عملکرد، اجزاء عملکرد دانه و تبادلات گازی ارقام جو زراعی (hordeum vulgare l.) تحت کاربرد منابع مختلف کودی در شرایط دیم

استفاده کودهای زیستی از طریق بهبود خصوصیات فیزیکی و افزایش حاصلخیزی خاک و افزایش قابلیت دسترسی عناصر غذایی قابل جذب توسط گیاه، سبب بهبود رشد گیاه میزبان می گردد. قارچ میکوریزا به‌عنوان یکی از مهم‌ترین ریزموجودات زنده موجود در خاک، بر جذب عناصر غذایی از جمله فسفر، جذب آب در شرایط کم آبی، تعدیل تنش های محیطی، بهبود رشد ریشه و تاثیر بر رشد و عملکرد دانه می تواند موثر می باشد، به همین منظور آزمایشی مزرعه ای جهت بررسی اثر منابع کودی بر عملکرد دانه و تبادلات گازی ارقام جو (hordeum vulgare l.) در شرایط دیم، به‌صورت فاکتوریل در قالب طرح بلوک های کامل تصادفی با سه تکرار در مزرعه ایستگاه تحقیقات کشاورزی سرابله در سال زراعی 99- 1398 اجرا شد. تیمار های آزمایشی شامل ارقام جو (توده محلی، ماهور، خرم و فردان و منابع کودی شامل شاهد (عدم مصرف منبع کودی)، 50 درصد کود شیمیایی فسفر توصیه شده، قارچ میکوریزا (glomus mosseae، glomus etunicatum و rhizophagus irregularis)، قارچ میکوریزا + 50 درصد کود شیمیایی فسفر توصیه شده و 100 درصد کود شیمیایی فسفر بودند. نتایج این پژوهش نشان داد که برهم‌کنش رقم × منابع کودی بر عملکرد، اجزاء عملکرد دانه و تبادلات گازی در ارقام مختلف جو دیم معنی دار بود. براساس نتایج به‌دست آمده، بیشترین عملکرد، اجزاء عملکرد دانه، عملکرد زیست‌توده، میزان فتوسنتز، سرعت تعرق، هدایت مزوفیلی و کارآیی مصرف آب فتوسنتزی در جو رقم فردان × قارچ میکوریزا + 50 درصد کود شیمیایی فسفر به‌دست آمد و کمترین میزان عملکرد و اجزاء عملکرد و همچنین میزان فتوسنتز، سرعت تعرق، هدایت مزوفیلی و کارآیی مصرف آب فتوسنتزی در توده محلی × شاهد (عدم مصرف منبع کودی) مشاهده شد. بنابراین، با توجه به نتایج این پژوهش رقم جو فردان × کاربرد قارچ میکوریزا به‌واسطه افزایش میزان فتوسنتز و کارآیی مصرف آب فتوسنتزی و همچنین کاهش دمای برگ موجب افزایش قابل توجه عملکرد و اجزاء عملکرد دانه شد.

yield, yield components, and gas exchange in barley (hordeum vulgare l.) cultivars affected by the applications of different sources of fertilizer under dryland farming

introductionrainfed farming plays an important role in the food production of many countries in the semi-arid regions of the world and includes 80% of the total usable agricultural land. barley is cultivated in most parts of the world in areas that are threatened by moisture stress, the lack of which affects different stages of plant growth from germination to seed set, and finally affects the grain yield. studies show that the stress caused by the lack of water in plants is one of the important factors in crop reduction in semi-arid regions. application of biofertilizers improves yield by improving the physical properties of the soil, increasing soil fertility, and increasing the availability of nutrients for plant uptake, among which mycorrhizal fungi are considered the most important microorganisms. mycorrhizal fungi are effective in nutrient uptake, including phosphorus, water uptake in dehydrated conditions, hormone production, modulation of environmental stresses, improvement of root growth, and effect on soil granulation. since not much research has been done on the application of mycorrhizal fungi on dryland barley in the country and especially in ilam province, the present experiment was conducted to investigate the effect of mycorrhizal fungi on yield, yield components, and gas exchanges of dryland barley. materials and methodsin order to investigate the effect of mycorrhiza inoculation on yield and yield components and gas exchange of barley cultivars under rainfed conditions, a field experiment was carried out in factorial analysis based on a randomized complete block design with three replications at the farm of sarablah agricultural research center station during the 2019-2020 cropping season. experimental treatments include barley cultivars (mahali, mahour, khorram, and fardan) and fertilizer sources treatment, including control (no fertilizer source), 50% phosphorus fertilizer, mycorrhizal fungi (glomus mosseae, glomus etunicatum, and rhizophagus irregularis), and mycorrhizal fungi were +50% phosphorus fertilizer and 100% phosphorus fertilizers. in this study, the length of each plot was four meters, the number of rows in each plot was eight rows, and the distance between the rows was 20 cm. the measured traits were: yield and yield components, as well as gas exchanges, including photosynthetic rate, transpiration rate, photosynthetic water consumption efficiency, mesophilic conductance, co2, and leaf temperature. the effect of the treatments on yield and yield components and gas exchange of the barley cultivars in the field was assessed using sas; software, means were compared by duncan’s multiple range test method, and graphs were drawn using excel software.results and discussionthe results of this study showed that the interaction of cultivar×fertilizer sources on yield, grain yield components, as well as gas exchange characteristics, including photosynthetic mesoton, transpiration rate, photosynthetic water consumption efficiency, mesophilic conductance, substomatal carbon dioxide concentration, and leaf temperature in rainfed barley was significant. so that the maximum number of seeds per spike (32.3 seeds), 1000-grain weight (38.5 g), grain yield (4238.3 kg/ha), biomass yield (10123.3 kg/ha), photosynthesis rate (5.7 µmol co2 m-2s-1), transpiration rate (4 mmol h2o m-2s-1), mesophilic conductivity (0.019 mmol co2 m-2s-1) and water use efficiency photosynthesis (µmol co2 mol-1h2o) was obtained in fardan cultivar ×mycorrhiza+50% of phosphorus fertilizer compared to the control (no fertilizer source was used). conclusion    the results of this study showed that under rainfed conditions, yield and yield components, photosynthesis rate, transpiration rate, mesophilic conductance, and photosynthetic water use efficiency in all cultivars of barley were significantly reduced. however, the use of mycorrhizal fungi in dryland conditions improved grain yield and gas exchanges. in this study, barley fardan×application of mycorrhizal fungi caused a significant increase in yield and grain yield components by increasing photosynthesis and increasing photosynthetic water use efficiency, as well as decreasing leaf temperature.