For a successful pea production on polluted soils, inoculation with beneficial microbes requires active interaction between the microbial components and the plant

摘要

We conducted a pot experiment to study the effect of inoculation with Glomus intraradices isolate BEG141, Rhizobium leguminosarum bv. viciae strain G and Pseudomonas brassicacearum strain Am3 on three genotypes of Pisum sativum L. (VIR3429, VIR4488, VIR8456) grown in the presence of cadmium (Cd) elevated (5.4 mg Cd kg -1 ) and unpolluted (4.8 mu g Cd kg -1 ) soils. Shoot and seed biomass and phosphorus (P) accumulation in seeds were lower in plants grown in the Cd polluted soil, and Cd uptake was higher than in plants grown in the non-polluted soil. There were differences between pea genotypes with respect to their uptake of Cd. Glomus intraradices inoculation increased mycorrhizal colonization of roots only in the polluted soil. Inoculation with R. leguminosarum or P. brassicacearum had no effect on plant growth or mycorrhizal colonization. A positive mycorrhizal effect existed on shoot and seed biomass in genotype VIR3429 grown in the polluted soil and on shoot biomass in genotype VIR4788 grown in the non-polluted soil. The VIR8456 treatment did not induce any response to inoculation with the mycorrhizal fungus in the soils. Seed P concentration increased in the non-polluted soil after inoculation with R. leguminosarum and the mixture of three inocula. Glomus intraradices and P. brassicacearum increased Cd concentration and total Cd in seeds of plants grown in the polluted soil. The results illustrate that 1) the ability of G. intraradices to improve pea growth in Cd polluted soil significantly depends on plant genotype, and 2) optimization of inoculations with beneficial microbes requires active interaction between the microbial components and the plant under specific soil conditions.