Four of the nine phosphate-solubilizing isolate isolates(#9,12,
19 and 24) and the non-phosphate-solubilizing isolate (# 5)
failed to colonize the roots in the root colonization plate assay
8 days after emergence. Actinomadura sp. (isolate # 14), M.
endolithica (isolate # 18) and Actinoplanes sp. (isolate # 21)
colonized 95% of roots by 6 days after radicle emergence,
whilst Microbispora sp. (isolate # 27) and Streptosporangium sp. (isolate # 30) colonized 85% and 80% of roots 7 days after
radicle emergence, respectively.