The effect of root-knot nematode, Meloidogyne javanica and the reniform
nematode, Rotylenchulus reniformis alone on nodulation of four Rhizobium species
on roots of 27 cultivars related to six leguminous species were evaluated. The
formation of nodules on their roots varied greatly in their numbers according to host
species, host cultivars, rhizobal species and nematode species. The greater
nodulation reduction in infected roots with nematode species, M. javanica and R.
reniformis was observed on roots of common bean cvs. Exira, Nebraska, Polista
and Savana inoculated with rhizobial species Rhizobium phaseoli and lupine cv.
Giza 2 inoculated with rhizobial species R. lupine. In general, inoculation of M.
javanica or R. reniformis with rhizobial species greatly reduced root nodulation as
compared to leguminous species inoculated with Rhizobium species alone. Also, it
is important to note that the reduction in the number of bacterial nodules was more
pronounced with R. reniformis infection than with M. javanica infection. It is
noteworthy that the number of nodules on roots of broad bean cv. Wade 1
inoculated with R. phaseoli increased by both nematode species infections.