Variation of Grain Yield, Grain Protein Content and Nitrogen Use Efficiency Components under Different Nitrogen Rates in Mediterranean Durum Wheat Genotypes
Sawsen Ayadi,
Salma Jallouli,
Zoubeir Chamekh,
Inès Zouari,
Simone Landi,
Zied Hammami,
Fatma Ezzahra Ben Azaiez,
Mokhtar Baraket,
Sergio Esposito,
Youssef Trifa
Affiliations
Sawsen Ayadi
National Institute of Agronomy of Tunisia, Carthage University, LR-14-AGR-01, Cite Mahragène, Tunis 1082, Tunisia
Salma Jallouli
National Institute of Agronomy of Tunisia, Carthage University, LR-14-AGR-01, Cite Mahragène, Tunis 1082, Tunisia
Zoubeir Chamekh
National Institute of Agronomic Research of Tunisia, Carthage University, LR20-INRAT-02, Menzah I, Tunis 1084, Tunisia
Inès Zouari
National Institute of Agronomy of Tunisia, Carthage University, LR-14-AGR-01, Cite Mahragène, Tunis 1082, Tunisia
Simone Landi
Dipartimento di Biologia, Complesso Universitario Monte Sant’Angelo, Universita di Napoli Federico II, 80126 Naples, Italy
Zied Hammami
International Center for Biosaline Agriculture, Dubai P.O. Box 14660, United Arab Emirates
Fatma Ezzahra Ben Azaiez
National Institute of Agronomy of Tunisia, Carthage University, LR-14-AGR-01, Cite Mahragène, Tunis 1082, Tunisia
Mokhtar Baraket
National Research Institute of Rural Engineering, Water and Forests (INRGREF), Tunis 1004, Tunisia
Sergio Esposito
Dipartimento di Biologia, Complesso Universitario Monte Sant’Angelo, Universita di Napoli Federico II, 80126 Naples, Italy
Youssef Trifa
National Institute of Agronomy of Tunisia, Carthage University, LR-14-AGR-01, Cite Mahragène, Tunis 1082, Tunisia
Nitrogen (N) is a crucial nutrient for plant growth and development. To optimize agricultural environments, N fertilizers represent a critical tool to regulate crop productivity. The improvement of nitrogen use efficiency (NUE) represents a promising tool that may enable cereal production to meet future food demand. Wheat reported contrasting behaviors in N utilization showing specific abilities depending on genotype. This study selected two landraces and two improved genotypes from Northern Africa to investigate grain yield (GY), grain protein content (GPC) and NUE. Plants were grown under three levels of N supply: 0, 75, 150 kg N ha−1 and for two consecutive years. Results reported a better NUE (0.40 kg kg N−1) obtained under 150 kg N ha−1, while N utilization efficiency (NUtE) showed a 13% increase using 75 kg N ha−1 compared with 150 kg N ha−1. Under low nitrogen rate (0 N), crop N supply (CNS) and N uptake efficiency (NUpE) were shown as determinant factors for improved genotypes GY (R2 = 0.72), while NUtE represented the most determinant component for GPC in landraces (R2 = 0.92). Multivariate regression models explained the dependence in GPC on NUE, NUpE, and NUtE. In conclusion, our results recognize GPC and NUtE as suitable selection traits to identify durum wheat with higher NUE.
