Stres nedostatka dušika kod različitih genotipova graha

master's thesis

• Title (english): Nitrogen deficiency stress on three common bean genotypes
• Author: Ivana Štajcer
• Mentor: Boris Lazarević (mentor)
• Committee member: Boris Lazarević (predsjednik povjerenstva)
• Committee member: Sanja Sikora (član povjerenstva)
• Committee member: Klaudija Carović-Stanko (član povjerenstva)
• Granter: University of Zagreb; Faculty of Agriculture; (Department of Plant Nutrition); Zagreb
• Defense date and country: 2019-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Agronomy

Abstract

Nedostatak dušika (N) negativno utječe na sintezu fotosintetskih pigmenata kao i na svjetlosne tamne reakcije fotosinteze.
Cilj rada bio je analizirati utjecaj stresa nedostatka N-a na svjetlosne reakcije fotosinteze i Calvinov ciklus kod graha.
U pokusu su korištena tri genotipa graha: Trešnjevac, Zelenčec i Biser, prihranjivana s ½ Hoaglandove otopine (N+) te ½ Hoaglandove otopine bez dušika (N-). Mjerenje indeksa sadržaja klorofila, izmjene plinova i klorofilne fluorescencije provođeno je jednom tjedno tijekom četiri (4) tjedna uzgoja biljaka.
Utvrđeno je da postoje značajne razlike u indeksu sadržaja klorofila (CCI), maksimalnoj kvantnoj efikasnosti fotosustava dva (Fv/Fm) i intenzitetu fotosinteze (A) između istraživanih genotipova graha. Nedostatak dušika negativno je utjecao na CCI, A, provodljivost puči, Fv/Fm, a pri tom su najmanje promjene u A i Fv/Fm utvrđene kod genotipa Biser, te ovaj genotip možemo smatrati najtolerantnijim na nedostatak N. Nadalje, rezultati ukazuju da nedostatak dušika ima jači negativni utjecaj na sadržaj klorofila te na RuBisCo i druge enzime Calvinovog ciklusa, a slabiji utjecaj na fotokemijske reakcije, što je vjerojatno rezultat utjecaja nedostatka N na smanjenje sinteze proteina (enzima) uključenih u Calvinov ciklus.

Abstract (english)

Nitrogen deficiency has negative affects on photosynthetic pigments synthesis and photosynthetic dark and light reactions.
The aim of this study was to analyse the impact of nitrogen deficiency stress on chlorophyll fluorescence and gas exchange (Calvin cycle) on three bean genotypes.
Three common bean genotypes were used: Trešnjevac, Zelenčec and Biser. Treatments were represented as irrigated with ½ Hoagland's solution (N+) and pots irrigated with ½ Hoagland's solution without nitrogen (N-). Chlorophyll content, gas exchange and chlorophyll fluorescence were measured once a week during a period of four weeks.
Results have shown that there are significant differences in chlorophyll content index (CCl), maximal photochemical efficiency (Fv/Fm) and net photosynthetic rate (A) among investigated bean genotypes. Nitrogen deficiency had a significant negative impact on CCl, A, stomatal conductance, Fv/Fm, but those parameters (A and Fv/Fm) were least affected in genotype Biser, and this genotype we can consider the most tolerant on nitrogen deficiency stress. These results suggest that nitrogen deficiency had stronger negative effect on chlorophyll content, activity of RuBisCo and other Clavin cycle enzymes compared to photochemical reactions, which is probably the result of nitrogen deficiency on reduced synthesis of photosynthetic proteins include in Calvin cycle.

• Keywords: nedostatak dušika; genotipovi graha; svjetlosne reakcije fotosinteze; Calvinov ciklus
• Keywords (english): nitrogen deficiency; common bean genotypes; fluorescence and gas exchange parameters
• Language: croatian
• URN:NBN: urn:nbn:hr:204:903517
• Study programme: Title: Agroecology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/ magistra inženjer/inženjerka agroekologija (magistar/ magistra inženjer/inženjerka agroekologija)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2019-12-13 11:12:22