Chlorophyll Content in Leaves of Wheat as Influenced by Inorganic, Organic and Integrated Sources of Nutrient Application

Field experiments were conducted during winter season of 2018-19 and 2019-20 with three sources of nutrient viz., inorganic, organics (FYM, VC and biofertilizers) and their integration as main treatments and five levels [S1-0 (0-0-0 kg NPK ha-1), S2-100% (120-60-40 kg NPK ha-1), S3-150% (180-90-60 kg NPK ha-1), S4-200% (240-120-80 kg NPK ha-1) and S5-Soil Test based (STV) NPK i.e. 149-176-33 kg ha-1 in split plot design with three replications. The chlorophyll content (‘a’, ‘b’ and total) in leaves and Soil Plant Analyzer Development (SPAD) value were recorded at crown root initiation (CRI), tillering, jointing and milking stage of wheat. The pooled data of findings revealed that the treatment with inorganic sources showed significant increase in the SPAD readings (9.62, 15.54, 23.77 and 29.83), chlorophyll ‘a’ (0.76, 0.83, 1.47 and 0.63 mg g-1 leaf tissue), ‘b’ (0.44, 0.78, 0.87 and 0.57 mg g-1 leaf tissue) and total (1.19, 1.64, 2.25 and 1.14 mg g-1 leaf tissue) chlorophyll content in leaves over organic source at all the growth stages.

All the levels of nutrient were significantly increased the chlorophyll content and SPAD value over control at all the stages except chlorophyll ‘a’ at jointing and milking stage. However, amongst the levels 150% and 200% NPK were found significantly superior to 100% NPK for SPAD value (8.32 and 8.71 at CRI and 12.56 and 12.19 at tillering), chlorophyll ‘a’ (0.73 and 0.70 mg g-1 leaf tissue at CRI), chlorophyll ‘b’ (0.46 and 0.45 mg g-1 leaf tissue at CRI, 0.68 and 0.71 mg g-1 leaf tissue at tillering and 0.53 and 0.59 mg g-1 leaf tissue at milking), respectively.

The interaction results suggested that the 200% NPK with inorganic and integrated sources significantly superior to 100% NPK for chlorophyll ‘a’ content at jointing and milking stage. The application of 150% and 200% NPK with inorganic source were found significantly higher over the same level of NPK with integrated source of nutrient for total chlorophyll content and SPAD value at all the growth stages except 150% NPK for total chlorophyll at jointing and milking stage and SPAD value at milking stage. The correlation between SPAD value and chlorophyll ’a’, ‘b’, total were found significantly and positively at all growth stages. Coefficient of determination values between SPAD and chlorophyll content showed linear relationship at all the growth stages.