Abstract

BECQUER, C.J et al. Selection of rhizobia adapted to livestock production ecosystems from Alberta, Canada, inoculated in corn (Zea mays, L.).: Stage I: greenhouse. Pastos y Forrajes [online]. 2008, vol.31, n.4, pp.1-1. ISSN 0864-0394.

A greenhouse experiment was conducted in order to select rhizobium strains inoculated on corn (Zea mays, L.), for which 16 Canadian native strains of Sinorhizobium meliloti, as well as 12 commercial strains, belonging to different rhizobium genera and species, were used. The inoculi were prepared in BYM medium and shaken to obtain a titer of 10⁶-10⁸ cells/mL.. The variables evaluated were: aerial dry weight (ADW), root dry weight (RDW) and stem length (SL). In all the variables some inoculated treatments were observed to be statistically higher than the absolute control. In ADW two treatments did not differ significantly from the fertilized control; while only four inoculated treatments in SL and five in RDW were statistically lower than the fertilized control. Cluster analysis allowed to select the strains CAC8, CAC9, CAC17 and CAC17a, for their later evaluation under field conditions. One hundred percent of the treatments selected in the dendrogram were inoculated with native strains. When evaluating the treatments regarding the level of dependence of ADW and SL with regards to RDW, a strong regression of ADW was observed in the ones inoculated with native strains, and a weak regression in the treatments inoculated with commercial strains. The regression was weak in SL for all treatments. To continue this research under field conditions, in addition to further studies, is recommended.

Keywords : Inoculation; Rhizobium; Sinorhizobium; Zea mays.