Search

Hidroponska pridelava zelenjave pridobiva vse bolj na pomenu, predvsem zaradi hitrejše rasti in razvoja rastlin in večjega pridelka. Kakovost hidroponsko pridelanih vrtnin je pogosto vprašljiva. V raziskavi nas je zanimalo, ali je hidroponsko pridelana solata po morfoloških in biokemijskih lastnostih primerljiva s solato pridelano v tleh. Od maja do julija 2021 smo izvedli poskus v rastlinjaku Biotehniške fakultete v Ljubljani. Postavili smo tri sisteme gojenja: plavajoč hidroponski sistem (Deep Water Culture), gredico, prekrito s črno-belo PE zastirko (folija) in neprekrito gredico (gola tla). Poskus je bil zasnovan v 4 ponovitvah, v vsaki po 24 rastlin 12 rastlin smo gojili do tehnološke zrelosti, 12 rastlin je bilo namenjeno tedenskemu vzorčenju. Na tedensko pobranih vzorcih in tehnološko zrelem pridelku smo izmerili morfološke lastnosti: maso nadzemnega dela (g), premer rozet (cm), višino stebla (cm) ter biokemijske parametre: spektrofotometrično meritev vsebnosti pigmentov, skupnih fenolnih spojin ter merjenje vsebnosti vitamina C s pomočjo tekočinske kromatografije. Izmerili smo tudi vsebnost vlage v pridelku. Tržna masa rozet v tehnološki zrelosti je bila na hidroponskem sistemu 420±60 g na foliji 369±30 g in na golih tleh 268±28 g. Značilno daljše (izdolženo) steblo so imele rozete solate pridelane na hidroponskem sistemu (8±1 cm) glede na solato pridelano na foliji (5±0 cm) in na golih tleh (4±0 cm). Sistem pridelave je značilno vplival na vsebnost skupnih fenolnih spojin, saj so imele rozete, pridelane v tleh, značilno več skupnih fenolnih spojin (na golih tleh 800±120 mg GAE/kg SM, na foliji 657±88 mg GAE/kg SM), glede na rozete iz hidroponske pridelave (422±67 mg GAE/kg SM). Sistem pridelave ni imel značilnega vpliva na vsebnost vlage v pridelku solat, ki je bila med 94,7 % v pridelku na hidroponskem sistemu do 95,05 % v pridelku na golih tleh. Hydroponic vegetable cultivation is becoming increasingly important, mainly due to faster growth and development of plants and higher yields. The quality of hydroponically grown vegetables is often questionable. In our research, we wanted to find out whether hydroponically grown lettuce is comparable to lettuce grown in soil in terms of its morphological and biochemical properties. In 2021, we conducted an experiment that took place from May to July in a laboratory field at the Biotechnical Faculty in Ljubljana. We established three growing systems: on a floating hydroponic system (Deep Water Culture), on a bed covered with black and white PE mulch (foil), and on an uncovered bed (bare soil). The experiment was laid out in 4 replicates, each with 24 plants 12 plants were grown to technological maturity, and 12 plants were scheduled for weekly sampling. Morphological characteristics were measured on the weekly sampled plants and the technologically mature plant: weight of the aerial part (g), diameter of the rosette (cm), height of the stem (cm) and biochemical parameters: spectrophotometric measurement of the content of specific pigments, total phenolic compounds, and vitamin C content measured by liquid chromatography. The moisture content of the plants was also measured on air-dried samples. The marketable mass of rosettes at the time of technological maturity was 420±60 g in hydroponics, 369±30 g on film and 268±28 g on bare soil. Rosette lettuce in hydroponics had a characteristic longer (elongated) stem (8±1 cm) compared to lettuce on film (5±0 cm) and on bare soil (4±0 cm). The cultivation system had a characteristic effect on the content of total phenolic compounds, as rosettes grown in soil had significantly more total phenolic compounds (on bare soil 800±120 mg GAE /kg DM, on film (657±88 mg GAE /kg DM) compared to hydroponic rosettes (422±67 mg GAE /kg DM). The growing system had no significant effect on the moisture content of the lettuce plant, which ranged from 94.7 % in hydroponic system to 95.05 % in bare soil culture.