Phosphorus use efficiency, grain yield, and quality of triticale and durum wheat under irrigated conditions

After nitrogen stress, phosphorus is the second most widely occurring nutrient deficiency in cereal systems around the world. The objectives of this study were: (1) to look at the effect of changes in phosphorus use efficiency and responsiveness on grain yield and quality of triticale and durum wheat with respect to an old tall durum wheat of the early 1940s, Barrigon Yaqui. A two-year field experiment was established at the CIANO research station in Cd. Obregon, Sonora, Mexico. The experimental design used was a split-plot, main plots were two levels of phosphorus (0 vs 80 kg P2O5), and subplots were 20 genotypes [10 durum wheat (1-10) and 6 triticale (11-20)] with three replications. The effect of phosphorus deficiency was severe: only 43% of the achievable yield was obtained with no P application. The modern durum wheat and triticale genotypes included in this study equaled Barrigon Yaqui in phosphorus use efficiency (performance under low P conditions). In contrast, all modern durum wheat and triticale genotypes (except for Tehuacan 60, Tehuacan 67, and Beagle_1) were more responsive to P applications with grain yields in some genotypes almost three times higher in the 80 kg P2O5 application treatment. Percent grain protein on average was higher in durum wheat than in triticale. Within durum wheat, compared to Barrigon Yaqui, most durum genotypes were the same except for Cocorit 71, Mexicali 75, and Altar 84, which had lower percent grain protein when well fertilized with P. Compared to Barrigon Yaqui, all triticale genotypes had lower percent grain protein. Under high P conditions, the early durum Cocorit 71 and all durum genotypes from Aconchi 89 onwards had higher sedimentation values than Barrigon Yaqui. In contrast, all triticales were not significantly different from Barrigon Yaqui.