Evaluation of Different Sources and Levels of Pyroligneous Acid on Growth Yield and Resistance to Insect Pests and Diseases of Sweet Pearl (F1) Corn

Abstract

Background: In the Philippines, one of the most significant agricultural products is corn (Zea mays L.). Wood vinegar, or pyrolyzed biomass, is a liquid byproduct of biomass pyrolysis that contains a complex mixture of organic acids, phenolic compounds, and volatile bioactive constituents. Aims: To evaluate the effects of different sources and levels of pyroligneous acid (PA) from kakawate and coconut husk on reducing pest and disease incidence, enhanced growth, and yield of corn (Zea mays L.), with the goal of identifying environmentally safe alternatives for enhancing corn productivity. Study Design: A 2 × 4 factorial experiment arranged in a split-plot design was employed over a 1,000 m² experimental area. The experimental area was first divided into two main plots, to which the two PA sources (kakawate and coconut husk) were randomly assigned. Each main plot was then subdivided into four subplots, where the PA application levels (0, 100, 150, and 200mL L⁻¹ water) were randomly allocated. Place and Duration of Study: The study was conducted at the Corn Production Area, Mindoro State University, Philippines, from February 3 to May 5, 2024. Methodology: Corn plants was treated with PA according to the assigned source and level combinations. Data were collected on pest incidence (harmful and beneficial insect population), disease occurrence (leaf blight, leaf spot), growth parameters (plant height, stem diameter, ear length and width), and yield parameters (husked and unhusked ear weight, fresh and dry biomass, and yield per plot). Statistical analyses were performed to determine significant differences among treatments (p ≤ 0.05). Results: Corn treated with PA from coconut husk (A2) exhibited significantly lower pest and disease incidence, including resistance to corn borer, armyworm, leaf blight, and leaf spot. Growth and yield parameters were also enhanced, with taller plants, wider stems, longer and wider ears, and heavier biomass and yield per plot. Application of 150 mL PA L⁻¹ of water (B3) further improved pest and disease resistance, growth, and yield. The combined treatment of coconut husk PA at 150 mL L⁻¹ (A2B3) consistently produced the most favorable results, showing the highest resistance to pests and diseases and the greatest improvements in growth and yield parameters. Conclusion: Pyroligneous acid from coconut husk applied at 150 mL L⁻¹ of water effectively enhances corn resistance to pests and diseases while promoting growth and yield. These findings suggest that PA at appropriate concentrations can serve as a potential environmentally friendly pest repellent, disease defense, and bio-stimulant, offering practical recommendations for sustainable corn production and improved farm profitability.