Effect of lignite humic acid on soil nutrient availability at different growth stages of rice grown on Vertisols and Alfisols

Abstract

Field experiments were conducted with rice (ADT-39) during the wet Kharif season (July-October 2001) at two locations, the Tamil Nadu Rice Research Institute (TRRI) farm, Aduthurai (Vertisol) and the Agricultural Research Station (ARS) farm, Pattukkottai (Alfisol), representing the old and new delta areas of the Cauvery, respectively. The same set of treatments was followed in both soils. The treatments consisted of the recommended NPK fertilizer application at 75% and 100% alone, and 10 or 20 kg ha -1 humic acid (HA) in combination with NPK fertilizers as soil application, besides an integrated method involving soil application, root dipping and foliar spraying with humic acid and NPK fertilizers. Initial soil samples from the experimental fields were analysed for physical, physico-chemical and chemical properties. Surface soil samples were collected at critical growth stages and analysed for various available nutrients. The results of the field experiments revealed that the application of humic acid along with inorganic fertilizers led to higher soil nutrient availability at all the growth stages of rice. Similar results were obtained in both Vertisol and Alfisol. The present investigation concluded that the best treatment for soil nutrient availability was 10 kg ha -1 HA (soil application) + 0.1% HA foliar spray (twice) + 0.3% HA root dipping + 100% NPK, which was on par with the treatment involving 20 kg ha -1 HA (soil application) + 100% NPK compared to the other treatments.

A bioassay of long‐term stockpiled salvaged soil amended with biochar, peat, and humalite

“…Humalite and peat, on the other hand, had much lower pH values thereby reducing the pH of the amended soils. These findings corroborate those from previous studies (Nandakumar, Sarvanan, Sigaram, & Chandrasekaran, 2004;Sanli et al, 2012). As expected, the blended amendments, BCH and BCP, produced intermediate pH values.…”

Effect of Potassium Humate Application on Yield and Nutrient Uptake of Maize Grown In a Calcareous Soil

“…Sharif et al, (2002) found substantial increases in shoot and root weight of maize by application of humic materials. Also, Nandakumar et al, (2004) found that application of K-humate in combination with N, P and K chemical fertilizers increased availability of soil nutrient at different growth stages of rice.…”

Response of Chickpea to application of Humic Acid along with Vermicompost on Uptake of Nutrients, Yield attributes and Yield

“…They have reported 8 to 20 per cent increase in wheat yield, 14 per cent in rice yield, 8 per cent in vegetables and 44 per cent in radish yield with application of HA. Nandakumar (2004) observed higher grain yield of rice with humic acid @ 20 kg ha -1 along with 100 per cent NPK and the per cent increase in grain yield over control was 50.41 and 53.84 per cent in clay loam and sandy loam soils, respectively. Balasubramaniam et al, (2000) reported that the yield attributes viz., grain and stover yield of soybean increased significantly with addition of humic acid @ 20 kg ha -1 to soil along with spraying (0.01 %) at flowering stage.…”