关键词: 西番莲, 花叶病抗性, 病情指数, 显微结构, 气孔, 物理防御

Abstract: Mosaic disease caused by viral infection is one of the key factors restricting the yield and quality of passion fruit (Passiflora edulis), and screening disease-resistant varieties is the fundamental solution. In this study, four major cultivated passion fruit varieties were used to evaluate the resistance differences to mosaic disease via mechanical inoculation with Cucumber mosaic virus (CMV). The leaf anatomical structures and micro-morphological characteristics of the four varieties were systematically compared using scanning electron microscopy and paraffin section techniques. Meanwhile, key morphological indicators related to mosaic disease resistance were screened through correlation analysis. The results showed that the leaf epidermis of disease-resistant varieties was covered with a uniform and dense flaky waxy layer, with relatively low stomatal density and stomatal size, thicker leaves and denser cell structure. Correlation analysis further confirmed that stomatal density and stomatal size were extremely significantly negatively correlated with disease resistance, while leaf thickness and compactness were significantly positively correlated with disease resistance. This study revealed that the resistance of passion fruit to mosaic disease is closely related to the physical defense structure of leaves. The key structural indicators screened can provide a reliable morphological basis for disease-resistant breeding of passion fruit.

Key words: passion fruit, mosaic disease resistance, disease index, microstructrue, stoma, physical defense