Nitrogen uptake and expense in durum wheat depending on genotype and nitrogen fertilization

Abstract

Abstract. Nitrogen uptake and expense of durum wheat were studied under the conditions of fertilized field experiment on soil type Pellic vertisol. The seven genotypes - Progress, Vazhod, Victoria, Predel, Deana, Zvezdica and Elbrus selected at the Institute of Field Crops – Chirpan, Bulgaria, were grown in two field crops rotation of cotton and durum wheat under rainfed conditions for a period of three vegetations in years 2011-2013. The spring treatments of nitrogen as NH NO were as follows: N , N , N and N . The total N uptake in the above ground biomass of durum wheat increased with the amount of applied nitrogen 4 3 0 60 120 180 -1 and during climatically favorable years reached 220 kg N.ha . A tendency was found that the new genotypes uptook more N, compared to varieties Progress and Vazhod. The N expense of the new cultivars Predel and Zvezdica showed the highest amount of N per 1 ton of grain, 40.7 and 41.1 kg, respectively. Strong positive correlation was found between N fertilization and N uptake and expense for 1 ton of grain. The regression model indicated that N uptake with the grain -1 and straw and N expense depending on N fertilization occurred with delay. With N fertilization of durum wheat at rates of up to 180 kg N.ha each kilogram of -1 -1 applied N fertilizer increased the average expected N uptake with 7 kg.ha and N expense with 0.66 kg.ton grain.

Keywords

• durum wheat
• genotype
• nitrogen
• uptake
• expense