Pakistan Journal of Biological Sciences1028-88801812-5735Asian Network for Scientific Information10.3923/pjbs.2000.1556.1559AsgharHafiz Naeem ZahirZahir Ahmad KhaliqAbdul ArshadMuhammad 102000310Rhizobacteria were isolated from rhizosphere of different varieties of rapeseed (Canola, Raya, Toria, Gobi Sarsoon and Sarsoon) selected from different sites of Punjab. These rhizobacteria were tested for auxin production in terms of indoleacetic acid equivalents by colorimeter method both in the presence and absence of an auxin precursor L-tryptophan (L-TRP). This study suggested that auxin production ability varied with variety and site ranging from 0.13 to 11.4 μg mL1 without L-TRP and from 2.41 to 24.6 μg mL1 with L-TRP. L-Tryptophan application increased the auxin production upto 184 fold compared with that produced without L-TRP. The significance of auxin production by rhizobacteria is discussed in relation to their effects on plant growth.]]>Arshad, M. and W.T. Frankenberger Jr.,19931993pp: 307-347pp: 307-347Arshad, M. and W.T. Frankenberger,1990Zea mays and Lycopersicon esculentum to the ethylene precursors, L-methionine and L-ethionine applied to soil.]]>122219227Arshad, M. and W.T. Frankenberger Jr.,199113318Arshad, M. and W.T. Frankenberger Jr.,19976245151Davies, P.J.,1987Pages: 681Pages: 681Frankenberger, Jr. W.T., A.C. Chang and M. Arshad,1990Raphanus sativus to the auxin precursor, L-tryptophan applied to soil.]]>129235241Frankenberger, Jr. W.T. and M. Arshad,1995Pages: 503Pages: 503Hussain, A., M. Arshad, A. Hussain and E. Hussain,1987Zea mays) to Azotobacter inoculation under fertilized and unfertilized conditions.]]>47377Mordukhova, E.A., N.P. Skvortsova, V.V. Kochetkov, A.N. Dubeikovskii and A.M. Boronin,1991Pseudomonas.]]>60345349Nickell, L.G., 1982pp: 173.pp: 173.Rossi, W., A. Grappelli and W. Pietrosanti,198429325329Sarwar, M., M. Arshad, D.A. Martens and W.T. Frankenberger Jr.,1992147207215Wollum, A.G.,19821982pp: 781-802pp: 781-802Zahir, Z.A., S.A. Abbas, M. Khalid and M. Arshad,20003289291