ENHANCING LETTUCE QUALITY THROUGH FOLIAR APPLICATION OF KAOLIN AND PLANT-BASED EXTRACTS
DOI:
https://doi.org/10.36103/3vz67339Keywords:
Leafy crops, Lettuce plant, Safe cultivation, Sustainable extractsAbstract
ABSTRACT
This study was conducted to improve lettuce plant quality using spraying with kaolin and Azolla and willow extracts. A factorial experiment was arranged in a randomized complete block design (RCBD) with three replicates, comprising three factors: foliar spray of kaolin (0 and 4 g L-¹), foliar spray of azolla extract (0, 3.75 and 7.5%) and foliar spray of willow extract (0, 3% leaf extract and 3% bark extract). The findings revealed that foliar application of kaolin significantly increased the phosphorus and calcium concentration (0.668 and 2.189%), leaf thickness (0.434 mm leaf-1), total chlorophyll (371.7 mg 100 g-¹ fresh weight) concentration and dry weight (1.620 g plant-1) and carotene (6.21 mg 100 g-¹ fresh weight) concentration respectively. While spraying with Azolla extract improved the phosphorus and calcium concentration, leaf thickness, leaf area, chlorophyll concentration, dry weight, and carbohydrates, while reducing the nitrate concentration by 0.710%, 2.497%, 0.446 mm leaf-1, 384.0 dm2 plant-1, 350.4 mg 100g-1 weight, 1.772 g plant-1, 17.59% and 0.14 mg g-1 dry weight, respectively, compared to the control treatment. Spraying with willow extract also increased phosphorus, calcium concentration (0.756, 2.415%), leaf area (374.69 cm² plant-¹), dry weight (1.687 g plant-1), and carbohydrate percentage (17.21%). Furthermore, the three-way interactions between the studied factors had significant effects on most of the measured traits, highlighting the importance of these treatments in improving the qualitative characteristics of lettuce.
Received: 3/5/2025
Accepted: 20/8/2025
Published: 31/8/2026
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