All characters of living organisms. whether morphological, physiological, or biochemical, undoubtedly are genetically determined. The ability of a Eew microorganisms to attack a limited range of plant species and the within-species variation in disease development also are presumed to have genetic bases. Such a variation in disease expression was used to develop the gene-for-gene concept (Flor, 1955).
Leudders, V. D.
"Research Notes : The genetic basis of physiological races of phytophthora,"
Soybean Genetics Newsletter: Vol. 9
, Article 45.
Available at: http://lib.dr.iastate.edu/soybeangenetics/vol9/iss1/45