Factors associated with soil receptivity to some fungal root rot pathogens of peas uri icon

abstract

  • The relationship between various abiotic and biotic soil factors and the capacity of the soil to allow soil-borne pathogens to produce disease ('soil receptivity', SR) was investigated for three major pea root rot pathogenic fungi. Several relationships were established. SR to Thielaviopsis basicola was shown to be positively associated with the abundance of pseudomonads, soil pH, organic matter content and C/N ratio. The number of saprophytic Fusarium solani in the rhizoplane was higher in soil less conducive to F. solani f. sp. pisi, whereas the abundance of indigenous F: solani in the rhizosphere was unrelated to receptivity. The amounts of soluble K, P, Mg and total C and N in soil, individually, were higher with increasing conduciveness to F: solani f. sp. pisi. The SR to Aphanomyces euteiches was not well associated with any soil aspect investigated, except Gliocladium in the rhizoplane and Acremonium in the rhizosphere, of which populations were higher in soil less receptive to this pathogen. Experiments with soil sterilization showed that soil biota were the main factor responsible for the inhibition of investigated pathogens. Therefore, despite its correlation with chemical and physical factors, SR to the investigated pathogens can be considered essentially of microbiological nature. (C) 1998 Elsevier Science B.V.

publication date

  • 1998
  • 1998