[Effects of soil factors on root colonization of wheat by luxAB genes-marked Pseudomonas fluorescens Xl6L2]

Abstract

Colonization density of Pseudomonas fluorescens Xl6L2 marked with luxAB genes in wheat Rhizosphere in sterilized Rhizobox--Calcareous chao soil microcosms was greater than that in insterilized microcosms. The population of Pf.Xl6L2 in the Rhizosphere in the rhizobox--Yellow brown soil microcosms was larger than that in the Calcareous chao soil microcosms; As soil water content was about 50% field capacity (FC), Pf.Xl6L2 could move to the place of 8 cm of root from coated seeds in the former microcosm, but only 4 cm in the later microcosm. In the former microcosms, the number of Pf.Xl612 in the rhizosphere under 60% FC and 75% FC were greater than that under 50% FC; In the second microcosm, the dispersal distance of Pf.Xl6L2 along the root was affected significantly by the soil moisture, it could be detected as far as 8 cm of root from the coated seeds under 60% FC and 75% FC.