ارزیابی واکنش ژنوتیپ های جو مربوط به آزمایشات مقایسه عملکرد مقدماتی، پیشرفته و امیدبخش سال زراعی ‮‭82-83‬ نسبت به بیماری زنگ زرد جو

Stripe (yellow) rust of barley is primarily a disease of cool climates. Such as, it is confined to barley grown at high elevations or over the winter. In Iran barley yellow rust is increasing in Northwest and Northern Provinces (e.g. Ardabil, Gorgan and Mashhad). In order to preventing of disease epidemic and decreasing of yield loss, use and production of resistant lines will be the best control method. Thus, for this purpose 600 barley genotypes of preliminary, Advanced and Elite Yield Trials (particularly for cold, hot and moderate areas) in three parts of country including Ardabil, Mashhad and Gorgam were evaluated in 2003 2004 cropping season. Each entry was planted in 2 rows of 1 length (rod row design), and experiment conducted under natural condition with artificial inoculation. For disease developing mist and flooding irrigation were used. At adult plant stage, infection type (IT) of each entry was evaluated based on Roelfs et al, method, when disease developed well on susceptible check (80- 100S). The percentage leaf area affected (disease severity) was also scored using the modified Cobb's scale at the same time. Then, coefficients of infection (CI) were calculated by combination of IT and disease severity. In this study was concluded that for Ardabil entries, 31.5% of genotypes were resistant (CI=0-2), 26.9% moderately resistant (CI = 3-4), 16.3% moderately susceptible (CI= 5- 12), 25.1% susceptible (CI> 12) and for Mashhad entries, 65.1% of genotypes were resistant, 7.8% moderately resistant, 7.4% moderately susceptible and 19.6% susceptible. Finally 74.9% of Ardabil entries and 80.4% of Mashhad entries were selected that had CI<16. Resistant lines or cultivars were introduced to SPII so that another evaluations can be conducted in future. Unfavorable weather condition caused that disease was not develop well in Gorgan. Key words: Barley, Yellow Rust and Resistance Evaluation.

Keywords:

جو , زنگ زرد , مقایسه عملکرد مقدماتی , مقایسه عملکرد پیشرفته , مقایسه عملکرد امیدبخش , مناطق سردسیر , اردبیل , مشهد , گرگان , آلودگی مصنوعی , آبیاری افشانه , آبیاری غرقابی