Effects of light levels, quality and fertilizer rates on carrot (Daucus carota L.)

Karla E Christian, Tennessee State University


Carrot gas exchange rates are typically commensurate with environmental effects in the same way temperature responds to CO2. Carotenoids as reductants in carrot, D. carota L. improve carbohydrate formation over environmental effects when chemical energy splits H2O (via the reduction of CO2). It is hypothesized herein that carrot light levels conversion of CO2 to ½ O2 during sun and shade photoperiods do not physiologically differ at high intensity limits. Therefore, in this study, two carrot cultivars, Chantenay and Little Finger were evaluated and compared under relative light performance. Gas exchange rates were determined using water soluble fertilizer distributed into 3 equimolar concentrations for growth yields. Carrot foliage photosynthesis and intracellular CO2 gas exchange rates were measured as a function of light levels and quality at light absorption effects. The research was conducted at the Tennessee State University Agricultural Research and Demonstration Center in Nashville, TN. Greenhouse conditions were used to compare the overall quality and light levels effects on the carrots. Six seedlings of the carrot cultivars (Little Fingers and Chantenay) were potted in the greenhouse. The temperature inside the greenhouse ranged from 22°F to 37°F. Fertilizer treatment concentrations of 0.5, 1.0 and 1.5 T/gal. for sun and shade measurements were proportionally distributed into approximately 72 to 96 7 ½ inch pots. The average optimal gas exchanged for Little Fingers and Chantenay, occurred at 418.21 and 386.50 µmole of CO 2 m2/s in the sun and shade respectively for 2014 and 2015. CO 2:O2 gas exchanged rates for Chantenay and Little Fingers during the 2014 growing season in sun light levels and quality were significantly dependent on 1.0 T/gal. fertilizer concentration. Little Fingers and Chantenay shade intracellular gas exchange CO2 rates occurred at 400 µmole of CO2 m2/s and observed with 0.5 T/gal. and 1.5 T/gal. in 2014.

Subject Area

Plant sciences

Recommended Citation

Karla E Christian, "Effects of light levels, quality and fertilizer rates on carrot (Daucus carota L.)" (2015). ETD Collection for Tennessee State University. Paper AAI10120841.