Vpliv uporabe beljakovinskega hidrolizata pri povečani slanosti hranilne raztopine na pridelek vrtne solate (Lactuca sativa)

Dobrinja, Živa (author), Kacjan Maršić, Nina (mentor)

V magistrski nalogi smo proučevali vpliv uporabe proteinskega hidrolizata Delfan Plus V in povišane slanosti hranilne raztopine na rast, pridelek ter biokemične lastnosti vrtne solate (Lactuca sativa L.), pridelane v zaprtem hidroponskem sistemu NFT (nutrient film technique). Namen raziskave je bil ugotoviti, v kolikšni meri lahko dodatki biostimulanta, ki jih nanesemo foliarno (v koncentraciji 0,1 %) ali prek koreninskega sistema (v koncentraciji 1 %), ublažijo negativne učinke povečane koncentracije soli (40 mM NaCl) in izboljšajo kakovost pridelka. Poskus je potekal v zavarovanem prostoru Centra za proučevanje rasti in razvoja kmetijskih rastlin na Biotehniški fakulteti Univerze v Ljubljani. Uporabili smo pet enakih NFT-hidroponskih sistemov, v katerih smo spremljali osnovne fizikalno-kemijske parametre okolja in hranilne raztopine. V tehnološki zrelosti smo pobrali rozete solate in izvedli meritve rastnih parametrov (masa rozete, višinain premer rozete), klorofilnega indeksa, nitratov, suhe snovi in prolina kot kazalnika odziva solate na slanostni stres. Ugotovili smo, da je povečana slanost (40 mM NaCl) povzročila za 20 % manjšo povprečno maso rozet solate (382,8 ± 9,9 g) glede na kontrolne rastline (0 mM NaCl), ki so dosegle povprečno maso 482,1 ± 12,0 g. Dodajanje beljakovinskega hidrolizata ni značilno spremenilo masnih in morfoloških parametrov rozet solate. V rastlinah solate, ki smo jim biostimulant dodajali foliarno, je bila vsebnost nitratov značilno večja (2769,2 ± 242,7 mg/kg sveže mase) glede na rastline, ki so bile izpostavljene zgolj slanosti (1352,7 ± 497,0 mg/kg sveže mase) in glede na rastline z dodanim biostimulantom neposredno v hranilno raztopino (1240,1 ± 149,0 mg/kg sveže mase). Vsebnosti suhe snovi in prolina se med obravnavanji nista razlikovali, kar nakazuje, da stres ni bil dovolj intenziven ali pa je bil čas vzorčenja neustrezen.

• Language: Slovenian
• Keywords: solata, proteinski hidrolizat, slanostni stres, hidroponska pridelava
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Year: 2026
• PID: 20.500.12556/RUL-189121
• COBISS.SI-ID: 293516291
• Publication date in RUL: 02.10.2026

Secondary language

• Language: English
• Title: The effect of protein hydrolysate on lettuce (Lactuca sativa) yeld grown in nutrient solution with increased salinity

Abstract

In this master thesis, we investigated the effects of applying the protein hydrolysate Delfan Plus V and increasing the salinity of the nutrient solution on the growth, yield, and biochemical properties of lettuce (Lactuca sativa L.) grown in a closed NFT hydroponic system. The aim was to determine the extent to which biostimulant supplements, applied either foliarly (at 0.1%) or via the root system (at 1%), can mitigate the negative effects of increased salt concentration (40 mM NaCl) and improve crop quality. The experiment was conducted in a controlled environment at the Centre for the Study of Growth and Development of Agricultural Plants at the Biotechnical Faculty, University of Ljubljana. Five identical NFT hydroponic systems were used and the basic physicochemical parameters of the environment and the nutrient solution were monitored. Upon reaching technological maturity, the lettuce rosettes were harvested and cut, and growth parameters (rosette weight, height, and diameter) as well as the chlorophyll index, nitrate levels, dry matter content, and proline content, as an indicator of the lettuce response to salinity stress were measured and analysed. We found that increased salinity (40 mM NaCl) resulted in a 20% reduction in the average mass of lettuce rosettes (382.8 ± 9.9 g) compared to control plants (0 mM NaCl), which reached an average mass of 482.1 ± 12.0 g. The addition of protein hydrolysate did not significantly alter the mass or morphological parameters of the lettuce rosettes. In lettuce plants to which the biostimulant was applied as a foliar spray, the nitrate content was significantly higher (2,769.2 ± 242.7 mg/kg fresh weight) compared with plants exoposed to increased salinity (1,352.7 ± 497.0 mg/kg fresh weight) and plants to which the biostimulant was added directly to the nutrient solution (1,240.1 ± 149.0 mg/kg fresh weight). The dry matter and proline contents did not differ among the treatments, suggesting that the stress was not intense enough or that the sampling time was inappropriate.

• Keywords: salad, protein hydrolysate, salinity stress, hidroponic system