11. Accumulation and reutilization of barley dry mass dependening on fertilization

Author: Svetla Kostadinova

DOI: n/a

Abstract

The dry mass accumulation and reutilization of the Krami barley cultivar depending on the fertilizing levels were studied: 1). Unfertilized control (N0Р0K0); 2). Nitrogen fertilization – 100 kg/ha and omission of phosphorus and potassium fertilization (N100Р0К0); 3). Phosphorus fertilization – 80 kg Р2О5/ha and omission of nitrogen and potassium fertilization (N0Р80К0); 4). Combined nitrogen-phosphorus fertilization – 100 kg N with 80 kg Р2О5/ha (N100Р80К0). It was established that nitrogen-phosphorus fertilization N100P80 did not change the ratio of the pre-anthesis dry mass accumulation of barley to the synthesized dry mass after anthesis, compared to the unfertilized plants. Nitrogen or phosphorus fertilization alone affected in a different mode the dry mass translocation – nitrogen fertilizing demonstrated more dry mass accumulation in the pre-anthesis period, and phosphorus fertilization increased the dry mass accumulation after anthesis. The dry mass reutilization of the fertilized plants was higher by 57% in average, which was an indicator that fertilization led to a higher dry mass reutilization of barley plants. The spike dry mass during anthesis constituted 24.4 – 27.3% of the barley aboveground biomass in anthesis and depended little on fertilizing. Nitrogen fertilization (N100 alone or combined with Р80) ncreased by 80% in average the amount of reutilized pre-anthesis biomass while the phosphorus fertilization alone did not alter significantly the reutilized dry mass compared with the unfertilized plants. The independent phosphorus fertilization altered the pattern of barley dry mass distribution and reutilization by translocation of less dry mass, lower translocation efficiency and lower contribution of pre-anthesis vegetative assimilates to the grain.