Cultural Morphological Variations and Pathogenicity of Fusarium sp. Isolates causing fusarium wilt on some species of solanaceae in Syria

Abstract

Fusarium sp. is the most common disease cause of vascular wilt, mainly affecting vegetables, agricultural crops, perennial herbaceous plants and herbs.  63 samples were collected from different hosts (tomato, pepper and eggplant) planted in six Syrian provinces (Damascus, Rif-Demshq, Hama, Sweida, Lattakia and Tartous). 59 out of 63 isolates were successfully isolated, purified and morphologically characterized. 32 isolates were of F. solani (6 tomato, 25 Pepper and 1 Eggplant plant) and 26 isolates were of F. oxysporum (11 Tomato and 15 pepper plants). After 10 days, the growth rate of the fungal colonies on the nutrient culture was 4.5-9 cm for F. solani isolates and 5.6 - 9 cm for F. oxysporum isolates. Chlamydospores, Macroconidia and Microconidia were present in all isolates. The diameter of the small and large microconidia was intermediate 1.7- 6.22 × 2.9- 19.3 μm (F. solani) and between 1.5 - 7.7 × 2.8 -18.8 μm (F. oxysporum). Disease severity was measured of 48 isolates, so it was 21 isolates of F. oxysporum  infectious, with infection rate from 0.4 to 3.4 according to the ladder used, while 28 isolates of F. solani with infection rate from 3.6- 0.4. This is the first stage of studying the fusarium wilt disease in addition to the effectiveness of some biotic substances in stimulating and increasing the resistance of plants against this pathogen.