Boron deficiency affects ATP hydrolysis of plasma membrane and nutrients uptake in coffee: Consequences for plant growth

Abstract

Boron (B) shapes the plasma membrane structure and modulates the plasma membrane H+-ATPase activity stimulating nutrients uptake by the plant root system. However, the influence of B-nutritional status on plasma membrane H+-ATPase activity of some plants remains unclear, especially in dicots with higher B requirement, such as coffee. This study investigated the effects of B-nutritional status on ATP hydrolysis of plasma membrane and nutrients uptake in coffee. Coffee seedlings were grown in substrate with six B levels (0.1, 0.2, 0.4, 0.6, 0.8 and 1.0 mg dm−3, as H3BO3) for 153 days and plasma membrane H+-ATPase activity was evaluated in the roots, as well as nutrient concentration and accumulation in leaf tissues and plant growth. The B nutritional status greatly influenced plasma membrane H+-ATPase activity in roots. At 1.0 mg dm−3, the ATPase hydrolysis activity was six times greater and H+ transport two times higher compared to the lowest level of 0.1 mg dm−3. The B supply increased significantly leaf concentrations of B, K, P, Mg, and Ca; nevertheless, accumulation of these nutrients did not vary in the leaves because leaf biomass decreased at high B levels.