Utjecaj sunčevog zračenja na mesojednu biljku Drosera rotundifolia L.

master's thesis

• Title (english): Effect of solar irradiation on carnivorous plant Drosera rotundifolia L.
• Author: Marko Doboš
• Mentor: Mirta Tkalec (mentor)
• Committee member: Mirta Tkalec (predsjednik povjerenstva)
• Committee member: Renata Matoničkin Kepčija (član povjerenstva)
• Committee member: Mirjana Pavlica (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2012-02-17, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Okruglolisna rosika (Drosera rotundifolia L.) mesojedna je biljka svijetlih staništa koja su ugrožena zbog zaraštavanja. Čišćenjem staništa od visoke vegetacije biljke bi se trenutno opet našle u uvjetima visokog intenziteta svjetlosti. Cilj ovog rada bio je istražiti razlike između biljaka koje rastu u uvjetima nižeg intenziteta svjetlosti i onih koje rastu izložene prirodnom sunčevom zračenju te hoće li se i na koji način biljke koje su rasle u uvjetima nižeg intenziteta svjetlosti prilagoditi uvjetima prirodnog sunčevog zračenja. Biljke koje su godinu dana bile izložene vanjskim atmosferskim prilikama bile su većih dimenzija i proizvele su cvjetne stapke. Imale su nižu koncentraciju svih fotosintetskih pigmenata, ali bez promjena u učinkovitost fotosustava II što ukazuje na prilagodbu fotosintetskog aparata. Također, nađena je povećana koncentracija fenolnih spojeva - tanina, fenolnih kiselina, antocijana i flavonoida koji imaju ulogu u zaštiti od prejakog osvjetljenja, UV stresa, ali i oksidacijskog stresa. Biljke koje su bile naglo izložene direktnom sunčevom zračenju pet sati dnevno tijekom ljeta u trajanju od tjedan dana su se, nakon početnog stresa koji je doveo do fotoinhibicije, nakon sedam dana prilagodile i zaštitile od svjetlosnog i UV stresa povećanjem koncentracije spomenutih fenolnih spojeva, osobito tanina i flavonoida među kojima posebno antocijana. Također došlo je do promijene omjera fotosintetskih pigmenata jer se smanjio udio klorofila, a povećao udio karotenoida što je zajedno sa sintezom zaštitnih spojeva dovelo do prilagodbe fotosintetskog aparata i oporavka fotosinteze.

Abstract (english)

Roundleaf sundew (Drosera rotundifolia L.) is a carnivorous plant of sun exposed habitats that is threatened by overgrowth. After removing tall plants from habitat sundews would be instantly exposed to high light intensity levels again. Purpose of this experiment was to examine differences betwen plants that are growing in low light intensity and the ones that are growing exposed to natural solar irradiation and whether and how plants that grew in low light intensity would adapt to a solar irradiation exposure. Plants that were exposed to outer atmospheric conditios during one year were larger and also produced flower stalks. They had lower concentration of all photosynthetic pigments, but without changes in efficiency of photosystem II which indicates adaptation of photosynthetic apparatus. Also, higher concentration of phenols was found – tannins, phenolic acids, anthocyanins and flavonoids that could contribute in protection from high light intensities, UV stress, but also oxidative stress. Plants that were suddenly exposed to direct solar irradiation five hours a day during one week in summer, after initial stress that led to photoinhibition, adapted after seven days of exposure and developed protection from light and UV stress by increasing concentration of phenols, particularly tannins and flavonoids, especially anthocyanins. Exposure also led to a change in photosynthetic pigments ratio because chlorophylls decreased, and carotenoids increased, which together with synthesis of protective compounds led to adaptation of photosynthetic apparatus and recovery of photosynthesis.

• Keywords: Drosera rotundifolia L.; okruglolisna rosika; sunčevo zračenje; svjetlosni stres; fotosintetski pigmenti; fenolni spojevi
• Keywords (english): Drosera rotundifolia L; roundleaf sundew; solar irradiation; light stress; photosynthetic pigments; phenolic compounds
• Language: croatian
• URN:NBN: urn:nbn:hr:217:848510
• Study programme: Title: Ecology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra ekologije i zaštite prirode (magistar/magistra ekologije i zaštite prirode)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-04-28 12:50:49