Interaction of Different Water Amounts and Phosphorus and Magnesium Doses and Their Effects on Water-Yield Relations of Soybean (Glycine max L.) in Arid Conditions

Abstract

This field experiment examined the effects of magnesium (Mg) and phosphorus (P) fertilizers, which were given in different doses to soybean grown in different water levels, on plant water consumption, water-yield relations and grain yield factors. The experiment used a random blocks designed with three consecutive and was conducted over two years 2006 and 2007. Four different P doses (0-4-8-12 kg P da-1) and three different Mg doses (0-4-8 kg Mg da-1) were applied with three different water levels (I1, I2, I3). Cumulative pan values obtained from Class A Pan evaporation pool were applied as irrigation (I) 33% for I1, 67% for I2, 100% for I3. At the end of experiment were determined plant water consumption, water-yield relations and grain yield. At the start of irrigation, 548.00 mm, 786.00 mm and 1 017.00 mm of water were given to I1, I2 and I3 plots, respectively in the first year, and 457.98 mm, 698.02 mm and 931.00 mm irrigation water was given in the second year. Plant water consumption values (ETa) were determined as 648.00 mm, 903.00 mm and 1164.00 mm for I1, I2 and I3 parts in the first year, and 567.00 mm, 825.00 mm and 1070.00 mm in the second year. Moreover, according to experiment plots, irrigation water treatment efficiency (IWTE) varied between 0.14 and 0.53 kg m-3 in the first year and between 0.16 and 0.59 kg m-3 in the second year.