Investigation of the Effect of Biochar and Different Sources of Nitrogen on the Growth Characteristics of Rice (Oryza sativa L.)

This study was conducted to investigate the effects of biochar and nitrogen sources on agronomic traits and soil and plant nitrogen in rice Tisa in Tonekabon rice research station. The statistical design used was factorial in the form of randomized complete blocks with three replications. The treated treatments included biochar at three levels (control, 20 and 40 t ha−1) and nitrogen sources at three levels (control, nitrogen fertilizer at 200 kg ha-1 and inoculation of seeds with nitrogen-fixing bacteria (Azospirillum, Aztobacter and Pseudomonas). The results showed that among different nitrogen sources, the application of nitrogen chemical fertilizer led to a significant increase in some yield components, grain yield and nitrogen concentration in the plant, so that the number of fertile tillers per hill, grain yield, and nitrogen concentration in the grain and straw were increased by about 20.4%, 33.6%, 17.8% and 24.7%, respectively, compared to the control or without use of nitrogen.The results showed that in field conditions the interaction of treatments (Nitrogen chemical fertilizer × 20 tha−1 biochar, nitrogen chemical fertilizer × t ha−1 biochar, bacterial application × 20 t ha−1 biochar, bacterial application × 40 t ha−1 biochar) on straw nitrogen was significant. Nitrogen application in field conditions led to a significant increase in plant height, number of fertile tillers per mound, grain yield, biological yield and nitrogen concentration in grain. In greenhouse conditions the highest grain yield (90.71 g) in the interaction application of nitrogen fertilizer With 40 t ha−1 biochar of and the highest concentration of grain nitrogen (0.64 mg kg-1) were observed in bacterial inoculation treatment with 40 t ha−1. According to the results of this study, the application of nitrogen fertilizer in the amount of 200 kg ha-1 to achieve maximum rice grain yield and also the use of biochar in the amount of 20 and 40 t ha−1 to improve soil fertility is recommended.