English: Steps involved in maintaining pH and ioninc balance during w:Nitrate assimilation. Different plants use different different pathways to different levels. Castor, soya bean and tomato each have different strategies. Tomatoes take in a lot of K+ and accumulate salts in their vacuoles, castor reduces nitrate in the roots to a large extent and excretes the resulting alkali. Soy bean moves a large amount of malate to the roots where it is converted to alkali while the potassium is recirculated.