Light regulation of quality and growth of basil

Abstract

Basil suffers from chilling injury (CI) when stored at temperatures below 10-12 °C which seems related to the imbalance between reactive oxygen species (ROS) and antioxidants. We hypothesized that increased light intensity applied shortly before harvest (EOP, End-Of-Production) increases nutritional value i.e. carbohydrates and antioxidants. This could improve the chilling tolerance. Two basil cultivars were grown in a vertical farming set-up at a light intensity of 150 µmol m -2 s -1 . During the last 5 days of growth, EOP light treatments ranging from 50 to 600 µmol m -2 s -1 were applied. Postharvest the leaves were stored at 4 or 12 °C in darkness. Higher EOP light intensity increased antioxidants as total ascorbic acid, rosmarinic acid as well as carbohydrate contents at harvest. During storage antioxidants decreased more rapidly at 4 than at 12 °C. However, increased EOP light intensity did not alleviate chilling symptoms suggesting a minor role of antioxidants studied against chilling stress.