Analysis of pea (Pisum sativum L.) supernodulating mutants

A comparative analysis of two parental pea cultivars, Rondo and Ramonskii 77; two supernodulating mutants, nod(3) and nod(4); and the Torsdag line with a marker Nod(5) gene was conducted. The mutants had more than 1000 nodules per plant, which were small and evenly distributed along the root system. In the Torsdag line, the number of nodules was smaller (200-230 nodules per plant), but they were larger and were Located in the upper part of the roots. By crossing the Torsdag line with supernudulating mutants, forms with two types of nodules were isolated: very small, as in mutants, and large, as in the Torsdag line. It is concluded that two regulatory systems controlling nodulation may operate simultaneously in one plant.