ISSN:
1573-5036
Keywords:
Arthrobacter
;
Blue grama
;
Bouteloua gracilis
;
Herbage removal
;
Pseudomonas
;
Rhizoplane
;
Rhizosphere
;
Soil
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Summary Streptomycin-resistant Pseudomonas and Arthrobacter were isolated from semi-arid grassland soil and their relative responses in the rhizosphere of blue grama (Bouteloua gracilis) subjected to herbage removal were evaluated. Using plants grown in normal soil, the two bacteria showed differential responses to herbage removal, which were most marked in the rhizoplane, where the Pseudomonas showed a two-log unit increase over a 60 hour period, while Arthrobacter, in contrast, exhibited a one-log unit decrease in viable counts for at least 48 hours after defoliation, responses which are similar to those observed in root exudate medium experiments by earlier workers. These results suggest that the rhizoplane may be a critical environment for interaction of these two types of microorganisms, and that sequential responses of the root-associated soil microorganisms may occur after herbage removal from this important rangeland plant. These responses are most likely associated with increased exudate release following herbage removal, which has been best documented using blue grama grown under sterile conditions.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02205028
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