Symbiosis

Publication date: 2005-01-01
Volume: 38 Pages: 87 - 98
Publisher: Balaban Publishers

Author:

Nápoles, M
Luyten, Ellen ; Dombrecht, B ; Laeremans, A ; Vanderleyden, Jozef ; Costales, D ; Gutiérrez, A ; Corbera, J

Keywords:

av-SPI, Science & Technology, Life Sciences & Biomedicine, Microbiology, molasse, soybean cake, genistein, inoculant, NOD FACTORS, NODULATION, GENISTEIN, JAPONICUM, IDENTIFICATION, INHIBITION, EXPRESSION, FIXATION, GENES, SOIL, 0605 Microbiology, 1108 Medical Microbiology, Plant Biology & Botany, 3107 Microbiology

Abstract:

The biosynthesis of Nod factors is specific to rhizobial species and is induced by appropriate signals, mostly flavonoids, excreted by the host plant. Nod factors from numerous different strains have been characterized and the molecular and biochemical mechanisms of Nod factor production have been elucidated in detail. Here, we report the influence of different culture media on Nod factor biosynthesis and symbiotic efficiency of two strains of Bradyrhizobium elkanii. The different growth media were validated by using them to grow the inoculants for soybean on two different field sites in Habana Province, Cuba. The effect on nodulation parameters and soybean yield was evaluated. Depending on the culture medium used to grow the inoculant, the number of nodules obtained per plant and the corresponding nitrogen fixation activity differed. Consequently, the results under field conditions showed different soybean yield, depending on the media used. In addition, thin-layer chromatography analysis revealed that different mixtures of Nod factors were produced when different media were used.