NODULATION AND GROWTH OF COMMON BEAN (PHASEOLUS-VULGARIS L) CULTIVARS IN HYDROPONIC CULTURE AND IN THE FIELD

Hydroponic culture of four common bean (Phaseolus vulgaris L.) cultivars was assessed as a means of selecting cultivars on the basis of their capacity to fix N in symbiosis with rhizobium. Two segregants of cultivar CC 25-9 with different seed colours were included. Bean growth in hydroponic cultivation was comparable to that in the field but nodulation was higher in the greenhouse than in the field. A strain-cultivar interaction on nodulation was significant in cultivar CC 25-9, in which some plant factor, possibly related to seed colour, limited nodulation since black-seeded beans nodulated significantly less with Rhizobium leguminosarum by phaseoli CF1 than segregants having red or white seeds. Another strain-cultivar interaction affected nodule function since BAT 482 had a significantly lower specific nodule activity than other cultivars in symbiosis with strain CF1.