Seed germination and development of crispy lettuce in response to the application of different doses of biostimulant

Abstract

The use of biostimulants in lettuce cultivation has become increasingly important due to the rising demand for high-quality vegetables. These biological compounds, such as Stimulate®, directly influence plant physiology by promoting growth and enhancing resistance to environmental stresses. The study aimed to evaluate the effects of different doses of Stimulate® on germination and development of curly lettuce (Lactuca sativa L.). The seeds were pre-soaked in various concentrations of the biostimulant (0.75, 1.0, 1.25, and 1.5 mL L⁻¹) and germinated in a BOD chamber. After transplanting, Stimulate® was applied through foliar spraying. Several parameters were assessed, including leaf number, plant height, head diameter, fresh weight, and dry weight. Seed germination, root length of seedlings, and agronomic traits such as leaf number, head diameter, and plant height were not significantly influenced by the doses of Stimulate®. In curly lettuce cultivation, doses of Stimulate® above 0.73 mL L⁻¹ and 0.49 mL L⁻¹ were detrimental to dry and fresh biomass accumulation, respectively.