Response of Eight Flax Cultivars to Some Growth and Yield Traits Under Different Levels of Water Stress

A field experiment was conducted in Al-Hussainiya District, 20 km northeast of Karbala province, during the winter season (2023-2024) to study the effect of water stress on several flax cultivars. The experiment was implemented in a split-plot arrangement according to a randomized complete block design (RCBD) with three replicates. The main plots included three levels of water stress (line treatment, 50% depletion of available water, 70% depletion of available water, and 90% depletion of available water), while the sub-plots included eight flax genotypes (Indian, Polish, Syrian, Sakha 5, Sakha 6, Giza 8, Giza 10, and Giza 11). The results showed that the Sakha 5 cultivar was excelled in the number of leaves and leaf area, which reached (597.0 leaves.plant-1, 897.6 cm2), respectively, while the Syrian cultivar was excelled in the early flowering, which reached (90.88 days), while the Giza 10 cultivar was excelled in the activity of the peroxidase enzyme, which reached (55.94 absorption units g-1). The plants of the 11 cultivar were superior in the weight of 1000 seeds, seed yield, and oil percentage, which reached (11.39 g, 1228.2 kg ha-1, 56.228%), while the plants in the irrigation treatment (50% depletion of ready water) were excelled in the number of leaves, leaf area, weight of 1000 seeds, seed yield, and oil percentage, as follows (613.3 leaves.plant-1, 982.4 cm2.plant-1, 11.38 g). 1356.7 kg ha-1, 58.18%), respectively, compared to plants in the irrigation treatment (70% depletion of available water) and the irrigation treatment (90% depletion of available water).