ISSN:
1420-9071
Keywords:
Fungal evolution
;
phytotoxins
;
host-selective toxins
;
Cochliobolus
;
Alternaria
;
fungal ecology
;
plant/fungal relationship
;
genetics of plant/pathogen relations
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract Many fungal pathogens of plants adapt readily to changes in agriculture. Among the most revealing is a fungal group whose species produce host-selective toxins as key determinants of disease. Several lines of evidence support the hypothesis that these fungi evolved from opportunistic, low-grade pathogens by gaining new genetic information leading to toxin production; in some species, toxin production is known to be under single gene control. as a result of this evolution, these fungi became virulent and host-specialized. The best-known model cases belong to the generaCochliobolus andAlternaria; there are suggestions of evolutionary lines among these genera, with species that range from saprophytes to opportunists to specialized pathogens. Host specialization can lead to genetic isolation, a first step in speciation. Ability to produce host-selective toxin has allowed these fungi to exploit the monocultures and genetic uniformity of modern agriculture. Destructive epidemics have been the result.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01922460
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