02895naa a2200421 a 450000100080000000500110000800800410001910000170006024501010007726000090017852017940018765000160198165000180199765000130201565000120202865000200204065000170206065000110207765000220208865000160211065000260212665000150215265000140216765000170218165000200219865300150221865300180223365300210225165300160227265300220228865300100231065300220232070000170234270000180235970000150237770000180239277300630241012786222024-05-21       1989    bl uuuu     u00u1 u    #d1 aPERRY, D. A.  aEctomycorrhizal mediation of competition between coniferous tree species.h[electronic resource]  c1989  aTo test the effect of ectomycorrhizal fungi (EMF) on interactions between host plants, Douglas-fir (Pseudotsuga menziesii) and pine (Pinus ponderosa) seedlings were grown in replacement series in pasteurized soil with: no EMF added; two EMF species added - Rhizopogon vinicolor (specific to Douglas-fir) and R. ochraceorubens (specific to pine); and four EMF species added - the two Rhizopogon species plus two host generalists, Laccaria laccata and Hebeloma crustuliniforme. A replacement series in unpasteurized forest soil was also included. Seedlings without added EMF were colonized by the greenhouse contaminant, Thelephora terrestris. Without added EMF (but with T. terrestris), the tree species mutually inhibited one another, producing relative yield totals significantly &lt1; with EMF added, mutual inhibition disappeared. With four EMF species added, Douglas-fir seedlings were significantly larger in mixture than in monoculture, with no corresponding decrease in the size of pine seedlings; this was due solely to seedlings with L. laccata, which apparently enhanced nitrogen (N) and phosphorus (P) uptake by Douglas-fir at the expense of luxury consumption by pine. Graphical analysis suggested that better growth of Douglas-fir in mixture with EMF added was related to improved P nutrition. Both N and P nutrition of pine was better in mixture with two than no EMF species added; there was no clear nutrient effect with four EMF species added. Results indicate that EMF can reduce competition between plant species and perhaps increase overall community P uptake. However, patterns were specific to both EMF and tree species and were quite different in unpasteurized soils. Hence generalizations about the effects of EMF on plant-plant interactions must be made cautiously.  aallelopathy  abiotechnology  aconifers  aecology  aectomycorrhizae  aforest trees  aOregon  aplant competition  apot culture  aPseudotsuga menziesii  aRhizopogon  aseedlings  awoody plants  aPinus Ponderosa  aCompeticao  aEctomicorriza  aFoliar nutrition  aMycorrhizas  aPhosphorus uptake  aPines  aSolo esterelizado1 aMARGOLIS, H.1 aCHOQUETTE, C.1 aMOLINA, R.1 aTRAPPE, J. M.  tNew Phytologist, New Yorkgv. 112, n. 4, p. 501-512, 1989.