Relationships between cold tolerance, grain yield performance and stability of durum wheat (Triticum durum Desf.) genotypes grown at high elevation area of Eastern Algeria

Abstract

To increase grain yield in the North African high plateaus, selection of durum wheat (Triticum durum Desf.) was accompanied by an early heading for effective utilization of the limited soil moisture and to escape terminal drought and heat stresses. Early genotypes suffer however seriously from low temperature damage during cold season. Developing cultivars resistant to low temperature stress appears critical to avoid crop failure and to stabilize grain yield. The objectives of the present study were to evaluate the genotypic variability for resistance to low temperatures using artificial tests and to investigate the relationship between the results of such tests and the agronomic performance and stability of a field grown set of durum wheat (Triticum durum Desf.) genotypes. The artificial laboratory tests employed enabled genotypes to be differentiated on the basis of their cold tolerance, results suggest that genotypes which possess the ability to cold acclimate during winter retain this feature until the booting stage. Means of agronomic traits varied significantly between seasons and genotypes, indicating the presence of significant genotypic variability and differential responses to the growth conditions experienced. No consistent relationships, between the tolerance to low temperatures and agronomic performances, were found due to the confounding effects of terminal heat and drought stresses, acting on the same yield components as the cold stress. Early, freezing tolerant and above average yielding cultivars were identified which serve as genetic source to improve tolerance to low temperatures in short cycle genetic background. © 2006 Asian Network for Scientific Information.