Fotosintezne lastnosti dveh žlahtniteljskih linij navadne konoplje (Cannabis sativa L.)

Eržen, Jan Jurij (author), Vodnik, Dominik (mentor)

Znanstvenih poročil o fotosintezi konoplje (Cannabis sativa L.) je razmeroma malo. Raziskali smo razlike v fotosinteznih lastnostih dveh žlahtnjiteljskih linij (MX-CBD-11 in MX-CBD-707), ki po morfoloških lastnostih ustrezata dvema podvrstama konoplje, ssp. sativa in ssp. indica. Fotosintezo smo merili z aparatom Li6400xt (LiCor,USA) v vegetacijskem obdobju in v obdobju cvetenja. Primerjali smo izmerjene parametre fotosinteze v realnih razmerah rastne komore (A), fotosintezno kapaciteto (Amax), odziv fotosinteze na jakost svetlobnega toka (AQ krivulja), odziv fotosinteze na različne koncentracije CO2 (ACi krivulja). V vegetativni fazi je bila netofotosinteza linij A(MX-CBD-11)=9.76 ± 0.91 µmol CO2 m-2 s-1 in A(MX-CBD-11)= 11,57 ± 0,91 µmol CO2 m-2 s-1. Tudi ob cvetenju smo večje vrednosti fotosinteze izmerili pri MX-CBD-707 kot pri MX-CBD-11 (10,69 ± 1,53 vs. 8,00 ± 0,91 µmol CO2 m-2 s-1). Svetlobna saturacijska točka je bila pri obeh linijah pri PPFD 600 µmol m-2 s-1. V razmerah svetlobne nasičenosti in ob povečanem CO2 je fotosinteza dosegala v povprečju 30 µmol CO2 m-2 s-1, včasih pa presegla 36 µmol CO2 m-2 s-1. Žlahtniteljski liniji se nista razlikovali v parametrih ACi in AQ krivulj, smo pa opazili razlike v celičnem dihanju (Rd) in prevodnosti listnih rež (gs). Razlike v realni fotosintezi se niso prenesle direktno v pridelek, saj so rastline MX-CBD-11 imele bistveno večjo biomaso. Gre za različne vzorce alokacije ogljika pri obeh linijah.

• Language: Slovenian
• Keywords: konoplja, fotosinteza, fotosintetska kapaciteta, svetlobna krivulja fotosinteze, CO2 krivulja fotosinteze
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Publisher: [J. J. Eržen]
• Year: 2019
• PID: 20.500.12556/RUL-113386
• UDC: 633.52:581.132(043.2)
• COBISS.SI-ID: 9377913
• Publication date in RUL: 28.12.2019

Secondary language

• Language: English
• Title: Photosynthetic traits of two breeding lines of cannabis (Cannabis sativa L.)

Abstract

Scientific information on hemp (Cannabis sativa L.) photosynthesis is relatively scarce. We investigated photosynthetic traits of cannabis, comparing two morphologicaly distinct breeding lines (MX-CBD-11 in MX-CBD-707) which have characteristics of two subspecies ssp. sativa and ssp. indica. Plant photosyntetic parameters were measured with Li6400xt (LiCor, USA) at vegetative and flowering stage. Photosynthetic rate at chamber conditions (A), photosynthetic capacity (Amax), photosynthetic light response (AQ) curves and photosynthetic CO2 response (ACi) curves, were compared. Photosynthetis of MX-CBD-11 and MX-CBD-707 were 9,76 ± 0,91 µmol CO2 m-2 s-1 and 11,57 ± 0.91 µmol CO2 m-2 s-1, respectively, at the vegetative stage, but higher photosynthetic rates in MX-CBD-707 compared to MX-CBD-11 were found at reproductive stage (10,69 ± 1,53 vs. 8,00 ± 0,91 µmol CO2 m-2 s-1). Light saturation of photosynthesis occured at 600 µmol PPFD. Under saturating light conditions and elevated CO2 plant photosynthesis averaged 30 µmol CO2 m-2 s-1 with maxima at 36 µmol CO2 m-2 s-1. Breeding lines did not differ ACi and AQ parameters, but exibited differences in respiration (Rd) and stomatal conductance (gs). Differences in A did not translate in biomass produciton as the breeding line MX-CBD-11 significantly surpassed MX-CBD-707 in overall biomass. Differences in flower to stem ratio's and root mass, suggest different carbon alocation patterns of the breeding lines.

• Keywords: cannabis, photosynthesis, photosynthetic capacity, light response curves, CO2 response curves