SUMM.i\RYWhole-body computed tomography X-ray scanning (X-ray CT) of wheat, cotton and radish gro-wing in pots containing 350 g of a white sand:clay niixtute produced images frotn which digital data of the volumetric water content were obtained. The volumetric w-ater contents were spatially heterogeneous around the toot and altered with the depth at which the image was taken. Data represent a ' snapshot in time' of the soil around single toots in a living soil-plant system.The volumetric water contents of soil around seedlings were assessed for the growth of two soil-borne fungi, Gaeumannomyces graminis var. tritici and Rhtzoctonici solani. The heterogeneity of water content was biologically significant: water contents around the roots of wheat, radish and cotton were of a great enough range to suggest the existence of heterogeneous sites in the rhizosphere which might favour or restrict fungal growth. In soil surrounding wheat roots, the most favourable regions for the growth of G. grammis were nearest the root, suggesting that the inner rhizosphere might be more amenable to tbe growth of this pathogenic fungus than the outer region of the rhizosphere, and the bulk soil.The technique of X-ray CT enables spatial examination of the response of soil water to environmental treatments of the soil-root system, and the non-destructive observation of the effect of the spatial heterogeneity of volumetric water content upon fungal growth in the soil, over time and at a range of depths.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.