Ecology of the plant-feeding nematode fauna associated with sea buckthorn (Hippophae rhamnoides L. spp. rhamnoides) in different stages of dune succession

Abstract

Swnmary A field survey was carried out to investigate the development of the plant parasitic nematode fauna under Hippophae rhamnoides ssp. rhamnoides from the colonization to the degeneration stage. Sampies from different sand dune locations along the Dutch coast were analysed and the occurrence and densities of different nematode taxa were stuctied in relation to soil parameters and plant productivity, using ordination and regression techniques. There appeared to be a succession of nematode taxa a!ong with the development of soil and vegetation. The maturity index of the obligate plant-feeding nematode fauna and the mean number of species increased significantly. The characteristics of sites, with respect to soil parameters and nematode fauna, diverged as it reached the degeneration stage. Tyleru:horhynchus microphasmis Loof and Mesocriconema xenoplax (Raski) were common in aIl stages. The abundance of plant feeding nematodes in the rhizosphere of Hippophae increased towards larer stages in a succession gradient, whereas population densities in the bulk soil remained practically constant. The status of H. rhamrwides as a host of severa! free-living plant-feeding nematodes is discussed.