DIFFERENTIAL RESPONSE OF GROUNDNUT GENOTYPES TO IRON-DEFICIENCY STRESS

Differential response of groundnut genotypes to iron-deficiency stress was studied in soils containing high calcium carbonate. Genotypes differed significantly for some traits that appeared to be important in determining adaptation to low iron. The genotypes TCGS 273, TCGS 2, TCGS 37, and Kadiri 3 bad higher total chlorophyll, total dry matter, and active iron (Fe2+) contents under iron-deficiency stress conditions. Total chlorophyll followed by active iron were found to be sensitive parameters to Fe deficiency. Based on the visual deficiency symptoms (chlorosis score), the genotypes were classified into three groups. Efficient (no genotype was found efficient), moderately efficient (TCGS 273, TCGS 2, TCGS 3, and Kadiri 3), and inefficient (TCGS 1, TCGS 7, TCGS 11, TCGS 26, TCGS 28, TCGS 29, TCGS 30, TCGS 1518, TPT 1, TPT 2, ICGS 11, ICGS 44, Girnar, JL 24, ICGS(E) 21, and TMV 2).