Carbon dioxide enrichment promoted the growth, yield, and light‐use efficiency of lettuce in a plant factory with artificial lighting
Danyan Chen, Yanhao Mei, Liu Qi, WU Yong-jun, Zhenchao Yang
Abstract
Abstract Lettuce ( Latuca sativa L.) is a commercially important crop and a good candidate for production in a plant factory with artificial lighting (PFAL). To explore the influence of CO 2 enrichment (eCO 2 ) on lettuce growth, light‐use efficiency (LUE) and various aspects of the growth indicators were specifically assessed. Three CO 2 concentrations ([CO 2 ]): ambient CO 2 (as the control, approximately 400 μmol mol −1 ), approximately double the ambient (DA‐CO 2 , 800 ± 50 μmol mol −1 ), and approximately quadruple the ambient (QA‐CO 2 , 1600 ± 50 μmol mol −1 ) were applied for 30 d. The results indicated that plant height, stem diameter, number of leaves, root length, leaf width, and maximum leaf area were all positively related to [CO 2 ], which illustrated that growth was greater in the treatments with eCO 2 than under ambient CO 2 . The daily average assimilation rate (DAAR), the average dry weight growth rate (GRdw), and yield were also greater for plants grown under DA‐CO 2 and QA‐CO 2 than under ambient CO 2 (DAAR increased by 25.45% and 42.27%, GRdw increased by 28.76 and 37.55%, and yield increased by 33.65 and 44.16%, respectively). Light‐use efficiency increased by 28.51 and 41.12% for DA‐CO 2 and QA‐CO 2 compared with ambient CO 2 , respectively. We concluded that eCO 2 has the potential to enhance production as well as light utilization in PFAL.