Effects of wood distillate and soy lecithin on the photosynthetic performance and growth of lettuce (Lactuca sativa L.)

This study investigated the effectiveness of foliar application of sweet chestnut wood distillate on the photosynthetic performance and growth of lettuce (Lactuca sativa L. cv ‘Canasta’), both alone and in combination with soybean lecithin used as biosurfactant. Seedlings of lettuce were treated with a foliar application of either mineral water (control), or 1:500 solutions of 3% soy lecithin, wood distillate and wood distillate plus 3% soy lecithin. After 1 week, the chlorophyll content, chlorophyll fluorescence, chlorophyll reflectance and dry biomass were measured. The results showed that both wood distillate and lecithin exerted a positive effect on chlorophyll content and biomass production, but the joint use of wood distillate and lecithin quickly stimulated a ca. 50% increase in these parameters and is thus recommended.