Effects of Boron Applications on Growth Traits of Lettuce (Lactuca Sativa L.) Grown in the Soil and Hydroponically

This study aimed to assess the effects of B addition on lettuce grown in soil and hydroponically and to determine the adequate B concentration enhancing plant growth and development. B concentration was measured in the soil (available and total B) and lettuce. Additionally, photosynthetic parameters (NDVI, total chlorophyll content, photosynthetic efficiency and performance index), and dry matter were measured in lettuce. The results showed that the lettuce B concentration increased with increasing B treatments in both experiences. The lettuce hydroponically grown has greater photosynthetic performance and dry matter content. However, a toxic effect was pronounced at high B treatment where B concentrations in lettuce were extremely high (196.4 mg/kg). This negatively impacts plant physiology. Thus, the optimal B concentration in lettuce hydroponically grown was determined to be 0.5 mg/kg. Regarding the soil grown lettuce, the low B treatment recorded the highest values for the physiological parameters, dry matter and lettuce B concentration. And no toxic effect was revealed at high B treatment. Total B and available B concentrations in the soil increased with B treatments. Soil available B concentrations ranged between 0.5 and 2.0 mg/kg considered a sufficient range for both treatments. Therefore, these results indicate that soil appears to be a better environment for the efficient growth of lettuce and acts as a buffer for nutrient problems and disease.