Nitrate Uptake by Manganese‐Deficient Lemon Plants

Abstract

AbstractThe uptake of nitrate and water was followed in Eureka lemon (Citrus limon (L.) Burm. f.) plants grown in solution culture in a greenhouse under short (3–6 months) and long‐term (22–24 months) Mn‐nutrition stress. Uptake was determined from depletion in the nutrient solution.Under short‐term stress, manganese‐deficient plants absorbed 14.5% more nitrate and 3.4% more water than the control plants, on a weight basis. Under long‐term stress there was a three‐fold increase in nitrate and a two‐fold increase in water uptake in the Mn‐deficient plants.The intensive nitrate uptake under Mn‐deficiency stress was more spectacularly demonstrated in plants which were exposed also to low nitrogen supply. The low‐nitrogen Mn‐deficient plants absorbed more nitrate, had less stunted growth and developed fewer visible symptoms of both N and Mn deficiencies than high‐nitrogen Mn‐deficient plants.