Genetic variation in the efficiency of nitrogen utilization and photosynthetic activity of flag leaves among the old and modern germplasm of winter wheat.
Genotypic variation in major components of the efficiency of nitrogen utilization and photosynthetic activity of flag leaves among old (released 1881-1963) and modern (released 1969-2003) cultivars of winter wheat was studied in field conditions under varied N fertilization levels (110, 90 and 80 kg N ha-1). Significant genotypic differences were observed for all characters. Their heritabilities ranged from 0.37 to 0.93 and were the lowest for the leaf efficiency of gas exchange, photosynthetic rate, straw N content and the economic index of N utilization efficiency (NUE). Some modern cultivars exhibited an enhanced tolerance to N shortage and several attributes of efficient N utilization (e.g. later senescing and more photosynthetically active flag leaves, increased ability to redistribute N into grains). The genotypes may serve as donors of appropriate characteristics for breeding. The observed cultivar-by-fertilization interactions suggest, however, that evaluations under diverse fertilization regimes may be necessary when searching for improved wheat efficiency and adaptation to less favourable environments.
Górny
Andrzej G
AG
Institute of Plant Genetics, Polish Academy of Sciences, Strzeszynska 34, 60-479 Poznań, Poland. agor@igr.poznan.pl
Garczyński
Sebastian
S
Banaszak
Zofia
Z
Ługowska
Bogusława
B
D000222:Adaptation, Physiological; D000704:Analysis of Variance; D001947:Breeding / Q000379:methods; D014644:Genetic Variation; D005838:Genotype; D009584:Nitrogen / Q000378:metabolism*; D010788:Photosynthesis / Q000235:genetics / Q000502:physiology*; D018515:Plant Leaves / Q000235:genetics / Q000502:physiology*; D019655:Quantitative Trait, Heritable; D013045:Species Specificity; D014908:Triticum / Q000235:genetics*
D009584:Nitrogen