Nanosilica enhances growth, leaf epidermal traits, and disease resistance in Aglaonema cultivars

Abstract

Aglaonema is a high-value ornamental foliage plant showing considerable variation in growth and physiological responses among cultivars. Silica is a beneficial element that enhances plant growth, strengthens tissues, improves photosynthetic efficiency, and increases resistance to biotic and abiotic stresses. The effects of foliar application of nanosilica (SiO2) on growth, leaf epidermal characteristics, and disease resistance of Aglaonema were evaluated. The experiment was conducted using a split-plot design arranged in a randomized complete block design, with four nanosilica concentrations (0, 0.3, 0.6 and 0.9 g L-1) as main plots and sixteen cultivars as subplots. Significant differences among cultivars were found in plant height, number of leaves, leaf length, chlorophyll a, chlorophyll b, total chlorophyll, chlorophyll a/b ratio, and carotenoid content. Nanosilica at 0.3 g L-1 produced the highest in plant height, stomatal density, chlorophyll a/b ratio, and carotenoids, while 0.6 g L-1 enhanced epidermal thickness and chlorophyll content. The highest concentration, 0.9 g L-1, increased leaf length and width, stomatal index, and reduced incidence and severity of Lepidosaphes beckii, Ceroplastes rubens, Pseudococcidae, anthracnose, and stem rot. Interactions between cultivars and nanosilica were significant for leaf width, epidermal thickness, stomatal index, and stomatal density. Correlation analysis showed positive relationships among leaf size, plant height, stomatal density, and chlorophyll content. Considering consumer preference for compact plants with broad leaves and high resistance to pests and diseases, the foliar application of nanosilica at 0.9 g L-1 is deemed the most suitable concentration.