PHYTOALEXINS, RESISTANCE TRAITS, AND DOMESTICATION STATUS IN PHASEOLUS-COCCINEUS AND PHASEOLUS-LUNATUS

Resistance to pathogenic fungi and the isoflavonoids that confer such resistance capabilities were studied in two systems of wild and cultiv ated Phaseolus spp, seedlings. Results for P. coccineus show a gradien t in isoflavonoid diversity with pathogen resistance high in wild vari eties and low in cultivated ones. P. lunatus varieties showed the same trend in resistance and cyanogenic capacity, but not in isoflavonoid diversity. It is suggested that the effectiveness of the phytoalexin n atural mixture depends more on its diversity than its total levels in seedlings.