Nematode-Fungal disease complex involving Rotylenchulus reniformis and Macrophomina phaseolina on Helianthus annuus

Maximum reduction in plant growth characters was observed when nematode inoculated one week before the fungus. The intensity of charcoal rot increased considerably when nematode occurred simultaneously with the fungi (89.8%) or the nematode was inoculated one week prior to fungus (93.7%). Nematode population was found maximum when inoculated together or one week prior to fungus because of earlier establishment of nematode before fungus could cause appreciable damage. In general, fungi caused considerable reduction in nematode population.