ASSESSMENT OF ARBUSCULAR MYCORRHIZAL FUNGI AS POTENTIAL BIOCONTROL AGENTS FOR POA ANNUA L. IN FINETURF

摘要

Experiments were performed to assess the effects of three arbuscular mycorrhizal (AM) fungalinocula, two (AMG1 and AMG2) derived from a golf putting green and one a species (Glomusmosseae) commonly found in golf greens, on the growth of Agrostis stolonifera and the weedgrass Poa annua. Shoot biomass production by P. annua grown as fine turf was significantlyreduced by addition of AMG1 to the rootzone substrate, whether phosphorus (P) was added tothe substrate or not. Shoot growth of A. stolonifera was reduced to a lesser extent by inoculationwith AMG1 in the lower-P treatment, but unaffected in that with added P. Shoot P concentrationwas unaffected by AM inoculation in the added-P treatments, but significantly increased in P.annua and decreased in A. stolonifera given no added P, suggesting that a reduced P supply mayplay a role in the growth reduction by AM fungi of A. stolonifera but not of P. annua. Thesecond putting green-derived inoculum, AMG2, significantly reduced shoot growth of perennial-type but not annual-type P. annua grown as individual plants, while G. mosseae increasedshoot biomass of both types significantly. Neither AMG2 nor G. mosseae had a significanteffect on A. stolonifera growth. These results suggest that carefully selected AM fungi showpotential as biocontrol agents for P. annua in fine turf, but that further research is required toisolate fungal species appropriate for control of different P. annua ecotypes.