Application of biopolymeric microcapsules in conventional lettuce growing

Salata (Lactuca sativa L.) sadrži bioaktivne spojeve koji su korisni za zdravlje ljudi, a povećanje njihove koncentracije postalo je cilj uzgojnih programa. Biopolimerne mikročestice jedan su od načina kako poboljšati morfološka (visina i promjer, biomasa i tržna masa rozete) i nutritivna svojstva (udjel suhe tvari, ukupni klorofil, ukupni polifenoli i flavonoidi i antioksidacijska aktivnost) salate. U ovom istraživanju postavljen je jednofaktorijalni pokus sa salatom sorte 'Melina' u tipu batavie. Prilikom sadnje presadnica, u tlo je inkorporirano osam vrsta biopolimernih mikročestica sastavljenih od nosača alginata s ili bez dodatnog kitozan omotača, s aktivnim tvarima: Ca2+, Cu2+, Ca2+/T. viride, Cu2+/T. viride. Primijenjena je i fiziološka otopina T. viride spora dok je kontrolna varijanta bila bez aplikacije mikročestica. Aplikacija mikročestica nije rezultirala značajnim razlikama u morfološkim svojstvima salate. Neinkapsuliranim sporama T. viride (u fiziološkoj otopini) ostvareni su značajno najveći prinos (6,82 kg m-2) i količina suhe tvari (7,07 %) u listovima salate. Primjena biopolimernih mikrosfera s aktivnom tvari Ca2+ dovela je do značajnog povećanja ukupnog klorofila (1862 μg⋅g-1·ST), ukupnih polifenola (4,58 mg EGK⋅g-1 ST) i flavonoida (9,65 mg EK⋅g-1 ST) te antioksidacijske aktivnosti (21,92 μmol ET g-1 ST) u odnosu na kontrolnu varijantu.Lettuce (Lactuca sativa L) contains several compounds that are useful in human health. Increasing concentrations of key healing compounds have become the goal of breeding programs. Application of biopolymeric microcapsules could improve morphologic characteristics (rosette height, diameter, biomass, and marketable weight) and nutritive characteristics (dry matter content, total chlorophyll, total polyphenols, total flavonoids and antioxidant activity) of lettuce. In this research, a one-factorial experiment with the batavia lettuce 'Melina' was set up. When planting seedlings, eight types of biopolymer microparticles made of sodium alginate as a carrier with or without chitosan coating with active ingredients Ca2+, Cu2+, Ca2+/T. viride, Cu2+/T. viride were incorporated into the soil. The physiological solution of T. viride spore was also applied while control was without applications of the microparticles. There was no significant difference in the morphological properties of the lettuce using the microparticles. The nonencapsulated T. viride (in saline solution) yields significantly highest yield (6,82 kg m-2) and significantly higher dry matter share (7,07 %). The application of biopolymer microspheres with the Ca2+ active agent resulted in a significant increase of total chlorophylls (1862 μg⋅g-1 dw), total polyphenols (4,58 mg EGK⋅g-1 dw), total flavonoids (9,65 mg EK⋅g-1 dw) and antioxidant activity (21,92 μmol ET g-1 dw) in comparison to the control variant