  In this paper we present the first results of a radio survey at 22 cm in the
central region of the Shapley Concentration, carried out with the Australia
Telescope Compact Array. In order to study the effect of merging on the
statistical properties of radio galaxies, and the relation between merging and
the existence of {\it relic} and {\it halo} type radio sources, we observed the
two complexes of merging clusters centered on A3528 and on A3558. Our results
show that the radio source counts in these regions, characterised by very high
optical overdensity and major cluster mergers, do not differ from the
background source counts. This suggests that the merging phenomenon does not
influence the probability of a galaxy to become radio surce. Furthermore we
investigated the possibility that the extended radio source J1324-3138 is a
relic, applying the model recently proposed by Ensslin et al. (1998). Our
analysis shows that the properties of J1324-3138 are consistent with the idea
that the source is a relic located on the shock front between A3556 and a
smaller group accreting onto the main cluster concentration.
