Growth of white clover in undisturbed soils after inoculation with efficient mycorrhizal fungi

Abstract

Clover seedlings were inoculated with the indigenous or one of three introduced mycorrhizal fungi and transplanted into undisturbed cores of eight hill country soils. After several harvests, at least one of the introduced fungi had increased shoot growth in each soil from between 16 to 117%. In most soils, the growth benefit from inoculating with an introduced mycorrhizal fungus tended to decrease after the initial shoot harvest, and was then maintained at a lower level over subsequent harvests. In a Taihape silt loam, however, the growth benefit from Glomus tenuis inoculation increased steadily over six harvests. In four out of five soils, previous application of phosphate fertiliser (50 kg P/ha/year) did not reduce mycorrhizal growth responses.