Modelling the effects of climatic change and genetic modification on nitrogen use by wheat

• Published in: European journal of agronomy 1995, Vol.4 (4), p.419-429
• Main Authors: Porter, J.R., Leigh, R.A., Semenov, M.A., Miglietta, F.
• Format: Article
• Language: English
• Subjects: ABONOS NITROGENADOS; Adaptation to environment and cultivation conditions; Agricultural and forest climatology and meteorology. Irrigation. Drainage; Agricultural and forest meteorology; Agronomy. Soil science and plant productions; APLICACION DE ABONOS; Biological and medical sciences; CAMBIO CLIMATICO; CEREAL CROPS; climate change; CLIMATIC CHANGE; Climatic models of plant production; CULTIVOS DE CEREALES; ENGRAIS AZOTE; FERTILISATION; FERTILIZER APPLICATION; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Generalities. Techniques. Climatology. Meteorology. Climatic models of plant production; GENETIC ENGINEERING; genetic modification; Genetics and breeding of economic plants; GENIE GENETIQUE; INGENIERIA GENETICA; METABOLISME DE L'AZOTE; METABOLISMO DEL NITROGENO; MODELE DE SIMULATION; modelling; MODELOS DE SIMULACION; NITROGEN FERTILIZERS; NITROGEN METABOLISM; nitrogen use; NUTRICION DE LAS PLANTAS; NUTRITION DES PLANTES; PLANT NUTRITION; PLANT SOIL RELATIONS; PLANTAS TRANSGENICAS; PLANTE CEREALIERE; PLANTE TRANSGENIQUE; RELACIONES PLANTA SUELO; RELATION PLANTE SOL; SIMULATION MODELS; TRANSGENIC PLANTS; TRITICUM AESTIVUM; VARIATION DU CLIMAT; Varietal selection. Specialized plant breeding, plant breeding aims; wheat
• ISSN: 1161-0301; 1873-7331
• DOI: 10.1016/S1161-0301(14)80094-4

This paper considers how and the extent to which climate change and the balance of nitrogen between crops and soils may interact and how the ability to modify genetically specific crop attributes might affect the overall nitrogen balance of the crop-soil system. The possible effects of each change have been assessed using the AFRCWHEAT2 crop model for wheat. Model output pointed to a decrease in harvest index as a result of coincidental increases in CO2 level and temperature, and the importance of considering not only changes to average but also to the variability of environmental driving variables is illustrated. When mean temperatures were raised the model predicted that more nitrate would be left in the soil at the end of the season but that raising CO2 level could counter this effect. Doubling the variability of temperature had a more complicated effect on the soil N balance with the mean amount of residual soil nitrate predicted to be at about the same level as for the baseline and with only a comparatively small change in its coefficient of variation. These results are interpreted in terms of a bell-shaped response of mineralisation rate to temperature. Raising the value of the maximum N concentration (Nmax) in the shoots increased the amount of NO3-N extracted from the soil. However, the overall effects were not simply proportional to the increase in Nmax because the crop could also become limited by the supply of N from the soil.