Acremonium Species as the Causal Agent of Muskmelon Collapse in Spain. J. GARCIA-JIMENEZ, Departamento de Production Vegetal, Universidad Politecnica de Valencia, Camino de Vera 14, 46020 Valencia, Spain. M. T. VELAZQUEZ, C. JORDA, and A. ALFARO-GARCiA, Patologia Vegetal, Departamento de Production Vegetal, Universidad Politecnica de Valencia, Camino de Vera 14, 46020 Valencia, Spain. Plant Dis. 78:416-419. Accepted for publication 30 November 1993. Copyright 1994 The American Phytopathological Society. DOI: 10.1094/PD-78-0416.

Over the last decade, a new disease of muskmelon (Cucumis melo) has appeared in the coastal Mediterranean areas of Spain where early melons are produced in the field. The economic losses are severe, and the disease is spreading to new areas. The aim of this research was to describe the disease and conduct Koch's postulates to show an Acremonium sp. to be the causal agent. This fungus has not previously been reported to cause a similar disease on melon. The obvious aboveground symptom of the disease is a sudden collapse of the plant when the first fruit is ripening. Root symptoms appear soon after planting and include yellow discoloration and corking of the upper root, generalized death of secondary roots, and continuous production of superficial roots. Characteristically, there are no aerial symptoms, plant decline, stunting, or slow growth until wilting occurs. The disease may be named Acremonium melon collapse to avoid confusion with any other disease characterized by a sudden nonvascular wilt.