Effects of nitrogen source and water availability on stem carbohydrates and cellulosic bioethanol traits of alfalfa plants
Keywords: 
Cell wall
Soluble carbohydrates
Drought
Nitrogen fixation
Medicago sativa L.
Issue Date: 
May-2012
Publisher: 
Elsevier
Citation: 
Fiasconaro ML, Gogorcena Y, Muñoz F, Andueza D, Sanchez-Diaz M, Antolin MC. Effects of nitrogen source and water availability on stem carbohydrates and cellulosic bioethanol traits of alfalfa plants. Plant Sci 2012 Aug;191-192:16-23.
Abstract
Symbiotic association of legumes with rhizobia frequently results in higher photosynthesis and soluble carbohydrates in comparison with nitrate-fed plants, which might improve its potential for biomass conversion into bioethanol. A greenhouse experiment was conducted to examine the effects of nitrogen source and water availability on stem characteristics and on relationships between carbohydrates, phenolic metabolism activity and cell wall composition in alfalfa (Medicago sativa L. cv. Aragón). The experiment included three treatments: (1) plants fed with ammonium nitrate (AN); (2) plants inoculated with rhizobia (R); and (3) plants inoculated with rhizobia and amended with sewage sludge (RS). Two levels of irrigation were imposed: (1) well-watered and (2) drought stress. Under well-watered conditions, nitrogen-fixing plants have increased photosynthesis and stem fermentable carbohydrate concentrations, which result in higher potential for biomass conversion to bioethanol than in AN plants. The latter had higher lignin due to enhanced activities of phenolic metabolism-related enzymes. Under drought conditions, the potential for bioethanol conversion decreased to a similar level in all treatments. Drought-stressed nitrogen-fixing plants have high concentrations of fermentable carbohydrates and cell wall cellulose, but ammonium nitrate-fed plants produced higher plant and stem biomass, which might compensate the decreasing stem carbohydrates and cellulose concentrations

Files in This Item:
There are no files associated with this item.


Items in Dadun are protected by copyright, with all rights reserved, unless otherwise indicated.