Effects of Nutritional Amendments on Conidial Production of Fusarium solani f. sp. cucurbitae on Sodium Alginate Granules and on Control of Texas Gourd. G. J. Weidemann, Assistant Professor, Department of Plant Pathology, University of Arkansas, Fayetteville 72701. . Plant Dis. 72:757-759. Accepted for publication 25 April 1988. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/PD-72-0757.

Production of conidia by the fungus Fusarium solani f. sp. cucurbitae on sodium alginate granules was enhanced by the addition of nutritional amendments. The addition of 2% (w/v) ground oatmeal, cornmeal, or soy flour significantly increased conidial production on the surface of granules and resulted in higher soil populations than granular treatments without amendments or granules amended with carboxymethyl cellulose. More macroconidia were produced than microconidia with all treatments. Chlamydospores formed from hyphae and macroconidia for all treatments within 2 wk of soil application. Soil populations exceeded 2 × 10⁵ cfu/g of soil when granules were amended with cornmeal, oatmeal, or soy flour. Texas gourd control was greater than 80% when soy flour- or oatmeal-amended granules were applied preemergence at 220 or 440 kg/ha in greenhouse tests. In field studies, oatmeal- and soy flour-amended granules gave greater than 80% control of Texas gourd within 6 wk when applied preemergence at 220 kg/ha.

Keyword(s): biological control, Cucurbita texana, mycoherbicide.