The effect of plot-to-plot irrigation on soil chemical characteristics and yield of Shiroudi variety rice

In order to study the effect of plot-to-plot irrigation method on soil chemical characteristics and rice yield, a randomized block experiment was conducted in the research farm of the Faculty of Agricultural Sciences of University of Guilan. This research was done in three repetitions and each repetition included six plots which were named plot by plot in a vertical row from 1 to 6. The quality characteristics of the soil were evaluated at two depths of 0 to 15 and 15 to 30 cm, as well as grain yield. The results showed that the highest salinity (3.8 mmhos/cm), total soluble solids (2316.6 mg/l), nitrate (6.3 mg/l), sodium (407.5 mg/l), calcium (410.8 mg/L), and sodium absorption ratio (5.6 me/L) were observed at the depth of 0 to 15 cm in the sixth plot. But, the highest grain yield with 9035.54 kg/ha was related to the fourth plot. Despite the same agricultural operations in the plots, the amounts of nutrients, soil soluble salts and grain yield were different in them, which could be due to the difference in the amount of nutrients in the plots. Therefore, in order to prevent their amount from changing from one plot to another, the necessary opportunity for the absorption of water nutrients and soil solution by the plant in the plots should be created to affect the final yield. In general, due to the reduction of only 5.92 and 4.33 percent of paddy yield in the sixth plot compared to the fourth and first plots, respectively, it seems that due to the limited water resources in the north of the country, the use of plot-to-plot irrigation for planting Rice needs more and more detailed investigation in order to achieve the highest growth and yield in the region.