Root nodule structure in Chamaecytisus podolicus

By means of microscopic analyses, it was shown that root nodules formed by Chamaecytisus podolicus exhibited all structural features typical for indeterminate nodules of temperate genistean shrubs: (i) apical nodule meristem composed of infected and non-infected domains, (ii) parenchymatous bacteroid-containing tissue with infected cells only resulting from mitotic activity of infected meristematic cells, (iii) absence of infection threads, and (iv) convoluted bacteroids singly enclosed in a symbiosome membrane. For the first time, it was shown that the nodule meristem is organized into longitudinal files of sister cells