Field screening accessions of Phaseolus vulgaris for capacity to nodulate over a range of environments

Abstract

Nineteen lines of Phaseolus vulgaris L. were identified as promising for nodulation ability in a sequence of 2 screenings from 1462 germplasm accessions. These 19 lines plus 4 checks were further evaluated over 4 sites (Rocklea in 1985; Hermitage, Kingaroy and Applethorpe in 1987) and were sown within split-blocks with main treatments of nitrogen fertiliser, inoculum applied, and control with nodulation dependent on indigenous rhizobia. Nitrogen fertiliser significantly suppressed nodulation at Applethorpe and Hermitage sites only. Inoculation with Rhizohium phuseoli strain CC511 was most effective at Applethorpe, the least fertile site. The control nodulated most at Kingaroy. Accession ICA2 1573 was exceptional in its ability to nodulate with indigenous or supplied inoculum, and in the presence of nitrogen fertiliser. This nodulating ability was also shown, less consistently, by accessions Epicure and Amarillo 155. Some accessions were treatment specific for nodulation level: the superior nodulation ability of Campbell 20 was strongly inhibited by nitrogen fertiliser; specific cultivar-Rhizobium strain compatibility was shown by Selection 46, Small White 38, and Red Mexican; BAT1 198 and G6637 were apparently incompatible with Rhizobium strain CC511. Other accessions showed site and treatment specific nodulation responses, while the check entry, Gallaroy, was consistently poor in nodulation throughout the trial.