The effect of sulphur, nitrogen fertilization and inoculation with Rhizobium meliloti, on the growth and chemical content of alfalfa and sweet clover in pot culture
Abstract
It is a well known fact that applications of sulphur to
sulphur-deficient soils will very substantially increase the
growth of legumes. However, applications of sulphur on the
same soils do not necessarily increase the grain production of
of cereal crops.
Previous workers have suggested that the marked effects of
sulphates on leguminous plants can result either from a fertilizer
action on tbe host plant, or through their influence on the growth
of nodule bacteria.
One of the major objectives in this study was to establish
which, if either, of these two factors was providing the main
stimulus to the legume crop. To achieve this objective inoculated
and uninoculated legumes were grown with and without sulphur and
with and without nitrogen fertilizer. At a suitable stage of
growth yield data, and total nitrogen content of the plants and
of the medium in which they were grown, were determined.