Inter-relationship between shoot weight, severity of root rot and survival rate of subterranean clover inoculated with certain pathogenic fungi

Plant survival rate, root disease index and fresh shoot weight of subterranean clover seedlings inoculated with fungal pathogens (Fusarium avenaceum, F. oxysporum, Phoma medicaginis, Pythium irregulare and Rhizoctonia solani, both singly and in combinations) were generally inter-correlated over a wide range of temperature (10,15,20 and 25°C) and moisture conditions (45, 65% water holding capacity and flooding). There was a negative correlation between root disease index and shoot weight for all treatments except F. avenaceum + P. irregulare. Root disease index and seedling survival rate were negatively correlated except for F. oxysporum, Phoma medicaginis, P. irregulare and F. oxysporum + F. avenaceum. However, a good positive correlation was found between the survival rate and shoot weight for all treatments with the exception of Phoma medicaginis.