Abstract
The development of ectomycorrhizas on inoculated eucalypt seedlings in commercial nurseries is often slow so that only a small percentage of roots are mycorrhizal at the time of outplanting. If mycorrhizal formation could be enhanced by co-inoculation with bacteria which promote rapid root colonisation by specific ectomycorrhizal fungi, as demonstrated by certain bacteria in the Douglas fir-Laccaria bicolor association, this would be of advantage to the eucalypt forest industry. Two bacterial isolates with a demonstrated Mycorrhization Helper Bacteria (MHB) effect on ectomycorrhiza formation between Pseudotsuga menziesii and Laccaria bicolor (S238), and seven Western Australian bacterial isolates from Laccaria fraterna sporocarps or ectomycorrhizas were tested in isolation for their effect on ectomycorrhizal development by three Laccaria spp. with Eucalyptus diversicolor seedlings. Mycorrhizal formation by L. fraterna (E710) as measured by percentage infected root tips, increased significantly (p < 0.05) by up to 296% in treatments coinoculated with MHB isolates from France (Pseudomonas fluorescens Bbc6 or Bacillus subtilis MB3), or indigenous isolates (Bacillus sp. Elf28 or a pseudomonad Elf29). In treatments coinoculated with L. laccata (E766) and the MHB isolate P. fluorescens (Bbc6) mycorrhizal development was significantly inhibited (p < 0.05). A significant Plant Growth Promoting Rhizobacteria (PGPR) effect was observed where the mean shoot d.w. of seedlings inoculated only with an unidentified bacterium (Elf21), was 49% greater than the mean of uninoculated controls (-fungus, -bacterium). Mean shoot d.w. of seedlings coinoculated with L. bicolor (S-238), which did not form ectomycorrhizas with E. diversicolor, and an unidentified bacterium (Slf14) or Bacillus sp. (Elf28) were significantly higher than uninoculated seedlings or seedlings inoculated with L. bicolor (S-238) alone. This is the first time that an MHB effect has been demonstrated in a eucalypt-ectomycorrhizal fungus association. These organisms have the potential to improve ectomycorrhizal development on eucalypts under nursery conditions and this is particularly important for fast growing eucalypt species where the retention time of seedlings in the nursery is of short duration (2–3 months).
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References
Aggangan N S, Dell B, Malajczuk N and de la Cruz R E 1996 Soil fumigation and phosphorus supply affect the formation of Pisolithus-Eucalyptus urophylla ectomycorrhizas in two acid Philippine soils. Plant Soil 180, 259–266.
Bougher N L, Grove T S and Malajczuk N 1990 Growth and phosphorus acquisition of karri (Eucalyptus diversicolor F. Muell.) seedlings inoculated with ectomycorrhizal fungi in relation to phosphorus supply. New Phytol. 114, 77–85.
Bowen G D and Theodorou C 1979 Interactions between bacteria and ectomycorrhizal fungi. Soil Biol. Biochem. 11, 119–126.
Brundrett M, Bougher N L, Dell B, Grove T S and Malajczuk N 1996 Working with Mycorrhizas in Forestry and Agriculture. ACIAR Monograph 32. Australian Centre for International Agricultural Research, Canberra, Australia. 374 p.
Chanway C P, Radley R A and Holl F B 1991 Inoculation of conifer seed with plant growth promoting Bacillus strains causes increased seedling emergence and biomass. Soil Biol. Biochem. 23, 275–280.
Dell B and Malajczuk N 1997 Inoculation of eucalypts with Australian ectomycorrhizal fungi to increase productivity of plantations in Asia. Rev. For. Fr. 49, 174–184.
Duponnois R and Garbaye J 1990 Some mechanisms involved in growth stimulation of ectomycorrhizal fungi by bacteria. Can. J. Bot. 68, 2148–2152.
Duponnois R and Garbaye J 1991a Mycorrhization helper bacteria associated with the Douglas fir-Laccaria laccata symbiosis. Ann. Sci. For. 48, 239–251.
Duponnois R and Garbaye J 1991b Effect of dual inoculation of Douglas fir with the ectomycorrhizal fungus Laccaria laccata and mycorrhization helper bacteria (MHB) in two bare-root forest nurseries. Plant Soil 138, 169–176.
Duponnois R and Garbaye J 1992 Application des BAM (Bacteries auxiliaires de la mycorrhization) a l'inoculation du Douglas fir-Laccaria laccata S238 en pepiniere. Rev. For. Fr. 6, 491–500.
Duponnois R, Garbaye J, Bouchard D and Churin J L 1993 The fungus specificity of mycorrhization helper bacteria (MHBs) used as an alternative to soil fumigation for ectomycorrhizal inoculation of bare-root Douglas-fir planting stocks with Laccaria laccata. Plant Soil 157, 257–262.
Frey-Klett P, Pierrat J C and Garbaye J 1997 Location and survival of mycorrhiza helper Pseudomonas fluorescens during establishment of ectomycorrhizal symbiosis between Laccaria bicolor and Douglas Fir. Appl. Environ. Microbiol. 63, 139–144.
Garbaye J 1994 Tansley Review No. 76. Helper bacteria: a new dimension to the mycorrhizal symbiosis. New Phytol. 128, 197–210.
Garbaye J and Bowen G D 1987 Effect of different microflora on the success of ectomycorrhizal inoculation of Pinus radiata. Can. J. For. Res. 17, 941–943.
Garbaye J and Bowen G D 1989 Stimulation of ectomycorrhizal infection of Pinus radiata by some microorganisms associated with the mantle of ectomycorrhizas. New Phytol. 112, 383–388.
Garbaye J and Duponnois R 1991 Brevet France no 91 07882 du 26 juin 1991 au nom de 1'INRA: "Moyens pour ameliorer la croissance des plantes".
Garbaye J and Duponnois R 1992 Specificity and function of mycorrhization helper bacteria (MHB) associated with the Pseudotsuga menziesii-Laccaria laccata symbiosis. Symbiosis 14, 335–344.
Garbaye J, Churin J L and Duponnois R 1992 Effects of substrate sterilization, fungicide treatment, and mycorrhization helper bacteria on ectomycorrhizal formation of pendunculate oak (Quercus robur) inoculated with Laccaria laccata in two peat bare-root nurseries. Biol. Fertil. Soils 13, 55–57.
Hamblin A P 1981 Filter-paper method for routine measurement of field water potential. J. Hydrol. 53, 355–360.
Hardy G E St J and Sivasithamparam K 1985 Soil solarization: Effects on Fusarium wilt of carnation and Verticillium wilt of eggplant. In Ecology and Management of Soil-borne Plant Pathogens. Eds. C A Parker, A D Rovira, K J Moore and P T W Wong. pp 279–281. Am. Phytopath. Soc., St. Paul, MN, USA.
Jasper D A, Robson A D and Abbott L K 1987 The effects of surface mining on the infectivity of vesicular-arbuscular fungi. Aust. J. Bot. 35, 641–652.
Keuls M 1952 The use of the “studentized range” in connection with an analysis of variance. Euphytica 1, 112–122.
Malajczuk N, Molina R and Trappe J M 1982 Ectomycorrhiza formation in Eucalyptus. I. Pure culture synthesis, host specificity and mycorrhizal compatibility with Pinus radiata. New Phytol. 91, 467–482.
Mohammed G and Prasad R 1988 Influence of microbial fertilisers on biomass accumulation in polypotted Eucalyptus camaldulensis Dehn. seedlings. J. Trop. For. 4, 74–77.
Molina R and Trappe J M 1982 Patterns of ectomycorrhizal host specificity and potential amoung Pacific northwest conifers and fungi. For. Sci. 28, 423–458.
Molina R, Massicote H and Trappe J M 1992 Specificity phenomena in mycorrhizal symbioses: community-ecological consequences and practical implications. In Mycorrhizal Functioning: An Integrative Plant-fungal Process. Ed. M F Allen. pp 357–423. Routledge, Chapman and Hall, Inc., NY, USA.
Newman D 1939 The distribution of range in samples from a normal population, expressed in terms of an independant estimate of standard variation. Biometrika 31, 20–30.
O'Neill G A, Chanway C P, Axelrood P E, Radley R A and Holl F B 1992 An assessment of spruce growth response specificity after inoculation with coexistent rhizosphere bacteria. Can. J. Bot. 70, 2347–2353.
Pachlewski R and Pachlewska, J 1974 Studies on symbiotic properties of mycorrhizal fungi of pine (Pinus silvestris L.) with the aid of the method of mycorrhizal synthesis in pure cultures on agar. Forest Research Institute, Warsaw.
Probanza A, Lucas J A, Acero N and Gutierrez Mañero F J 1996 The influence of native rhizobacteria on european alder (Alnus glutinosa (L.) Gaertn.) growth. Plant Soil 182, 59–66.
Rennie R J (1981) A single medium for the isolation of acetylene-reducing (dinitrogen-fixing) bacteria from soils. Can. J. Microbiol. 27, 8–14.
Shishido M, Massicotte H B and Chanway C P 1996 Effect of plant growth promoting Bacillus strains on pine and spruce seedling growth and mycorrhizal infection. Ann. Bot. 77, 433–441.
Thomson B D, Grove T S, Malajczuk N and Hardy G E St J 1994 The effectiveness of ectomycorrhizal fungi in increasing the growth of Eucalyptus globulus Labill. in relation to root colonisation and hyphal development in soil. New Phytol. 126, 517–524.
Thomson B D, Hardy G E St J, Malajczuk N and Grove T S 1996 The survival and development of inoculant fungi on the roots of outplanted Eucalyptus globulus Labill. Plant Soil 178, 247–253.
Varese G C, Portinaro S, Trotta A, Scannerini S, Luppi-Mosca, A M and Martinotti M G. (1996) Bacteria associated with Suillus grevillei sporocarps and ectomycorrhizae and their effects on in vitro growth of the mycobiont. Symbiosis 21, 129–147.
Villeneuve N, Le Tacon F and Bouchard D 1991 Survival of inoculated Laccaria bicolor in competition with native ectomycorrhizal fungi and effects on the growth of outplanted Douglas-fir seedlings. Plant Soil 135, 95–107.
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Dunstan, W.A., Malajczuk, N. & Dell, B. Effects of bacteria on mycorrhizal development and growth of container grown Eucalyptus diversicolor F. Muell. seedlings. Plant and Soil 201, 241–249 (1998). https://doi.org/10.1023/A:1004329626763
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DOI: https://doi.org/10.1023/A:1004329626763