Xh. Lu et al., MYCORRHIZA FORMATION AND GROWTH OF EUCALYPTUS-GLOBULUS SEEDLINGS INOCULATED WITH SPORES OF VARIOUS ECTOMYCORRHIZAL FUNGI, Mycorrhiza, 8(2), 1998, pp. 81-86
As many eucalypts in commercial plantations are poorly ectomycorrhizal
there is a need to develop inoculation programs for forest nurseries.
The use of fungal spores as inoculum is a viable proposition for low
technology nurseries currently producing eucalypts for outplanting in
developing countries. Forty-three collections of ectomycorrhizal fungi
from southwestern Australia and two from China, representing 18 gener
a, were tested for their effectiveness as spore inoculum on Eucalyptus
globulus Labill. seedlings. Seven-day-old seedlings were inoculated w
ith 25 mg air-dry spores in a water suspension. Ectomycorrhizal develo
pment was assessed in soil cores 65 and 110 days after inoculation. By
day 65, about 50% of the treatments had formed ectomycorrhizas. By da
y 110, inoculated seedlings were generally ectomycorrhizal, but in man
y cases the percentage of roots colonized was low (<10%). Species of L
accaria, Hydnangium, Descolea, Descomyces, Scleroderma and Pisolithus
formed more ectomycorrhizas than the other fungi. Species of Russula,
Boletus, Lactarius and Hysterangium did not form ectomycorrhizas. The
dry weights of inoculated seedlings ranged from 90% to 225% of the uni
noculated seedlings by day 110. Although plants with extensively colon
ized roots generally had increased seedling growth, the overall mycorr
hizal colonization levels were poorly correlated to seedling growth. S
pecies of Laccaria, Descolea, Scleroderma and Pisolithus are proposed
as potential candidate fungi for nursery inoculation programs for euca
lypts.