Title: Determination of NPK requirement of two promising lines AN-74 and AHS through omission plots
Author: Mohammad Mohammadian
Abstract: Variation in early maturity and high-quality Promising lines is one of the aims of the Rice Research Institute so that farmers have a wider range of varieties available for cultivation. superior lines of compatibility experiments. before introducing, it is necessary to investigate some aspects of their agronomic management. Important aspects of agronomic management are the NPK requirements of introduced lines. In order to investigate the need for AN-74 and ASH lines to macronutrients of nitrogen, phosphorus, and potassium, a field experiment was carried out for two years from 2018 in Rice Research Institute-Deputy of Mazandaran. The experiment for each line consisted of 4 treatments including 3 omission plots N0, P0, and K0 and NPK + Zn treatment. In the omission plot, except desired nutrients, all other nutrients were added., In the NPK + Zn plot, all nutrients were consumed adequately. After consumption of basic fertilizers, 2 to 3 30 days old seedlings of AN-74 and ASH lines were transplanted. Dimensions of plots were 6 × 8 m and transplanting distance was 25 × 25 cm. crop practices such as weeding, pests, and diseases management carried out uniformly in all plots. A 12-plant sample was prepared at the physiological maturity stage to determine biomass, straw yield, and harvest index. Grain yield was obtained from 3 harvested area of 5m2 that located in the center of each plot and Grain yield calculated on basis of standard moisture content of 14 percent. SAS statistical software was used for data analysis. Based on the two-year results of the experiment, the highest mean of grain yield of AN-74 and ASH lines obtained from NPK treatment as many as 4818 and 4176, respectively. The results showed that to achieve attainable grain yield of AN-74 and ASH line, it needs to application of 69 and 55 kg ha -1 N, 46 and 40 kg ha -1 P2O5 and 35 and 30 kg ha -1 K2O, respectively in the soil conditions of Rice Research Institute of Mazandaran.
Keywords: Rice, Omission plots, Promising line