Fotomorfogeneza motovilca (Valerianella locusta (L.) Laterr.) ob podaljševanju dneva s svetlobo različne spektralne sestave

Poplašen, Suzana (author), Vodnik, Dominik (mentor), Kump, Bojka (comentor)

V diplomski nalogi smo ugotavljali odzive motovilca pri dosvetljevanju z različnimi svetlobnimi obravnavami. Cilj poskusa je bil, da s podaljšanjem dneva povečamo pridelek motovilca, ne da bi ta prešel v rast v višino (izdolževanje) oz. v cvetenje. V poskusu, ki smo ga februarja in marca 2019 opravili v rastlinjaku Oddelka za agronomijo Biotehniške fakultete, smo uporabili motovilec sorte 'Vit', ki smo ga izpostavili trem svetlobnim tretmajem. V prvem obravnavanju smo dan podaljšali za dve uri s svetlobo, sestavljeno iz kratkovalovne rdeče, bele in modre svetlobe (R+W+B); v drugem smo 2-urno podaljšanje izvedli s svetlobo iz dolgovalovne rdeče, bele in modre svetlobe (FR+W+B), pri čemer je bila gostotota toka fotosintetsko aktivnih fotonov podobna kot pri prvem obravnavanju (PPFD = 170-200 µmol m-2 s-1). Zadnje obravnavanje, kontrola, ni bilo dosvetljevano. Rastline smo dosvetljevali 45 dni in v tem času izvedli 4 vzorčenja. Dosvetljevane rastline so imele v povprečju večjo svežo in suho maso ter prirast od nedosvetljevanih. Najboljše rezultate v teh parametrih so dosegale rastline dosvetljevane s FR+W+B svetlobo. Njihova sveža masa je znašala 2,7 g/na rastlino, suha pa 0,45 g/na rastlino. Nedosvetljevane rastline so imele najnižjo maso, sveža je znašala 2,2 g/na rastlino, ter suha 0,32 g/na rastlino. Rastlinam, dosvetljevanim s FR+W+B svetlobo, so poleg največje sveže in suhe mase največ prirastli tudi rastni vršički. Merili so 11,9 mm in skupno prirastli glede na izhodiščno stanje T0 za 117 %. Vršički rastlin, ki so bili dosevtljevani z R+W+B svetlobo, so prirastli za 115 %, s tem, da so rastline dosvetljevane z R+W+B svetlobo bolj enakomerno priraščale med vzorčenjem. Nedosvetljevani vršički so prirastli za 93 %. Rastline vseh treh obravnavanj so prirastle največ med terminoma T0 in T1. Rezultati so pokazali, da svetlobne obravnave bistveno ne vplivajo na število listov ali skupno površino le teh. Med svetlobnimi obravnavami prav tako nismo zasledili velikih razlik v fotosintetski aktivnosti, kar pripisujemo dejstvu, da so bile rastline večino časa izpostavljene enaki naravni svetlobi.

• Language: Slovenian
• Keywords: dosvetljevanje, kratkovalovna rdeča, dolgovalovna rdeča, fitokrom, motovilec, LED sistem
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Publisher: [S. Poplašen]
• Year: 2019
• PID: 20.500.12556/RUL-110100
• UDC: 635.57:581.1/.5:535-2(043.2)
• COBISS.SI-ID: 9286777
• Publication date in RUL: 12.09.2019

Secondary language

• Language: English
• Title: Photomorphogenesis of lamb's lettuce (Valerianella locusta (L.) Laterr.) under day prolonged by light of different spectral composition

Abstract

Our thesis addressed the growth response of the plant lamb’s lettuce to different light treatments. The aim of this study was to achieve an increase in the yield by extending the photoperiod with supplemental lighting without getting into extension growth or reaching the flowering phase. In the experiment that was conducted in February and March of 2019 in a greenhouse of the Department of Agronomy at the Biotechnical Faculty, cultivar 'Vit' was used. The plants were exposed to three different light treatments. In the first one, the day was prolonged for two hours with combination of red, white and blue light (R+W+B); in the second one, the two hours supplemental lighting included far-red, white and blue light (FR+W+B) and in the third treatment, the control plants were not treated with additional lighting. The supplemental lighting, for which we used light-emitting diodes (LED), was, in both treatments, applied in Photosynthetic photon flux density (PPFD) of 170-200 µmol m-2 s-1. During the 45-days period 4 measurements were taken. The results have shown that on plants treated with supplemental lighting had higher fresh and dry weight and higher extension of the shoot apex. The highest average results in these parameters were observed in plants given the supplement lighting treatment of FR+W+B. Their fresh weight was 2.7,7 g/plant and dry weight was 0.,45 g/plant. Plants cultivated under no supplemental lighting had the lowest fresh (2.2 g/plant) and dry (0.32 g/plant) weight as well as the least grown shoot apex. The highest results in fresh and dry weight corresponded with the extension growth of the shoot apexes of plants under FR+W+B treatment. The length of them were 11,9 mm and their growth from the starting point was 117 %. The shoot apexes of plants under R+W+B lighting treatment achieved an average growth of 115 %. During the experiment the apex elongation was most even under R+W+B. The shoot apex of control plants elongated for 93 % during experiment. The observed plants have shown the biggest growth during the period between T0 and T1. The results have shown that extending the photoperiod with supplemental lighting does not significantly affect the number of leaves or their total surface area. Furthermore, no significant differences in photosynthetic rate were observed between light treatments, which could be attributed to the fact that all plants were for the most part of the light period exposed to equal amounts of sunlight.

• Keywords: supplemental lighting, red light, far-red light, phytochrome, lambs lettuce, LED system