Dose-Dependent Effect of ZnO Quantum Dots for Lettuce Growth

Zhihao Liang; Xiaoqin Pan; Wei Li; Erfeng Kou; Yunyan Kang; Bingfu Lei; Shiwei Song

doi:10.1021/acsomega.1c00205

Dose-Dependent Effect of ZnO Quantum Dots for Lettuce Growth

ACS Omega. 2021 Apr 11;6(15):10141-10149. doi: 10.1021/acsomega.1c00205. eCollection 2021 Apr 20.

Authors

Zhihao Liang¹, Xiaoqin Pan^{1

2}, Wei Li², Erfeng Kou^{1

2}, Yunyan Kang¹, Bingfu Lei^{1

2

3}, Shiwei Song¹

Affiliations

¹ College of Horticulture, South China Agricultural University, Guangzhou 510642, P. R. China.
² Key Laboratory for Biobased Materials and Energy of Ministry of Education, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, P. R. China.
³ Maoming Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong, Maoming 525100, P. R. China.

Abstract

As the cadmium-free semiconductor quantum dots, ZnO quantum dots (ZnO QDs) have wide potential applications in agriculture. However, the effects of ZnO quantum dots on crop growth and nutritional quality have not been fully studied. In this work, the lettuce was sprayed with different concentrations of ZnO QDs from 50 to 500 mg·L^-1 to evaluate their influence on lettuce antioxidant, biomass, and nutritional quality. The results showed that ZnO QDs existed in the lettuce in the form of Zn²⁺. Lettuce treated with 500 mg·L^-1 ZnO QDs would produce a large amount of reactive oxygen species (ROS), which adversely affected the absorption of nutrients, soluble protein content, and chlorophyll content, thus reducing plant biomass. When the concentrations range from 50 to 200 mg·L^-1, the antioxidant enzyme systems of lettuce were triggered to counteract the damage caused by excessive ROS. Moreover, ZnO QDs at this level promoted Ca, Mg, Fe, Mn, Zn, and B absorption and accumulation; increased soluble sugar content; and improved the lettuce biomass and nutritional quality.