Effects of salicylic acid and sucrose on pigment content in Pistacia chinensis leaves

Abstract

Pistacia chinensis leaves turn red or yellow in autumn due to changes in pigments. We investigated the effect of salicylic acid and sucrose on pigment in P. chinensis leaves. Different concentrations of salicylic acid (0.07 g/L, 0.14 g/L, and 0.21 g/L) and sucrose (6 g/L, 15 g/L, and 30 g/L) were sprayed on leaves at the hardening period, and the contents of total chlorophyll, carotenoids, anthocyanins, soluble sugar and soluble protein were determined. After spraying for 7 and 17 days, the total chlorophyll content following salicylic acid treatment (0.07 g/L) was higher than that following water treatment. After spraying for 24 days, the carotenoid content following most treatments reached the maximum, and the carotenoid content following the 0.14 g/L salicylic acid and 6 g/L sucrose treatments was significantly higher than that following water treatment. After spraying for 47 days, the anthocyanin content following salicylic acid and water treatments reached the crest value, and the anthocyanin content following the 0.07 g/L salicylic acid treatment was significantly higher than that following water treatment. After spraying for 55 days, the anthocyanin content of sucrose treatments reached the peak value, and the anthocyanin content following the 15 g/L and 30 g/L sucrose treatments was significantly higher than that follwing water treatment. In addition, the soluble sugar and soluble protein contents showed a significantly positive correlation with the anthocyanin content and a significantly negative correlation with total chlorophyll content. In summary, salicylic acid applied at 0.07 g/L at the onset of hardening period increased chlorophyll content of P. chinensis seedlings. Meanwhile, salicylic acid and sucrose applied at 0.14 g/L and 6 g/L respectively promoted the synthesis of carotenoids. Salicylic acid applied at 0.07 g/L and sucrose applied at 15 g/L or 30 g/L at the later hardening period increased anthocyanin accumulation of P. chinensis seedlings.