ارزيابي تحمل به يخ زدگي در ارقام گندم (.Triticum aestivum L) تحت شرايط كنترل شده

Evaluation of cold tolerance in wheat {Triticum aestivum L.) cultivars under controlled conditions

In order to determine freezing tolerance of 14 wheat cultivars including Anza, Bezostaja, Pishtaz, Tous, Zagros, Zarrin, Shahryar, Falat, Qods, Glenson, Maron, Navid, Niknejad and MV-17 that were grown on field, samples of each cultivar after hardening in the field were harvested in 4-6 leave stages and trimmed to 2cm above and below the crowns and put on the thermogradient freezer. After freezing in the range of 0 to -20 °C, samples were transferred to the greenhouse and planted in the pots. Survival percentage, height, leaf area, chlorophyll content, dry weight, LT5o and DMT50 were determined after 3 weeks. Survival percentage after freezing was different in cultivars (P<0.05). Glenson and Maron cultivars had the highest (72.2%) and the lowest (24.4%) survival, respectively. Cultivars were different in height, leaf area, chlorophyll content, dry weight, LT50 and DMT50. Glenson was the most cold tolerant cultivar (LT50=-15.8 °C) and Maron was the most sensitive cultivar (LT50=-3.7 °C). Conducting further experiments in controlled and field conditions and study of correlations, leads to more reliable results from controlled experiments.