Improving rhizospheric environment and sugarcane ratoon yield through bioagents amended farm yard manure in udic ustochrept soil

A field experiment was conducted for two crop cycles during 2003–2005 and 2004–2006 at the Indian Institute of Sugarcane Research, Lucknow in subtropical India. Trichoderma viride and Gluconacetobacter diazotrophicus amended farm yard manure (FYM) increased organic carbon (19.44 Mg ha−1) and available nitrogen (260 kg N ha−1) content of soil from 14.78 Mg ha−1 (OC) and 204 kg N ha−1 observed under farmer's practice (sole N application). Application of bioagents amended FYM improved soil porosity and reduced compaction (bulk density—1.39 Mg m−3 over 1.48 Mg m−3 under farmer's practice). Sugarcane ratoon crop removed the highest amount of nitrogen (N—165.7 kg ha−1), phosphorus (P—24.01 kg ha−1) and potassium (K—200.5 kg ha−1) in the plots receiving FYM with Trichoderma and Gluconacetobacter. Inoculation of FYM with bioagents improved population of ammonifying and nitrifying bacteria in the soil. Phosphorus and potassium uptake of the crop was greatest in the plots receiving FYM, Trichoderma and Gluconacetobacter. Bioagents (Trichoderma and Gluconacetobacter) amended FYM increased ratoon cane (70.2 Mg ha−1) and sugar yields (7.93 Mg ha−1) compared with control (62.3 and 7.06 Mg ha−1 ratoon cane and sugar yields, respectively).