Genetic variation in the efficiency of nitrogen utilization and photosynthetic activity of flag leaves among the old and modern germplasm of winter wheat

Abstract

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.

Effect of Fertilizer and Fixed Nitrogen on the Water Use Efficiency of Genge (Astragalus sinicus L.)

“…4). This supports the results reported by Hubick (1990), Górny and Garczyński (2002), and Hamaoka et al (2013). However, Brueck and Senbayram (2009), who conducted a quantitative analysis of the influence of N supply on tobacco WUE, reported that WUE and DM proportionally increase with increases in N supply.…”

“…In this case, the reduction in WUE observed in nodulated plants casts doubt on the association with BNF and suggests that it is driven by N excess. The difference in WUE between nodulated plants and non-nodulated plants can only be directly related to N fixation cost when WUE has no relationship with the internal N conditions of plants (Hubick, 1990;Górny andGarczyński, 2002; Hamaoka et al, 2013). There is an optimum curvilinear relationship between 【Short Report】 plant growth rates and N concentration in culture medium (Hozumi et al, 1960); plant growth rates are reduced under either conditions of N shortage or N excess.…”

Mode of inheritance of low-N tolerance adaptive traits in wheat (Triticum aestivum L.) under contrasting nitrogen environments

“…Although numerous reports on genotypic variation in components of N efficiency already suggest potential applications of this genetic knowledge for wheat improvements (Ortiz-Monasterio et al, 1997;El Bassam, 1998;Le Gouis et al, 2000;Gorny et al, 2006;Kichey et al, 2007;Baresel et al, 2008;Barraclough et al, 2010), relatively fewer attempts have been made to breed wheat for these traits (Van Ginkel et al, 2001;Wolfe et al, 2008). Progress in breeding bread wheat better adapted to less favorable nitrogen fertilization is still restricted for several reasons.…”

Inheritance of the efficiency of nitrogen uptake and utilization in winter wheat (Triticum aestivum L.) under diverse nutrition levels

“…Different morphophysiological characteristics, associated with both the uptake capacity (NUpE; defined here as a proportion of total N uptake to N availability in the soil) and efficiency of nitrogen utilization in grain mass formation (NUtE; defined here as the grain mass formed per unit of N absorbed), appear to be critical components of NUE (Moll et al 1982;Huggins and Pan 2003). Although numerous reports on genotypic variation in components of N efficiency already suggest potential applications of this genetic knowledge for wheat improvements (Dhugga and Waines 1989;Le Gouis and Pluchard 1996;Ortiz-Monasterio et al 1997;El Bassam 1998;Le Gouis et al 2000;Oracka et al 2000;Górny et al 2006a;Laperche et al 2006a;Kichey et al 2007;Baresel et al 2008;Barraclough et al 2010), relatively fewer attempts have been made to breed wheat for these traits (Van Ginkel et al 2001;Brancourt-Hulmel et al 2005;Löschenberger et al 2008;Wolfe et al 2008).…”