Enzymatic activity of ectendomycorrhizal fungi

 Enzymatic (cellulolytic, pectolytic, proteolytic, chitinolytic and acid phosphatase) activities in the cultures of ten different ectendomycorrhizal strains (mainly Wilcoxina spp.) were studied. Although most of the fungi produced all these enzymes, their activities were low (milliunits per hour), with the exception of those of the pectolytic enzymes, which were detected at considerably higher levels (units per hour). Hebeloma crustuliniforme, an ectomycorrhizal fungus (positive control in our studies) synthesized ca. 2,000 times more exoglucanase than the ectendomycorrhizal fungi. Wilcoxina mikolae (ATCC 52685) had the lowest enzymatic activities of all 11 strains compared. Received: 3 December 1999     

Growth and spore germination of Cylindrocarpon destructans in associative cultures with bacteria and actinomycetes1

Studies were made on the effect of bacteria and actinomycetes on growth and spore germination of Cylindrocarpon destructans. The effect of bacteria on growth of this fungus as well as on spore germination was statistically not significant. The actinomycetes in general inhibited or had no influence on growth and germination of conidia of C. destructans.     

Chitinolytic and proteolytic activity of streptomycetes isolated from root-free soil,rhizosphere and mycorrhizosphere of pine (Pinus sylvestris L.)

Summary We tested 75 strains of Streptomyces spp. (25 taken from each environment of soil, rhizosphere, and mycorrhizosphere of pine, Pinus sylvestris L.) and all exhibited chitinolytic activity and hydrolysed gelatine and sodium caseinate in agar media. Enrichment of these media with glucose and NH₄NO₃ caused induction or stimulation of proteolytic Streptomyces spp. strains (80%) derived from root-free soil; inhibition of this activity was observed in most strains (92%) isolated from the root zone. The post-culture liquids of the rhizosphere strains cultured in the absence of glucose revealed a significantly higher proteolytic activity than those obtained from the root-free soil. The addition of glucose to the medium stimulated proteolytic activity in the post-culture broth of Streptomyces strains derived from soil and the mycorrhizosphere.     

Cellulolytic and pectolytic activity of streptomycetes isolated from root-free soil,rhizosphere and mycorrhizosphere of pine (Pinus sylvestris L.)

Summary Our studies have revealed that streptomycetes inhabiting root-free soil and the root zone of pine trees differ in their capacity to produce cellulolytic and pectolytic enzymes. Most of the root-zone organisms but only a few of the root-free soil isolates exhibited cellulolytic activity. A few of the root-zone organisms but no soil isolate showed pectolytic activity. In general the cellulolytic activity was higher in cellulase producers from the root zone than in those derived from the root-free soil. The streptomycetes studied produced only endopolymethylgalacturonase. The mean total activity of this enzyme was higher in the rhizosphere isolates but the mean specific activity was higher in the mycorrhizosphere organisms.     

Effect of pH,temperature and light on the pathogenicity of Cylindrocarpon destructans to pine seedlings in associative cultures with bacteria and actinomycetes1

The effect of pH, temperature and light on pathogenicity of two isolates of Cylindrocarpon destructans was studied. Both isolates were pathogenic to fir and pine seedlings. The degree of aggressiveness was affected by pH, temperature, light intensity and also by accompanying bacteria and actinomycetes.