Effect of humic acid multinutrient complex fertilizers on yield and quality of tomato and potato

Field experiment was conducted in the farm of Indian Agricultural Research Institute, New Delhi during winter season, 2009–10 to study the effect of different humic acid complex fertilizers and conventional chemical fertilizers on yield and quality of tomato and potato. Application of Grow Flow 45H (Humic acid multinutrient liquid fertilizer) at recommended dose significantly increased tomato and potato yields. Increase in potato yield was 9.3% as compared to chemical fertilizer and 88.2% as compared to control. In tomato also 7.7%, 4.0% and 48% increase in yield due to application of Grow Flow 45H over chemical fertilizer alone, chemical fertilizer plus Supa humus and control. The highest leaf chlorophyll contents of 2.9 mg g1 and 1.99 mg g−1for tomatoandpotatoleaveswerefound in GrowFlow45H treated plants followed byHA-NPKcomplex fertilizers. The quality parameters for tomato such as skin colour, lycopene content, acidity and pH of fruit juice, ascorbic acid and total soluble solids and potato such as specific gravity, starch, total and reducing sugars were significantly influenced by the application of Grow Flow 45H. Though HA-NPK fertilizer developed in the laboratory was not significantly differed with chemical fertilizer in respect to yield and quality of tomato and potato; however the former was found better than the latter.