ABSTRACT

Five different Mississippi s soils (Bosket silty loam, Brooksville silty clay loam, Caledonia sandy loam, Grenada silty loam and Sharkey silty loam), were examined to determine disease severity and plant health on cotton in the presence of T. basicola and R. reniformis. Reductions in seedling survival, dry weight, and plant height occurred for the concomitant treatments. Disease severity, as measured by hypocotyl and root disease indices, and final population trends for both pathogens were similar. In biotron studies, R. reniformis was significantly increased in the presence of the fungus on Caledonia soil, but in the field plots only on Bosket and Grenada soils. No differences in fungal reproduction were detected in the field study, but in the biotron, final fungal populations were higher in the presence of the nematode on Bosket and Caledonia soils. Yield measured in the field plots was significantly higher in the control treatments on Bosket, Grenada, and Brooksville soils.