The efficiency of a durum wheat-winter pea intercrop to improve yield and wheat grain protein concentration depends on N availability during early growth

L. Bedoussac¹ and E. Justes²

Abstract  
Grain protein concentration of durum wheat is often too low, particularly in low-N-input systems. The aim of our study was to test whether a durum wheat-winter pea intercrop can improve relative yield and durum wheat grain protein concentration in low-N-input systems.

A 2-year field experiment was carried out in SW France with different fertilizer-N levels to compare wheat (Triticum turgidum L., cv. Nefer) and pea (winter pea, Pisum sativum L., cv. Lucy) grown as sole crops or intercrops in a row-substitutive design.

Without N fertilization or when N was applied late (N available until pea flowering less than about 120 kg N ha⁻¹), intercrops were up to 19% more efficient than sole crops for yield and up to 32% for accumulated N, but were less efficient with large fertilizer N applications. Wheat grain protein concentration was significantly higher in intercrops than in sole crops (14% on average) because more N was remobilized into wheat grain due to: i) fewer ears per square metre in intercrops and ii) a similar amount of available soil N as in sole crops due to the high pea N₂ fixation rate in intercrops (88% compared to 58% in sole crops).


Source
Plant and Soil (2010) 330: 19-35


Author Locations & Affiliations
(1) Université de Toulouse, UMR 1248 Agir, F-31326 Castanet Tolosan, France
(2) INRA, UMR 1248 Agir, F-31326 Castanet Tolosan, France


Posted April 2010