Effects of Increasing Doses of Nitrogen and Different Zinc Application Methods on Dry Matter Yield and Element Concentrations at the Beginning of Flowering Stage of Quinoa Plant
This study was conducted to determine the effects of different doses of N (100, 250, 500, 750 and 1000 mg kg-1) and different Zn application methods [non Zn application (Zn0), soil application of Zn (5 mg kg-1), soil + foliar application of Zn (5 mg kg-1 + 0.2%)] on shoot dry matter yield, N and Zn concentration of the shoot of quinoa (Chenopodium quinoa Willd.) at the beginning of flowering stage. The dry matter yield increased depending on increase in doses of N. These increases were determined as 11%, 16%, 35%, 31% and 20%, respectively, compared to the control application (50 mg N kg-1). The highest yield increase was at the rate of 500 mg kg-1 N, which was increased also at the subsequent treatments compared to the control, but insignificant decreases were seen compared to the 500 mg kg-1 N application. In parallel with the increase in N dose, the N concentration of the plant has also increased. Nitrogen concentration varied from 1.70 to 4.51% and increased by 31%, 148%, 153%, 161% and 165%, respectively, with increasing N applications. Unlike dry matter yield, the highest increase (88.9%) was determined in the application of 250 mg kg-1 N according to the previous application, and lower or close increments (4.5%, 2.3% and 2.2%) were detected in subsequent applications. It was determined that increasing doses of N and different Zn application methods increased Zn concentration in the plant
and that the mean concentration varied between 42.2-51.3 mg kg-1. Plant Zn concentrates under all N doses applied were ranged as control<soil application of Zn <foliar application of Zn< soil + foliar application of Zn and the differences between Zn applications compared to control were statistically significant. It has been determined that the most suitable Zn application method was the application of Zn to the soil + leaf and increasing doses of N application and different Zn application methods increased the dry matter yield, N and Zn concentration of the shoot
