Efficacy and Soil Persistence of Fusarium solani f. sp. cucurbitae for Control of Texas Gourd (Cucurbita texana). G. J. Weidemann, Assistant Professor, Department of Plant Pathology, University of Arkansas, Fayetteville 72701. G. E. Templeton, University Professor, Department of Plant Pathology, University of Arkansas, Fayetteville 72701.. Plant Dis. 72:36-38. Accepted for publication 8 September 1987. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/PD-72-0036.

Fusarium solani f. sp. cucurbitae (F. s. f. sp. cucurbitae) effectively controlled Texas gourd (Cucurbita texana) when applied as preplant-incorporated conidial suspensions or as preemergence applications of F. s. f. sp. cucurbitae-infested sodium alginate granules amended with nutritional substrates. Suspensions of either microconidia or macroconidia at 3 × 10¹³/ha, alone or in combination with trifluralin at 1 kg a.i./ha, provided significant control of sequentially planted Texas gourd up to 12 wk after application. F. s. f. sp. cucurbitae-infested sodium alginate granules amended with 2% (w/v) soy flour or 2% (w/v) ground oatmeal at 110 or 220 kg/ha provided greater control for a longer period than did conidial applications. Initial control levels exceeding 80% declined to 50–70% within 12 wk at the highest application rates. Soil populations of F. s. f. sp. cucurbitae declined more than 90% within 6 wk when applied as conidial suspensions. Soil populations from granular applications increased for the first 6 wk, followed by rapid declines.

Keyword(s): biological weed control, mycoherbicide.