Responses of agronomically important crops to inoculation with Azospirillum

Abstract

This paper originates from an address at the 8th International Symposium on Nitrogen Fixation with Non-Legumes, Sydney, NSW, December 2000 Azospirilla are free-living rhizobacteria that are able to promote plant growth and increase yields in many crops of agronomic importance. It is assumed that the bacteria affect plant growth mainly by the production of plant growth promoting substances, which leads to an improvement in root development and an increase in the rate of water and mineral uptake. In the present review, we discuss the physiological responses of the plant roots to inoculation with Azospirillum, and report on field and greenhouse experiments carried out with these bacteria during 1994–2001 in Belgium, Uruguay, Mexico and Israel.

Potential ofPseudomonasandBacillusIsolates as Biocontrol Agents Against Fusarium Wilt of Eggplant

“…Exactly how a beneficial bacterium induces changes in plant root morphology and colonization is not yet clearly understood. Bacterial population of hormonelike substances and their ability to stimulate endogenous hormone levels were believed to play an important role in this process (12). however, recently nitric oxide, diffusible gas, has been shown to act as a signaling molecule in an iAAinduced pathway involved in adventitious root development (28).…”

Inoculation with selected strains of Azospirillum brasilense and A. lipoferum improves yields of maize and wheat in Brazil

“…The bacteria are believed to produce various phytohormones that improve root growth and absorption of water and minerals and increase tolerance of stresses such as salinity and drought, leading to more-vigorous and more productive plants (e.g. Bashan and Holguin 1997;Dobbelaere et al 2001;Bashan et al 2004). In addition, Azospirillum fixes atmospheric nitrogen associatively with several non-leguminous species (e.g.…”

Inoculation with Azospirillum brasilense Improves Nutrition and Increases Wheat Yield in Association with Nitrogen Fertilization

“…Increases in water and mineral uptake have been reported, as well as greater tolerance to stresses, such as salinity and drought, resulting in a more vigorous and productive plant [17,18]. According to Dobbelaere et al [19], positive responses to inoculation with A. brasilense are obtained even when the crops are grown in soils with high N content available, which indicates that the plant responses occur not only due to the N 2 ixed but also mainly depending on the production of phytohormone growth promoters such as cytokinin, gibberellin, and indoleacetic acid.…”