Response of maize crop to biochar produced at varied temperature in eastern dry zone of Karnataka

In recent years, there has been a substantial increase in the widespread application of agrochemicals to enhance crop yields, thereby posing a considerable risk to soil health. In this regard, biochar application has gained considerable interest due to its potential to enhance crop growth and yield by improving fertilizer use efficiency and reducing use of agrochemicals. However, there is limited understanding how biochar produced at different temperature affects crop growth and yield. Pot experiment was conducted with maize crop to study the impact of biochars from simarouba seed coat produced at different pyrolysis temperatures (300, 400, and 500 °C), integrated with different proportions of inorganic and organic fertilizers. Results showed that, integrated application of biochar produced at 300 °C, combined with 75 per cent RDF, and 25 per cent Simarouba seed cake (T₅), exhibited notablyhigher plant height, number of leaves, leaf area per plant at 60 and 90 DAS. This ultimately resulted in improved yield parameters like cob length (16.93 cm), cob girth (12.78 cm), number of seeds per cob (474.90), test weight of kernels (24.03 g), grain yield per plant (114.09 g), and overall dry matter production per plant (207.21 g) in the treatment. Grain yield and stover yield per hectare was calculated and found highest in T₅ (6339 and 7762 kg respectively). The results of T₅ were on par with T₂ where biochar produced at 300 °C and 100 per cent RDF was applied. Among all the treatments employed, T₅ was concluded to be the most effective and cost-efficient, offering a reduction in the use of chemical fertilizers by 25 percent, coupled with an approximate 30 percent increase in grain yield per hectare of maize crop.