IN-VITRO CULTIVATION AND SPORULATION OF NEOZYGITES PARVISPORA (ZYGOMYCETES, ENTOMOPHTHORALES)

Neozygites parvispora was isolated from Thrips tabaci infesting leek p lants. In vitro cultivation of two isolates was achieved using supplem ented Grace's insect tissue culture medium complemented with fetal bov ine serum (FBS) and pre-treated lepidopteran hemolymph. This medium co mposition enabled exponential cell growth as rod-shaped hyphal bodies with a length over diameter ratio of 4.5-5.0. Both FBS and hemolymph w ere mandatory for sustained growth. The growth requirements indicate t he presence of one or several growth factors in both the hemolymph and FBS. Absence of FBS resulted in growth arrest with subsequent cell ly sis. Omission of hemolymph led to rounding and size decrease of the hy phal bodies, some of which formed septated germ tubes in a later stage . Eventually, cell death occurred under such conditions. Hyphal bodies from in vitro culture were capable of capilliconidia formation after entrapment in alginate pellets. This suggests the requirement of a liq uid/air interface, which triggers primary sporulation and subsequent c apilliconidium formation.