Abstract
Magnaporthe grisea produced phialides and microconidia. Some of isolates, which possesed mating ability, from various gramineous plants; finger millet, rice, wheat, Oryza longistaminata, Eriochloa villosa, Panicum bisulcatum, Digitaria sanguinalis, D. smutsii, D. horizontalis and Brachiaria plantaginea had phialide and microconidium production potential. The phialide is darkly pigmented, vase-shaped, spherical to obclavate, with tapered apex, terminal collarette, basal septum, thick-walled, 5.9-12.5 (mean 8.9) μm long, 3.3-7.2 (4.5) μm thick in the broadest part, arising solitarily or sympodially from aerial hyphae. Microconidia are hyaline, cylindrical, rounded at the end first, then lunate with thin cell wall, no septum, 5-8 (mean 6) μm long, 0.5-0.8 (0.7) μm wide and with one nucleus. The first rod-shaped microconidium is formed blastically from the conidiogenous cell apex within the collarette. Successive rod-shaped microconidium is formed blastically from alternate sides of the conidiogenous cell. Subsequent microconidia are produced from the same locus. Accumulated curved microconidia form a globose mass, rarely with slime, at the tip of a phialide. Each conidium continues to grow and then secedes. The shape of the microconidia becomes crescent. Light does not affect microconidium formation. Oatmeal agar and potato dextrose agar are suitable for microconidium production.
