نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه آگروتکنولوژی، دانشکده کشاورزی، دانشگاه فردوسی مشهد
2 دانشگاه فردوسی مشهد- گروه اگروتکنولوژی
3 دانشگاه فردوسی مشهد گروه اگروتکنولوژی
4 3- دانشیار، موسسه تحقیقات اصلاح و تهیه بذر چغندر قند، کرج، ایران
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
Severe freezing in winter and early spring may influence the growth and survival of wheat (Triticum aestvum L.) and decrease its yield. These experiment was carried out to explore freezing tolerance of two wheat cultivars under controlled and field conditions. Both experiments conducted as a split-split plots based on a completely randomized design with three replications. The main plots in green house were six freezing temperatures (zero,-4, -8, -12, -16, and -20°C), the sub-plots were three paclobutrazol (PBZ) concentrations (foliar application of zero as control, 30 and 60 mg L-1) and the sub-sub-plots were wheat cultivars (‘Mihan’ and ‘Pishtaz’). In the field main plots were three sowing date (16th Oct., 13th Nov. and 5th Dec.), and the sub and sub-sub-plots were the same as controlled experiment. The results showed that, with a reduction of temperature from zero to -20°C, the electrolyte leakage of membrane increased significantly by 71.5%. The electrolyte leakage in cv. ‘Mihan’ significantly lower than that of cv. ‘Pishtaz’ when freezing temperature was decreased lower than -16°C. PBZ also caused shorter plants but less leaf lost due to freezing stress in both cultivars. Delay in sowing date from 16th Oct. to 13th Nov. and 5th of Dec. caused 19 and 31% seed yield reduction in wheat cultivars, respectively, while seed yield of Mihan was 17% higher than pishtaz. Based on our results, Mihan cultivar has higher freezing tolerance capacity and in temperature below -12°C and PBZ application can alleviate negative effects of freezing stress in this wheat cultivar.
کلیدواژه‌ها [English]
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