Effect of Light Intensity and Foliar Application of Calcium Chloride and Naphthalene Acetic Acid on Growth and Yield of Strawberry cv. Paros

The role of calcium in the growth, fruiting and preservation of the quality of strawberries, has been well known. In this research, effect of calcium chloride along with naphthalene acetic acid (NAA) under shade conditions on growth, yield and quality of Paros strawberry was investigated. The experiment was a factorial with two factors of light intensity (normal light and shade condition) and calcium chloride and NAA treatment (control, 0.75% calcium chloride, 25 mg/L NAA, and 0.75% calcium chloride + 25 mg/L NAA). The results showed that spraying NAA and calcium chloride under shade conditions increased plant growth when compared with light conditions. Under normal light conditions, calcium chloride treatment increased the fruit diameter and yield in comparison with control treatment under light and shade conditions. The highest fruit firmness (342.0 N/cm2) was observed in the treatment of calcium chloride under light and shade conditions. NAA treatment under shade conditions resulted in higher anthocyanin. The treatment of calcium chloride + NAA in normal light condition showed higher total phenol (1.12 mg/g FW) and antioxidant activity (72.12%). Calcium chloride treatment increased the amount of calcium in the fruits by nearly 50%. Moreover, calcium chloride treatment in shade condition led to a 12% increase in calcium content of petiole, in comparison to those of control in shade condition. Calcium chloride along with NAA treatment increased leaf calcium compared to control treatment in light conditions. From the present results, it can be concluded that treatment of plant by calcium chloride alone in both light and shade conditions can increase the qualitative and quantitative characteristics of fruits of Paros cultivar of strawberry. Similarly, in some conditions, the use of NAA can, increase the absorption of calcium by the leaves.