Effect of nitrogen, phosphorus and potassium deficiency on the uptake and mobilization of ions in Bengal gram (Cicer arietinum).

ABSTRACT

Nitrogen, phosphorus and potassium deficiency reduced the uptake of 32Pphosphate, 35S-sulphate, 24Na-, 42K-, 45Ca-, MMn-, 59Fe- and 65Zn- by Cicer arietinum (Bengal gram) cv B-75. Root length, leaf area and dry weight of the tissues were also reduced. Since in several cases, the total contents of the radio nucleides both on per plant and per unit dry weight basis were curtailed, the decrease in uptake of several ions cannot be entirely due to reduced growth rate. The reduction in 32P-phosphate uptake was more severe with nitrogen deficient plants than that in phosphate deficient ones; potassium deficient plants, however, took up 42K- as avidly as the control plants. Simultaneously the uptake of 35SO4 2 – and other cations was affected particularly by nitrogen deficiency. The distribution of radionuclides between the root and shoot portions was also disturbed in several cases by deficiency conditions. The radionucleides taken up accumulated in the young regions as in the case of pea and other dicotyledonous plants. Mobilization of 32P and 35S in the reproductive plants was most markedly affected by nitrogen and potassium-deficiency.