This experiment was carried out in a Zn-deficient calcareous soil to study the effects of Zn deficiency on shoot dry weight, shoot content, and concentration of Zn, and also to identify new sources of Zn efficiency for further improvement of Zn efficiency with (+Zn = application of 5 mg Zn/kg soil) and without Zn supply (-Zn = non-application of zinc) on 50 durum wheat genotypes for 45 days. Variance analysis for shoot dry matter, shoot Zn concentration, shoot Zn content, and Zn utilization efficiency revealed that these traits were significantly (P< 0.01) affected by Zn application and durum wheat genotypes. Results revealed that dry weight of shoot and shoot Zn accumulation were considerably improved by Zn fertilizers. Furthermore, there was a considerable genetic variation in the expression of Zn deficiency symptoms (slight to severe), Zn efficiency (49-100%), shoot Zn concentration (7.1-20.1 and 10.4-33.1 mg Zn/kg dry weight under Zn deficient and sufficient, respectively), shoot Zn content (0.31-1.47 and 0.7-2.9 µg/plant under Zn deficient and sufficient, respectively), and Zn utilizationefficiency (59.2-139.1 and 34.3-94.0 g dry weight/µg Zn under Zn deficient and sufficient, respectively) within durum wheat genotypes.In general, the presence of lines (AAZ, 4025, 45868, 45558 and Azarbayjan) with greater Zn efficiency than Zn efficient durum wheat cultivars (Ege-88, Aydin-93 and Akcakale-2000) indicates that the new lines can be used to improve current levels of Zn efficiency in durum wheat genotypes. Manuscript profile

خشکی و کمبود عنصر آهن در خاک‌های زراعی محدودیت عمده‌ای در تولید غلات از جمله جو تحت شرایط دیم بوده که باعث کاهش عملکرد و کیفیت محصول می‌گردد. به منظور ارزیابی تنوع ژنتیکی در بین ژنوتیپ‌های جو برای کارایی جذب روی، غلظت و میزان روی در بذر؛ همچنین بررسی ارتباط بین محتوی و غلظت آهن در بذر با عملکرد ژنوتیپ‌ها، تعداد 121 ژنوتیپ جو در طی سال‌های زراعی 1395 – 1394در مزرعه تحقیقاتی موسسه تحقیقات کشاورزی دیم کشور اجرا شد. مشتمل بر ژنوتیپ‌های جو دریافتی از بانک ژن تحت شرایط مزرعه‌ای بررسی شدند. آزمایش در قالب طرح لاتیس مربع با دو تکرار اجرا شد. بر اساس نتایج تجزیه واریانس، بین ژنوتیپ‌ها برای صفات غلظت و محتوی آهن در بذر اختلاف آماری معنی‌دار وجود داشت. ضمنا دامنه تغییرات این صفات بسیار زیاد بود که نشانگر وجود تنوع ژنتیکی بسیار خوب بین ژنوتیپ‌ها می‌باشد. با توجه به میزان بالای وراثت‌پذیری عمومی صفات غلظت و محتوای آهن در بذر، می‌توان گفت که اصلاح برای این صفات موثر بوده و می‌توانند در محیط‌های مختلف پایداری را نیز نشان دهند. با توجه به همبستگی مثبت و بالا ما بین غلظت و محتوای آهن در بذر (**63/0r =)، عموما ژنوتیپ‌هایی با غلظت آهن بیشتر، از محتوای آهن بالاتری نیز برخوردار بودند. در کل نتایج این تحقیق، ضمن آشکار کردن وجود تنوع ژنتیکی برای جذب و تجمع آهن در بین ژنوتیپ‌های جو، نشان داد ژنوتیپ‌های کارا در جذب و تجمع آهن در بذر می‌توانند با تعدیل اثرات تنش خشکی موجب افزایش عملکرد دانه تحت شرایط دیم گردند. Manuscript profile

Abstract Micronutrients deficiency stress is one of the most important dangers for increasing the yield and good production of crops in the world. In order to evaluate genetic diversity of nineteen durum wheat (Triticum turgidum var durum) genotypes to identify the most zinc-deficient stress resistant genotypes and also finding the best stress tolerance indices, an experiment was carried out in the University of Maragheh, Iran during cropping season of 2014 by using a factorial design in the randomized complete block design (RCBD) with three replications. The experiment was done zinc deficient stress (non-Zn application; -Zn) and normal soil application (5 mg Zn/kg soil + foliar application with 0.44 g Zn/liter water at stem elongation and grain filling stages; +Zn) conditions. Results indicated that Zn conditions as well as, wheat genotypes differed significantly for all studied agro-morphological traits in both normal and Zn deficient stress conditions. Our findings indicated that Zn-deficient stress significantly decreased the spike length (SL), peduncle length (PedL), penultimate length (PenL), plant height (PH), spike weight (SW), peduncle weight (PedW), penultimate weight (PenW), biological yield (BY), grain yield (GY), harvest index (HI), number of grains per spike (NGS), number of fertile spikelet per spike (FS) and 1000 grains weight (TGW) by 14, 10.6, 10.4, 12.5, 25.3, 26.2, 27.9, 27.5, 29.4, 5.0, 25.5, 17.7 and 5.4%, respectively. Among durum wheat genotypes, ‘G2’ had the highest and also ‘G10’ and ‘G19’ had the lowest SW, PedW, BY and FS, respectively; while the highest and the shortest GY and NGS was observed in ‘G17’ (0.763 g/plant and 23.2 grain) and ‘G10’ and ‘G19’ (0.372 and 367 g/plant and 8.9 and 9.5 grain) genotypes, respectively. This indicating the presence of variability, which can be exploited through selection for further breeding programs. According to results of stress tolerance indices, ‘G17’, ‘G16’ and ‘G3’ genotypes have higher GY and STI index than other genotypes in two Zn conditions and identified as suitable genotypes for production in Zn deficient stress condition. Key words: Agro-morphological traits; Breeding; Calcareous soil; Durum wheat; Genetic variability; Zinc deficit. Manuscript profile