In:
Canadian Journal of Microbiology, Canadian Science Publishing, Vol. 46, No. 3 ( 2000-03-01), p. 229-236
Abstract:
A plant growth-promoting rhizobacterium belonging to the genus Achromobacter was isolated from the oilseed-rape (Brassica napus) root. Growth promotion bioassays were performed with oilseed rape seedlings in a growth chamber in test tubes containing attapulgite and mineral nutrient solution, containing NO 3 - as N source. The presence of this Achromobacter strain increased shoot and root dry weight by 22-33% and 6-21%, respectively. Inoculation of young seedlings with the Achromobacter bacteria induced a 100% improvement in NO 3 - uptake by the whole root system. Observations on the seminal root of seedlings 20 h after inoculation showed that there was an enhancement of both the number and the length of root hairs, compared to non-inoculated seedlings. Electrophysiological measurements of NO 3 - net flux with ion-selective microelectrodes showed that inoculation resulted in a specific increase of net nitrate flux in a root zone morphologically similar in inoculated and non-inoculated plants. The root area increased due to root hair stimulation by the Achromobacter bacteria, which might have contributed to the improvement of NO 3 - uptake by the whole root system, together with the enhancement of specific NO 3 - uptake rate. Moreover, inoculated plants showed increased potassium net influx and proton net efflux. Overall, the data presented suggest that the inoculation of oilseed-rape with the bacteria Achromobacter affects the mineral uptake.Key words: Brassica napus, plant growth-promoting rhizobacteria, Achromobacter sp., mineral uptake, root morphology.
Type of Medium:
Online Resource
ISSN:
0008-4166
,
1480-3275
Language:
English
Publisher:
Canadian Science Publishing
Publication Date:
2000
detail.hit.zdb_id:
280534-0
detail.hit.zdb_id:
1481972-7
SSG:
12
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