Summary: Migration of the rhizosphere bacteria Azospirillum brasilense and Pseudomonas Puorescens towards wheat seedlings grown in soil was studied under various environmental conditions. The main factor affecting motility was soil moisture; of secondary importance were the soil type and the duration of plant growth prior to bacterial application. Migration was initiated following a lag of 24 h and was characterized by a bacterial band migrating through the soil towards the plant roots. Migration was significantly stimulated by various wheat genotypes and by synthetic attractants, though they did not differ in the intensity of their effect. It is proposed that these two rhizosphere bacteria can be stimulated to migrate non-specifically towards growing wheat. plants.
BashanY.1986a; Enhancement of wheat root colonization and plant development by Azospirillum brasilense Cd. following temporary depression of the rhizosphere microflora. Applied and Environmental Microbiology 51:1067–1071
BashanY.1986b; Alginate beads as synthetic inoculant carriers for the slow release of bacteria that affect plant growth. Applied and Environmental Microbiology 51:1089–1098
BashanY.,
LevanonyH.1985; An improved selection technique and medium for the isolation and enumeration of Azospirillum brasilense
. Canadian Journal of Microbiology 31:947–952
BennettR. A.,
LynchJ. M.1981b; Bacterial growth and development in the rhizosphere of gnotobiotic cereal plants. Journal of General Microbiology 125:95–102
BowenG. D.1979; Integrated and experimental approaches to the study of growth of organisms around roots. In Soil-borne Plant Pathogens pp 209–227 Edited by
SchippersB.,
GamesW.
London: Academic Press;
BrockwellJ.,
WhalleyR. D. B.1970; Studies on seed pelleting as an aid to legume seed inoculation. 2. Survival of Rhizobium meiiloti applied to medic seed sown into dry soil Australian Journal of Experimental Agriculture and Animal Husbandry 10:455–459
BrockwellJ.,
BryantW. G.,
GaultR. R.1972; Ecological studies of root-nodule bacteria introduced into field environments. 3. Persistence of Rhizobium trifolii in association with white clover at high elevations Australian Journal of Experimental Agriculture and Animal Husbandry 12:407–413
ChetI.,
ZilbersteinY.,
HenisY.1973; Chemotaxis of Pseudomonas lachrymans to plant extracts and to water droplets collected from leaf surfaces of resistant and susceptible plants. Physiological Plant Pathology 3:473–479
FosterR. C.,
BowenG. D.1982; Plant surfaces and bacterial growth: the rhizosphere and the rhizoplane. In Phytopathogenic Prokaryotes pp 159–185 Edited by
MountM. S.,
LacyG. H.
London: Academic Press;
HamdiY. A.1974; Vertical movement of rhizobia in soil. Zentralblatt fur Bakteriologie, Parasitenkunde, Infektionskrunkheiten und Hygiene, Abteilung Originate 129:373–377
HarrisR. F.1981; Effect of water potential on microbial growth and activity. In Water Potential Relations in Soil Microbiology pp 23–96 Madison, Wisconsin: Soil Science Society of America;
HeinrichD.,
HessD.1985; Chemotactic attraction of Azospirillum lipoferum by wheat roots and characterization of some attractants. Canadian Journal of Microbiology 31:26–31
HeulinT.,
BallyR.,
BalandreauJ.1982; Isolation of very efficient N2-fixing bacteria from the rhizosphere of rice. In Azospirillum Experientia Supplementum 4292–99 Edited by
KlingmüllerW.
Basel: Birkhäuser Verlag;
HeulinT.,
WeinhardP.,
BalandreauJ.1983; Motility changes in Azospirillum lipoferum
. In Azospirillum II Experientia Supplementum4889–94 Edited by
KlingmüllerW.
Basel: Birkhäuser Verlag;
LevanonyH.,
BashanY.,
KahanaZ. E.1985; Enzyme-linked immunosorbent assay for the identification and enumeration of Azospirillum brasilense Cd. FEMS Symposium on Microbial Communities in Soil, Copenhagen, Denmark pp 77–77
LynchJ. M.1981; The rhizosphere. In Experimental Microbial Ecology pp 1–23 Edited by
BurnsR. G.,
SlaterJ. H.
Oxford: Blackwell Scientific Publications;
RobsonA. D.,
LoneraganJ. F.1970; Nodulation and growth of Medicago truncatula on acid soils. II. Colonization of acid soils by Rhizobium meiiloti.Australian Journal of Agricultural Research 21:435–445
RoviraA D.,
BowenG. D.,
FosterR. C.1983; The significance of rhizosphere microflora and mycorhizas in plant nutrition. In Encyclopedia of Plant Physiology New Series, vol 15A pp 61–93 Edited by
LauchliA.,
BieleskiR. L.
Berlin: Springer Verlag;
SuslowT. V.1982; Role of root colonizing bacteria in plant growth. In Phytopathogenic Prokaryotes pp 187–223 Edited by
MountM. S.,
LacyG. H.
London: Academic Press;
TarrandJ. J.,
KriegN. R.,
DöbereinerJ.1978; A taxonomic study of the Spirillum lipoferum group, with descriptions of a new genus, Azospirillum gen. nov. and Azospirillum brasilense sp. nov. Canadian Journal of Microbiology 24:967–980
ThorntonH. G.,
GanguleeB. A.1926; The life cycle of the nodule organism Bacillus radicicola in soil and its relation to the infection of the host plant. Proceedings of the Royal Society B99:427–451
WallaceH. R.1978; Dispersal in time and space: soil pathogens. In Plant Disease: an Advanced Treatise vol 2 pp 181–202 Edited by
HorsfallJ. G.,
CowlingE. B.
New York: Academic Press;