Effects of Biogas byproducts “three-dimensional” Fertilization on Yield and Quality of Lettuce

Abstract

Effect of three-dimension fertilizing mode (3-DFM) using CO 2 and liquid/solid fractions of the digesate from anaerobic digester was investigated in quality and yield of lettuce. CO 2 , solid fraction of digestate (SFD), and liquid fraction of digestate (LFD) were used as fertilizer for gaseous fertilizer, the base fertilizer, and foliar fertilizer, respectively. The result showed that the 3-DFM was appropriate for lettuce. Lettuce's plant height, width and number of leaves growth amount were 29.25 cm, 22.38 cm, and 16.2 cm, which were 26.8%, 16.5%, and 18.4% higher than the control, respectively. The overall yield of lettuce was 30.78% more than that of the control. The soluble sugar content and the chlorophyll content in lettuce was the highest, which were 29.4% and 11.4% higher than the control. Under the CO 2 and SFD condition, the content of vitamin C in lettuce, the content of free amino acid, crude protein and crude fiber contents of lettuce were the highest. The experimental study can provide an effective way to improve yield and quality of lettuce and utilize biogas plants wastes.