Studies on ectomycorrhiza

Summary Plants ofPicea abies (L.) Karst were grown in mycorrhizal association withTelephora terrestris (Pers. ex Fr.) andPisolithus tinctorius (Mich. ex Pers.) Coker and Couch on sphagnum peat in petri dishes or Perspex chambers. After 1 yearT. terrestris had formed prominent rhizomorphs which were characterized by light microscopy and investigated for³²P-orthophosphate uptake. The absorbed phosphate was transported to sinks throughout the rhizomorphal system as well as into the plant. The calculated translocation velocity and flux rate in the rhizomorph were in the range of 1–3 cm/h and 0.5–4.0 × 10^-10 mol cm^-2 s^-1, respectively. Label was observed to accumulate in the needles 2–3 days after application. Feeding a non-mycorrhized root with³²P-orthophosphate led to an accumulation of label in needles within 1 h, but no radioactivity appeared in the associatedT. terrestris rhizomorphs. The rhizomorphs ofP. tinctorius revealed a higher structural differentiation than those ofT. terrestris. Translocation of labelled phosphorus through rhizomorphs ofP. tinctorius into spruce needles was also demonstrated.