3. Mycorrhizas and oil palm
Most plant species form mycorrhizal symbioses and, therefore,
many crops could potentially benefit from inoculation with the
correct AMF inoculum. However, plants vary greatly in the degree
to which they benefit. This ranges from those that benefit little to
those that are strongly mycorrhizal dependent (Janos, 2007). In
fact,many of theworld’smajor food plants do not respond strongly
to inoculation with AMF and applications where they are clearly
beneficial are limited. In the case of oil palm, the limited
development of the root system, along with field observations
of high levels ofmycorrhizal colonisation, suggest that they benefit
greatly from the symbiosis.
The establishment of oil palm plantations puts pressure on
natural resources. In several countries oil palmis often planted into
cleared-cut land that previously supported other crops, or was
forested. The clearing of land to plant oil palm has resulted in
erosion of top soils by rain and severe leaching of the soil. It can
also result in loss of indigenousmycorrhizal fungi that reside in the
top soil. The combination of erosion and the nutrient depletion
means that the land has a limited capacity to support the growth of
either native or agricultural plants without the addition of
significant amounts of fertilizer. AMF have the potential to make
oil palm cultivation more sustainable and reduce the effects that
oil palm cultivation may have on ecosystems outside of the
plantation itself. Enormous amounts of P and N inorganic fertilizers