Growth, nutrient accumulation and crop yields as influenced by crop residues recycling and Trichoderma inoculation in rice (Oryza sativa)-wheat (Triticum aestivum) and sugarcane-ratoon-wheat cropping systems in subtropical India

A field experiment was conducted during 2013-15 at the ICAR-Indian Institute of Sugarcane Research, Lucknow, Uttar Pradesh study the effect of crop-residues recycling and Trichoderma inoculation on growth, nutrient accumulation and crop yields in 2 cropping systems, viz. rice (Oryza sativa L.)-wheat (Triticum aestivum L.)- rice-wheat and sugarcane-ratoon-wheat. The experiment was laid out in a split-plot design, with cropping systems in main plots and residues management practices in subplots. Among the different crop residue treatments, the highest available N (222.8 kg N/ha and 164.8 kg/ha at 0-15 and 15-30 cm depth, respectively) was recorded in the treatment where full residue was recycled along with Trichoderma. The leaf-area index was higher in wheat (3.97) than rice crop (3.07) at the maximum growth stage. Wheat crop grown in sugarcane-based system accumulated higher dry matter (8.02 t/ha) than wheat grown in rice-wheat system (7.71 t /ha). A significant increase in cane-equivalent yield was obtained in sugarcane-based system as compared to rice-wheat system. Cane-equivalent yield ranged from 103.3 to 138.3 t/ha in sugarcane-ratoon-wheat system, considering yields of ratoon-cane and wheat crops. Residue recycling + Trichoderma resulted in higher cane-equivalent yields in both the cropping systems. The residue burning/ removal caused significantly low yields in succeeding crop and cane-equivalent yields in both the cropping systems. The benefit: cost ratio (2.96) was the highest with sugarcane-ratoon-wheat cropping system under residue recycling + Trichoderma. Thus, residue recycling along with application of Trichoderma proved effective in both the cropping systems, but higher benefits could be achieved under sugarcane-ratoon-wheat cropping system.