Mineral nutrition in carnation tissue cultures under different ventilation conditions

Growth and propagation rates, hyperhydricity percentages, macronutrientabsorption and pH evolution were evaluated in Dianthuscaryophyllus CV Nelken cultured in vitro under different ventilationconditions. Culture in well ventilated conditions (HVC)i.e. low relativehumidity, generated lower percentages of hyperhydric explants, with highermicropropagation coefficients and dry weight increments, than in less ventilatedcultures (LVC). Macronutrient absorption was similar in both types of cultures,except for ammonium, nitrate, chloride and phosphate. In LVC, after 15 days ofculture, carnation explants absorbed more nitrate than ammonium and chlorideuptake was 5 times greater than in HVC. Phosphate uptake was more pronounced inLVC after 15 days of culture, reaching similar values in both types of culturevessels at the end of the experiment, and led to growth limiting conditions formore prolonged cultures. Medium pH decreased to acid values after 15 days ofculture and even more at the end of the experiment; however, these acidconditions seem not be an obstacle for nutrient absorption.