Changes in medium pH during white poplar micropropagation

Abstract

In this study, changes in the pH of the nutrient medium were investigated after 35 days of cultivation of four white poplar genotypes (Populus alba L.). Four initial pH values of the substrate were tested: 3.0, 4.0, 5.5 and 7.0 buffered sodium citrate buffer, as well as a standard medium for micropropagation with pH 5.5 without the addition of citric acid (control) The medium was sterilized in a microwave oven. The results of the variance analysis indicate that the final pH of the medium after cultivation, as well as the difference between the final and the initial pH of the medium, was significantly influence of initial pH, as well as the interaction of the genotype × medium, differences between genotypes in their reaction to the washed pH medium. On media with low initial pH was recorded positive, while the medium pH 7.0 was recorded negative change pH after cultivation. The results of the study indicate that changes in the pH of the medium during cultivation lead to a pH that is assumed to be optimal for their cultivation under in vitro conditions (cca. pH 5.5). The possibility of applying the obtained results in the improvement of the white poplar cultivation in vitro and the assessment of genotypes in melioration and phytooremediation projects is discussed.

U ovom istraživanju je ispitivana promena pH vrednosti hranljive podloge nakon 35 dana kultivacije četiri genotipa bele topole (Populus alba L.). Ispitane su četiri početne pH vrednosti podloga: 3,0, 4,0, 5,5 i 7,0 puferisane natrijum citratnim puferom, kao i standardna podloga za umnožavanje sa pH 5,5 bez dodavanja limunske kiseline (kontrola). Sterilizacija podloge je izvršena u mikrotalasnoj pećnici. Rezultati analize varijanse ukazuju da su konačni pH podloge nakon kultivacije, kao i razlika između krajnje i početne pH podloge veoma značajno zavisili od početne pH. Takođe je i interakcija genotip × podloga pokazala statistički znacajan uticaj na pomenuta svojstva. Na podlogama sa niskom početnom pH je zabeležena pozitivna, dok je na podlozi pH 7,0 zabeležena negativna promena pH tokom kultivacije. Rezultati istraživanja ukazuju da promene pH podloge tokom kultivacije vode ka vrednosti pH 5,5 za koju pretpostavljamo da bi bila optimalna za njihov uzgoj u uslovima in vitro (oko pH 5,5). Diskutovana je mogućnost primene dobijenih rezulata u unapređenju uzgoja bele topole in vitro i ocene genotipova u projektima melioracije i fitoremedijacije.