Pa. Mcgee et al., SURVIVAL OF PROPAGULES OF ARBUSCULAR MYCORRHIZAL FUNGI IN SOILS IN EASTERN AUSTRALIA USED TO GROW COTTON, New phytologist, 135(4), 1997, pp. 773-780
Soil-borne spores and hyphae of arbuscular mycorrhizal fungi are impor
tant propagules in cracking clay soils of northern NSW, Australia. In
these soils, senescent roots were uncommon. Although c. 4-200 spores g
(-1) soil were found, less than 6% established arbuscular mycorrhizas
in trap plants, and this percentage declined over 24 months. Using tet
razolium red as a vital stain, 16-21 % of spores from held soils were
found to be viable in fresh soil and 6-7 % after 24 months of storage.
Using fluorescein diacetate, the length of stained hyphae of c. 0 5 m
g(-1) soil was shown to be halved over 32 wk. The density of viable p
ropagules of arbuscular mycorrhizal fungi in soil declined over time a
nd was reduced by severe disturbance. The fungi that survived to 12 mo
nths included a species thought to form dormant spores, while those in
itiating infection after 24 months, did not.