Inhibition of Armillaria and Heterobasidion growth by Penicillium adametzii isolated from Pinus sylvestris forest soil

Abstract

Summary Penicillium adametzii significantly inhibited the growth of Heterobasidium annosum sensu stricto on 2% potato dextrose agar after 10 days at 20–25°C. Chloroform extracts from P. adametzii culture filtrate and from culture grown on rice often decreased the dry weight of Armillaria colony and diameter of Heterobasidion colony in vitro. The effect depended on species and isolate of Armillaria, Heterobasidion and P. adametzii and concentration of the extract. Higher concentration of chloroform extract increased the dry weight of stems and roots of Pinus sylvestris plants inoculated with either of two isolates of Armillaria ostoyae and one isolate of Armillaria gallica. Lower concentrations of chloroform extract increased the dry weight of stems and roots of P. sylvestris inoculated with another isolate of A. gallica. Culture filtrate of P. adametzii decreased the length of necrosis on P. sylvestris stem inoculated with either of two of four isolates of H. annosum s.s., but if applied 1 month before inoculation, it increased the length of necrosis caused by another H. annosum s.s. isolate. Twenty fractions from the P. adametzii chloroform extract were separated by thin layer chromatography. Carboxylic acids, flavonoids and glycosides were detected in chloroform extract of P. adametzii by high performance liquid chromatography/mass spectrometer analysis. This is the first report of interactions between P. adametzii and either Armillaria or Heterobasidion with P. sylvestris.