Root and Root Hair Growth in Relation to Calcium Supply and Mobility

The study on oat seedlings demonstrated that root hair elongation was greatest in moist air, despite lower calcium content compared to complete nutrient solutions. It suggested that minimal calcium might suffice for root hair growth if roots are not exposed to toxic ionic environments. Calcium-deficient solutions led to deformed and suppressed root hair elongation, likely due to ion toxicity rather than calcium deficiency. Experiments with 45Ca confirmed that calcium from seeds was transported to roots and used in hair elongation, but calcium absorbed by one root was not transferred to another within the same seedling.