Water Regimes and Seeding Rates Influence Grain Yield and Water Use Efficiency of Three Durum Wheat Varieties
Afef Othmani *
Field Crops Laboratory, University of Carthage, Regional Research Development, Office of Agriculture in Semi Arid North West of Kef, Tunisia.
Sourour Ayed
Field Crops Laboratory, University of Carthage, National Agricultural Research Institute of Tunisia, Rue Hédi Karray, 2049 Ariana, Tunisia.
Mohsen Rezgui
University of Carthage, Science and Agronomic Techniques Laboratory, National Agricultural Research Institute of Tunisia, Kef Station, Tunisia.
Mongi Melki
Higher Agriculture School of Kef, Tunisia.
Jaime A. Teixeira da Silva
Independent, Miki-cho Post Office, P. O. Box 7, Ikenobe 3011-2, Kagawa-ken, 761-0799, Japan.
*Author to whom correspondence should be addressed.
Abstract
In order to establish the optimal level of irrigation and seeding rate to achieve high grain yield and water use efficiency (WUE) for durum wheat (Triticum durum Desf.) in a Tunisian semi-arid region, three durum wheat varieties (Maâli, Nasr and Chili) were evaluated under four levels of irrigation (I3: 70% of field capacity (FC); I2: 40% FC; I1: 10% FC; I0: rainfall) and five seeding rates (D1: 250, D2: 300, D3: 350, D4: 400, D5: 450 seeds/m2). The level of irrigation significantly affected all traits except for 1000-kernel weight. I3 induced maximum grain yield (GY) (106.7 q/ha), number of spikes/m2 (607.8), number of kernels/spike (51.09), 1000-kernel weight (50.45 g) and biomass yield (BY) (349 q/ha) while the rainfed treatment (I0) showed the lowest values. GY and BY were positively correlated (r = 0.6) with number of spikes/m2. Highest WUE of grain yield (WUEg) and of biomass yield (WUEb) were observed under moderate irrigation (I2) and exceeded values obtained under the highest water regime (I3) by 11.08% and 7.9%, respectively. Seeding rate D3 showed lowest mean values of GY (71.10 q/ha), BY (238 q/ha), WUEg (1.49 kg/m3) and WUEb (4.96 kg/m3). WUEg was positively correlated to harvest index (r = 0.45).The WUEg and GY of Maâli (91.63 q/ha) were significantly higher than those of Nasr (83.88 q/ha) and Chili (66.16 q/ha). However, Chili had the highest BY. There was no significant difference in the WUEb of all three varieties. Although there was no interaction between water regimes, seeding rates and varieties, a moderate irrigation regime and high or low seeding rate are recommended to achieve high WUE.
Keywords: ABO blood group, Grain yield, Association of Tuberculosis, irrigation, ABO gene frequencies., seeding rate, water use efficiency, wheat, yield components.