![Nitrogenase activity and trehalose content of nodules of drought-stressed common beans infected with effective (Fix^+) and ineffective (Fix^-) rhizobia [An article from: Soil Biology and Biochemistry]](https://www.ebooknetworking.net/books/B00/0RR/bigB000RR3CCE.jpg)
Nitrogenase activity and trehalose content of nodules of drought-stressed common beans infected with effective (Fix^+) and ineffective (Fix^-) rhizobia [An article from: Soil Biology and Biochemistry]
Description
This digital document is a journal article from Soil Biology and Biochemistry, published by Elsevier in 2004. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.
Description:
Nitrogenase activity and trehalose accumulation were measured in nodulated and non-nodulated common beans (Phaseolus vulgaris) that were exposed to drought. Plants were infected with the Fix^+Rhizobiumsp NGR234, or a Fix^- derivative (NGR@WfixF), or high trehalose-producing, native rhizobia. Trehalose content increased significantly while acetylene reduction activity (ARA) decreased in the nodules of plants exposed to drought. Nevertheless, ARA decreased at a slower rate in nodules with high trehalose levels. Under water stress, nodules infected with NGR@WfixF tended to accumulate more trehalose than nodules infected with wild-type NGR234 (9+/-0.1 vs 8+/-0.1mgg^-^1 dw, respectively). Highest trehalose accumulations were registered in nodules of plants infected with native rhizobia (average 16mgg^-^1 dw), and these plants also exhibited the highest relative water content (65%), while in plants infected with the NGR@WfixF RWC was significantly lower (56%). Our results suggest that nodule trehalose may protect bacterial nitrogenase activity under drought conditions, and that both trehalose and biological nitrogen fixation (BNF) contribute to drought tolerance.
Description:
Nitrogenase activity and trehalose accumulation were measured in nodulated and non-nodulated common beans (Phaseolus vulgaris) that were exposed to drought. Plants were infected with the Fix^+Rhizobiumsp NGR234, or a Fix^- derivative (NGR@WfixF), or high trehalose-producing, native rhizobia. Trehalose content increased significantly while acetylene reduction activity (ARA) decreased in the nodules of plants exposed to drought. Nevertheless, ARA decreased at a slower rate in nodules with high trehalose levels. Under water stress, nodules infected with NGR@WfixF tended to accumulate more trehalose than nodules infected with wild-type NGR234 (9+/-0.1 vs 8+/-0.1mgg^-^1 dw, respectively). Highest trehalose accumulations were registered in nodules of plants infected with native rhizobia (average 16mgg^-^1 dw), and these plants also exhibited the highest relative water content (65%), while in plants infected with the NGR@WfixF RWC was significantly lower (56%). Our results suggest that nodule trehalose may protect bacterial nitrogenase activity under drought conditions, and that both trehalose and biological nitrogen fixation (BNF) contribute to drought tolerance.
