Effect of rhizobia inoc[u]lation on nodulation and yield of the legumes common vetch (Vicia Sativa) and fava bean (Vi[c]ia fa[b]a minor)

Abstract

This dissertation investigates into the effect of Rhizobium inoculation on nodulation, growth and yield on two leguminous species – common vetch (Vicia sativa) and fava bean (Vicia faba minor) – under field conditions at the American Farm School in Thessaloniki, Greece. The study compares three treatments: control (organic fertilization only), PGPR (plant growth-promoting rhizobacteria) and Rhizobium inoculation; the objective being that of evaluating their response on the critical physiological and agronomical traits. The experimental design was 18 plots (9 in each crop) arranged in a randomized complete block set up. The chicken manure was applied on all the plots and inoculants were applied through foliar sprays on vegetative growth stages. The data on the chlorophyll content (SPAD index), root nodulation, plant height, biomass, root weight were measured. Based on results, clearly, Rhizobium inoculation greatly improved the performance of plants of both species. Rhizobium treated plants showed maximum SPAD readings, highest number of root nodules and maximum shoot as well as root biomass. Fava bean was very receptive to inoculation whereas the PGPR treatments had unimpressive effects when used singly. These conclusions show the potential agronomic benefits of Rhizobium for enhancing the rate of biological nitrogen fixation, especially in nitrogenous fertilizer reduction oriented agroecosystems. Microbial inoculants ought to be incorporated into the sustainable and organic agriculture, particularly in the Mediterranean context, according to the research. Additional studies should be conducted regarding the co-inoculation strategies and the long-term health impacts on soil.