Effect of management practices on mycorrhizal infection, growth and dry matter partitioning in field-grown bean

The experiment was carried out on unsterilized field soil with low phosphor us availability with the objective of examining the effect of cultural prac tices on mycorrhizal colonization and growth of common bean. The treatments were: three pre-crops (maize, wheat and fallow) followed by three soil man agement practices ("ploughing", mulching and bare fallow without "ploughing " during the winter months). After the cultural practices, Phaseolus vulgar is cv. Canadian Wonder was grown in this soil. Fallowing and soil disturban ce reduced natural soil infectivity. Mycorrhizal infection of the bean root s occurred more rapidly in the recently cropped soil than in the fallow soi l. Prior cropping with a strongly mycorrhizal plant (maize) increased infec tivity even further.