Studies of nutrient requirements of lucerne on acid soils : A dissertation submitted in partial fulfilment of the requirements for the Diploma of Agricultural Science in the University of Canterbury [Lincoln College]

This work describes two pot trials conducted under glasshouse conditions on Omahau (pH 5.6), Grampians (pli 5.6) and Wolds (pH 6.2) soil from the McKenzie Country, South Island, New Zealand, to investigate the adaptability of lucerne to acid soil conditions. Lime, phosphorus and molybdenum were applied at two rates (none and some) to two varieties of lucerne of known different origin and characteristics, Narragansset (M. media Per.) and Tierra de Campos (M. sativa L.) grown on the three soils. Phosphorus and molybdenum were applied to subterranean clover (Trifolium subterraneum L.) cv. Mount Barker also grown on the three soils, to compare the responses to fertilisers of this legume, whose adaptability to acid soil conditions is well known, with the responses of lucerne and so determine what are the general nutrient requirements of these legumes and the specific requirements of lucerne. Phosphorus proved to be an essential element for the nodulation and growth of legumes on Omahau and Wolds soils. Subterranean clover shows a better ability than lucerne to get phosphorus from the Grampian soil which has a medium phosphorus level. Molybdenum was necessary on the three soils for getting maximum production of lucerne and subterranean clover. Lime was necessary for maximum production of lucerne on Wolds and Omahau soils. Although lucerne Tierra de Campos produced better than Narragansset, nothing can be concluded about their differences in adaptability to acid conditions