Disease Cycle and Epidemiology

Figure 9. Disease cycle of Monosporascus Root Rot and Vine Decline of Melons. (Courtesy R. Cohen, from Plant Disease 84:496.) A) Mature ascospores in soil; B) Germinated ascospore in the rhizosphere and attachment to a melon root; C) Necrotic lesions on melon roots; D) Above ground symptoms of vine decline and death; E) Perithecia formed in infected root tissue; F) Mature perithecium releasing ascospores into the soil.