Germination of old seeds of various halophytes occurring on the Slovenian coast

Diplomsko delo temelji na analizi kalivosti starih semen petindvajsetih vrst halofitov, ki uspevajo pretežno v slanih obalnih habitatih slovenskega primorja. Srčika diplomskega dela je empirične narave. Analiza kalivosti zajema več metodoloških korakov, kot so priprava semen in pogojev za kalitev, razporejanje semen v petrijevke in postavitev v rastno komoro, opazovanje in sprotno beleženje rezultatov v določenem časovnem razponu, statistična obdelava podatkov, prikaz rezultatov kalivosti v grafični obliki in izdelava dendrogramov. Sledi diskusija o rezultatih in preverjanje predhodno zastavljenih hipotez. Rezultati, dobljeni z analizo kalivosti starih semen halofitov, so primerjani z rezultati kalivosti istih semen, ko so bila le ta sveža oziroma stara nekaj mesecev. Cilj je ugotoviti, ali stara semena še ohranjajo sposobnost kalitve, s čimer lahko sklepamo tudi na njihovo dolgoživost oziroma kratkoživost. Med drugim sem želela raziskati razlike med sposobnostjo kalitve starih semen halofitnih enoletnic in halofitnih trajnic ter drobnih, številnih semen in velikih, manj številnih semen. Pri vrstah, ki so vzkalile, sem primerjala njihovo stopnjo kalivosti v odstotkih, potek oziroma hitrost kalitve ter dan, ko je bila opažena prva kalica. Rezultati analize so v splošnem pokazali, da sposobnost kalitve semen upada sorazmerno s starostjo. Prav tako sem ugotovila, da stara semena halofitnih trajnic kalijo bolje kot stara semena halofitnih enoletnic. Med slednjimi ni vzkalila nobena vrsta. Kljub ugotovitvi, da stara semena mnogih halofitnih trajnic ostanejo viabilna več let, njihova sposobnost kalitve z leti upada. Med kalivostjo drobnih in številnih semen ter kalivostjo velikih in manj številnih semen nisem opazila razlik, glede na katere bi lahko sklepala o večji sposobnosti kalitve prvih ali drugih. Vzkalilo je devet vrst od petindvajsetih, pri čemer sem lahko našla podobnosti v poteku in dnevih pričetka kalitve, prav tako so vse vzkaljene vrste dosegle svojo maksimalno stopnjo kalitve v obdobju treh tednov.The graduate thesis is based on the analysis of old seed germination of twenty-five species of halophytes, which mainly grow in saline coastal habitats on Slovenian littoral. The heart of the thesis is empirical nature. Analysis of germination includes several methodological steps, such as the preparation of seeds and germination conditions, distribution of the seeds in the dishes and placing them in a growing chamber, observation and realtime recording of results in a given timeframe, statistical treatment of data, results shown in graphic form and dendrogram construction, followed by discussion of the results and verification of predetermined hypotheses. Results obtained from the analysis of old seed germination of halophytes are compared with the results of the germination of the same seeds, when they were fresh or few months old. The aim is to determinate whether the old seeds still retain the ability to sprout, so we can conclude on their longevity or shortevity. Among other things, I wanted to explore the difference between the capacity of old seeds germination of halophyte annuals and perennials, and different sized seeds. For species that germinated, I compared their rate of germination percentage, the course and speed of germination and the date when the sprouts were first observed. The analysis results in general showed that the germination capacity of seeds decrease proportionally with age. I also found that the old seeds of halophyte perennials germinate better than old seeds of halophyte annuals. Among the annuals none of them germinated. Despite finding that the old seeds of many saltmarsh remain viable for several years, their germination capacity decline with age. During germination of numerous tiny seeds and germination of large and less numerous seeds I didnt notice any difference. Nine out of twentyfive species germinated, and I was able to find similarities in the course of days and the beginning of germination, as well as all the species that germinated has reached the maximum level of germination in period of three weeks