomycorrhizae was identified and counted in all soil samples. Biodiversity indices were calculated and ordination method was applied to show changes in population structure of ectomycorrhizae. Combined approach for identification of ectomycorrhizae was applied with an aim to identify as many as possible different types of ectomycorrhizae to the species level. Anatomical identification in combination with PCR-RFLP and sequencing were applied. On all plots sporocarps of ectomycorrhial species were mapped and reference fungal material was stored in herbarium for build-up of PCR-RFLP database. Different approaches for identification of ectomycorrhizae resulted in higher proportion of types of ectomycorrhizae identified to the species or to the genus level in comparison to some comparable studies. The PCR-RFLP database isof high importance for identification since it contains the reference material from the same locations as an ectomycorhiza originate. Significant difference was observed in small man-made canopy gaps for occurence and diversity indices compared to plots with at least some natural regeneration. Ordination method revealed significant influence of number of tree partners and presence of canopy gap on the number of vital types of ectomycorrhizae counted in soil samples. After one year sampling on research plot fumigated with double ambient ozone concentration no significant differences were observed compared to control plot in species composition and in number of vital types of ectomycorrhizae.