Dry matter and nitrogen accumulation by standard height and semi-dwarf barley isotypes

Abstract

To assess nitrogen movement from the soil into the plant and within the plant, studies of dry matter and N accumulation are necessary. The objective of this experiment was to study the effect of 30, 60, 90 and 120 kg of N/ha on dry matter and N accumulation by four standard height-semi-dwarf normal mutant malting barley isotype pairs (Morex, Hazen, Norbert, Andre) and two check cultivars: Steptoe and Klages. Considerable differences among genotypes on dry matter accumulation until anthesis and dry matter lost during grain filling period were observed. Genotypic differences for pre-anthesis (range: 36.6 to 52.9 mg N/plant) and post-anthesis (range: -2.3 to 10.8 mg N/plant) N accumulation and in total N accumulation (range: 69 to 149.2 mg N/plant in 1987 and 41.3 to 56.5 mg N/ha in 1989) were observed. Within the isotype pairs, consistent differences were detected for post-anthesis and total N accumulation both favoring the standard isotypes. These differences were not affected by fertilizer N levels. Genotypic differences in N remobilization into the grain were also observed. Relationship between N and dry matter partitioning are discussed.