Faba Beans

     Faba beans are legumes that have been cultivated as a green manure crop, human food and stockfeed for many years (reference 1 and 2). Early maturing faba beans are better adapted to cooler, wetter prairie environments and the crop can be cut for grain and forage, making it a good crop choice for some regions of Saskatchewan. The faba bean fixes nitrogen (used as a fertilizer) in the soil and has the potential to offset high nitrogen costs in crop rotations with cereals and canola.

Condensed Tannins

      Secondary metabolites are natural compounds that are restricted to a specific plant species or specific plant organs that participate in interactions between the plant and its environment. Condensed tannin is one of these compounds existing in the seed coat of faba beans that accounts for the seed color. The lower the tannin level in the seed, the better the beans will be for food and animal feed (reference 3). Knowing this, scientists have been trying to develop small-seed faba beans with low tannin levels (pale yellow seed coat). Small seeds are also preferred to larger ones because they have a smaller net weight and are therefore cheaper for seeding. Fingerprinting different lines around the world would show the genetic similarities and differences of faba beans, thus the better lines can then be selected for our needs.

    Condensed tannins are synthesized through two kinds of monomeric precursors: catechin and/or epicatechin, which are produced by two different branches of condensed tannin biosynthesis pathway (Figure 1, reference 4). Chemical analysis of the condensed tannin monomer composition in faba bean seed coat will tell us about which tannin monomer exists in its seed coat, thus providing information for future genetic engineering of the crop.