Direct and Residual Effect of Lignite Humic Acid (Potassium Humate) on Productivity in Turmeric – Maize Cropping System in Alfisol.
Kolappan Baskar, TNAU, 40, Subam colony,, KTC nagar North,, Tirunelveli, Tamil Nadu, South India, India
The potassium humate used in the present study contained 31.8 per cent of HA, the pH of which was 6.96 indicating its neutral reactions. The present investigation ( was carried out to evaluate the impact of HA (applied as 0.1 % foliar, 0.1 % rhizome dipping, 10, 20, 30 and 40 kg ha-1as soil, 10 kg ha-1soil plus either foliar or foliar plus rhizome dipping and no HA control) and NPK fertilization (0, 75 and 100 %) on soil fertility and productivity in Turmeric - Maize system. The highest yield of 28.1 t ha-1 of fresh rhizome was associated with the combined application of 100% NPK plus HA (10 kg ha-1as soil together with foliar spray and rhizome dipping each at 0.1% concentration i.e. M2S9. The yield recorded by M2S9 was comparable with that observed with application of 100 % NPK plus 10 kg HA ha-1 as soil application and 0.1% as foliar spray (M2S8) and 100 % NPK plus 20 kg HA ha-1(M2S5) which recorded 27.8 and 27.5 t ha-1 respectively. The contents of curcumin and oleoresin of turmeric increased with the application of HA- NPK fertilization. Significant improvement in respect of the uptake of N, P, K and S by shoot and rhizome at 90, 180 DAS and at harvest and the uptake of Zn, Fe, Mn and Cu at harvest was observed with the M2S9, M2S8 and M2S5 combinations in turmeric. In maize, the recommended fertilizers and 20 kg ha-1 of HA applied to direct crop of turmeric favorably increased the highest grain and straw yields of 5830 and 11590 kg ha-1 respectively in Alfisol.