Respiration Rate and Shelf Life of Radish (Raphanus sativus L.) as Influenced by Postharvest Application of Calcium Nitrate and Humic Acid Concentration

Abstract

Postharvest application of calcium has a significant effect on postharvest quality and
respiration rate of some horticultural crops. However, there is little literature citing
the effect of calcium and humic acid on the respiration rate and shelf life of radish
during storage. Hence, a study was conducted to assess the efficacy of calcium
nitrate and humic acid on respiration rate and shelf life of radish. The experiment
was laid out in a completely randomized design (CRD) with four treatments and
three replications. The treatments tested were composed of calcium nitrate, and
humic acid concentration applied alone and in combination and control. Data on
visual quality rating, sprouting, shelf life, color changes, CO2 concentration and
respiration rate were subjected to the analysis of variance for CRD. Radishes
applied with varying postharvest treatment were significantly different regarding
sprouting and shelf life during storage but not significant regarding the visual quality
rating. The color value of radish decreases as the storage days increases. The
decrease in the value of color indicated a loss of whiteness of radish. Also, CO2
concentration and respiration rate remarkably influenced by the application of
calcium nitrate and humic acid. Thus, application of calcium nitrate and humic acid
alone or in combination is beneficial in improving the respiration rate and shelf life
of radish.