GRAIN FILLING OF DURUM WHEAT THROUGH ASSIMILATE REMOBILISATION UNDER SEMI-ARID CONDITIONS

• Published in: Experimental agriculture Vol. 49; no. 2; pp. 197 - 211
• Main Authors: LATIRI, K., LHOMME, J. P., LAWLOR, D. W.
• Format: Journal Article
• Language: English
• Published: Cambridge, UK Cambridge University Press 01.04.2013
• Subjects: Agricultural production; Cultivars; Field tests; Growing season; Nitrogen; Water supply; Wheat; Tunisia
• ISSN: 0014-4797; 1469-4441
• DOI: 10.1017/S0014479712001238

In a context of understanding the physiological mechanisms and cultivar traits which could improve durum wheat (Triticum durum) yield in water limited conditions, the paper focuses on the contribution of stored assimilates to grain growth and yield. A conceptual model describing the different fluxes of assimilate during the grain filling period is used together with a dataset from field experiments made in northern Tunisia during two growing seasons and under different conditions of water and nitrogen supply. Three types of behaviour have been encountered in relation to the balance between demand for assimilate and supply. Remobilisation of stored assimilates provides a buffer enabling grain growth to be maintained. Conditions at anthesis play an important role in determining the type of fluxes of assimilates. Grain number also plays a major role in short- or long-term remobilisation and grain number per ear increases short-term remobilisation. In rain-fed conditions, short-term remobilisation allows faster grain growth.