Rhizobium sp. – a Potential Tool for Improving Protein Content in Peas and Faba Beans

Abstract

Abstract. Legume seed inoculation prior to sowing is a well-known practice in agriculture. Nitrogen fixation, due to the symbiotic relationship between legumes and rhizobia, improves the productivity of legumes. Rhizobia strain specificity can be observed very often, leading to differences in the total protein content. In this study two faba bean cultivars ('Karmazyn' and 'Bartek') and five pea cultivars ('Retrija', 'Zaiga', 'Lāsma', 'Vitra' and 'Bartek') were tested using various rhizobia strains. In addition, strain effectivity was observed in four different soil types. Overall, the protein content increase was observed after seed inoculation with Rhizobium sp. Rhizobia strain and plant cultivar interaction specification was observed. Plant cultivar appeared to have a decisive role in the formation of protein content when inoculated with Rhizobium sp. From these pilot experiments, it can be concluded that, when choosing Rhizobium sp. strains for legume inoculation, soil type also should be considered. Rhizobia has the potential to be used as a commercial preparation intended for increasing legume protein content, alongside with increased legume yield; however, different rhizobia strains should be mixed together to achieve the optimal result.

Faba Bean: An Untapped Source of Quality Plant Proteins and Bioactives

“…Faba bean varieties are therefore highly heterogeneous in size (less than 0.3 g to more than 1 g per seed) [71], color, and shape [80,81], depending on the cultivating area and the environmental conditions during the cropping year [82]. Soil composition, atmospheric nitrogen fixation efficiency, and environmental stress, such as drought, are all factors that can affect faba bean protein content [83,84]. Hood-Niefer, Warkentin, Chibbar, Vandenberg, and Tyler [42] have demonstrated that the protein content of 11 faba bean varieties grown in three western Canadian regions during two different years (2006 and 2007) fluctuated from 27.5 to 32.4%.…”