Characterizing nitrogen use efficiency in natural and agricultural ecosystems to improve the performance of cereal crops in low-input and organic agricultural systems

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

“…Except for Gw/Ng in the field experiment, the physiological measures of N efficiency tended to increase under low N. Noteworthy, however, the magnitude of the N-induced alterations in the majority of the efficiency components was distinctly dependent upon the genotype, as evident by the significant genotype 9 environment interactions. The result is consistent with observations previously reported in wheat (El Bassam 1998;Le Gouis et al 2000, barley (Ceccarelli 1994(Ceccarelli , 1996Górny and Sodkiewicz 2001) and maize (Di Fonzo et al 1982;Medici et al 2004;Presterl et al 2008), corroborating that an evaluation of breeding materials under diverse fertilization regimes is necessary for choice of the most efficient parental forms and/or cross combinations, as suggested by others (Brancourt-Hulmel et al 2005;Laperche et al 2006a;Dawson et al 2008;Wolfe et al 2008).…”

“…This relationship was particularly evident in the field experiment under low N at Poznań (r = -0.92, P \ 0.01) indicating that, at least in the examined wheat assortment, a reduced uptake capacity of an entry was usually connected with its more efficient utilization when absorbed, and vice versa. High-yielding crops from intensive ecosystems tend to be less efficient in the nutrient uptake and an improved crop adaptation to conditions of reduced N-input is frequently reported to be mainly associated with enhanced NUpE (Gastal and Lemaire 2002;Dawson et al 2008;Presterl et al 2008). It is well known that at least some important genes responsible for N uptake (e.g.…”

“…Hence, several important queries remain to be resolved, especially in regard to the most effective selection schemes, desirable plant ideotypes for lowinput ecosystems, appropriate selection criteria and features of the selection environment or cropping systems necessary for such breeding programs (e.g. Ceccarelli 1996;Dawson et al 2008;Wolfe et al 2008). Furthermore, modern European wheat cultivars are phenotypically different but, in essence, represent a limited gene pool.…”

Assessment of nutrient use in annual and perennial crops: A functional concept for analyzing nitrogen use efficiency

“…for assessment of the NUE of perennial crops. This aspect was recognised by Dawson et al (2008), suggesting the calculation of the amount of N carried over to the following year as part of an integrated NUE concept especially for perennial crops. However, a general NUE concept should consist of the same components for all agricultural crops, irrespective their annual or perennial nature.…”

“…In future, we need to integrate the research performed to evaluate the different aspects of crop NUE at the molecular, single-plant and agro-ecosystem levels with the needs of applied agronomic research, including the selection and breeding of cultivars for low-input and organic cropping systems (Dawson et al 2008;Spiertz and Ewert 2009). The proposed concept could contribute to such integration by offering a common basis for the evaluation of the various crop types and research activities dealing with different NUE aspects.…”