Transmission electron micrographs showing a cross-sectional view of Alternaria brassicae. Untreated (control) and treated with 50 mg/ml Ziziphus extract. Changes were observed in the conidia morphology including the sheath, cell wall, organelles, and cytoplasm of the hyphae. A. Longitudinal section of a mature conidia (X8000); B. The hyphal tip, in which showing a cluster of electron-dense vacuoles (yellow arrow), cell wall (W) and septa (S) are visible (X8000) and C. Cell wall and sheath of hyphal tip (X20000).