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

Abstract

MS received 21 November 1978; revised 12 February 1980 Abstract. Nitrogen, phosphorus and potassium deficiency reduced the uptake of 32 P- phosphate, 35 S-sulphate, 24 Na-, 42 K-, 45 Ca-, M Mn-, 59 Fe- and 65 Zn- 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 32 P-phosphate uptake was more severe with nitrogen deficient plants than that in phosphate deficient ones; potassium deficient plants, however, took up 42 K- as avidly as the control plants. Simultaneously the uptake of 35 SO4 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 radio- nucleides taken up accumulated in the young regions as in the case of pea and other dicotyle- donous plants. Mobilization of 32 P and 35 S in the reproductive plants was most markedly