Susceptibility of immature soybean leaves to Phytophthora species

摘要: Abstract In an earlier study it was demonstrated that fully expanded leaves of soybean cv. Harosoy 63 ( Rps 1) and rps are respectively resistant susceptible to Phytophthora megasperma f.sp. glycinea race 1. the present immature trifoliolate both cultivars were this pathogen. They also two isolates from Douglas fir, partially capsici parasitica . comparison, primary isolates, highly resistant, with only traces infection, These observations suggest spp possess varying degrees accommodation soybean, even though is normally a host for The possibility susceptibility due deficiencies in metabolic precursors required expression resistance glyceollin synthesis tested by supplying range compounds prior inoculation. included sugars, growth factors. Only glucose, galactose sucrose clearly effective, they promoted 1 Harosoy. cvs supplied associated accumulation significant levels glyceollin. More immediate ineffective, discussed glucose functions as source energy development responses or leaf maturation rather than precursors.