[Truncated] The symbioses between both Rhizobium leguminosarum bv. trifolii and Trifolium subterraneum L. (subterranean clover) and Bradyrhizobium sp. (Lupinus) and Lupinus angustifolius L. have been integral to agricultural production in Australia's Mediterranean climate regions. The symbiosis between B. sp. (Lupinus) and L. angustifolius has been associated with higher and more consistent levels of N2 fixation than the symbiosis between R. l. bv. trifolii and subterranean clover in south-western Australia over a prolonged period. This has occurred under conditions that include interruption of the symbiosis by rotational practices and summer drought and infrequent reinoculation with elite strains of root nodule bacteria.This study sought to explain differences in symbiotic performance between R. l. bv. trifolii and B. sp. (Lupinus), in terms of the persistence of their populations under selection pressures encountered in the presence or absence of their legume host. Persistence was defined in relation to abundance in soil and consequent nodulation of the host legume and the genetic profile and N2 fixing effectiveness of isolates recovered from nodules.
|Qualification||Doctor of Philosophy|
|Publication status||Unpublished - 2002|