ارزیابی واکنش ژنوتیپ‌های مختلف گندم نان نسبت به نماتد سیستی غلات (Heterodera Filipjevi) در شرایط گلخانه

نماتدهای سیستی غلات یکی از عوامل زنده تهدیدکننده تولید گندم مخصوصاً در شرایط دیم و استرس‌های ناشی از خشکی در بیشتر کشورهای تولیدکننده گندم در جهان به شمار می روند. از بین گونه‌های نماتد سیستی غلات، heterodera filipjevi  گونه غالب و شایع در مزارع غلات ایران است. در این مطالعه واکنش ژنوتیپ‌های رایج گندم نان شامل چندین رقم و لاین نسبت به h. filipjevi در شرایط گلخانه، برمبنای روش ارایه شده جهت غربالگری ژنوتیپ های گندم تحت شرایط کنترل شده، مورد ارزیابی قرار گرفت. نتایج نشان داد ارقام بک کراس روشن با میانگین جمعیت 2/30 و سیلور استار با میانگین جمعیت 8/6 سیست و ماده بالغ، به ترتیب بیشترین و کمترین میانگین جمعیت را به خود اختصاص دادند. تجزیه خوشه ای داده ها، کلیه ژنوتیپ ها را در چهار گروه تقسیم‌بندی نمود. سه رقم بک کراس روشن، پیشتاز و پیشگام با توجه به بالاتر بودن میانگین تعداد سیست‌های موجود در خاک و ریشه نسبت به رقم حساس بزوستایا (شاهد حساس) به عنوان ژنوتیپ های بسیار حساس (hs) گروه بندی شدند. ارقام مهدوی، بم، دنا، بهار، سیوند، افق، ارگ و بزوستایا در گروه ژنوتیپ های حساس (s) قرار گرفتند. ژنوتیپ های روشن، الوند، پارسی، es9395 و مرودشت به عنوان ژنوتیپ های نسبتاً حساس (ms) و ژنوتیپ های سیروان، m909 و m907 به همراه ژنوتیپ سیلور استار (شاهد نسبتاً مقاوم)، در گروه ژنوتیپ های نسبتاً مقاوم (mr) قرار گرفتند.

Assessment of reaction to Cereal cyst nematodes (Heterodear filipjevi) to different bread wheat accessions under greenhouse conditions

Background and Objectives Cereal cyst nematodes (CCNs) are acknowledged globally as a biotic constraint for wheat production, particularly under rainfed conditions and drought stress. Among species of CCNs, Heterodear filipjevi is the dominant species in most cereal growing areas of Iran and is widespread in different regions of the country. The use of resistant wheat cultivars is considered the most effective and economical method for managing cereal cyst nematodes. The effectiveness of resistance to CCNs depends on the efficiency and durability of the sources of resistance, and on the correct identification of the nematode species and pathotype(s) present in each region. The objective of this study was to assess the reaction of common accessions of bread wheat to H. filipjevi under greenhouse conditions. Materials and Methods The reaction of common accessions of bread wheat, including some cultivars and lines (20 accessions) to H. filipjevi was assessed according to used method for screening of wheat accessions under controlled conditions. Single wheat seeds were planted in standard small tubes. After plant emergence, tubes were inoculated with 300 freshly hatched J2 in 3 holes around the stem base. Experimental units were arranged in a randomized complete block design with 5 replicates. Plants were harvested 8 weeks after juvenile inoculation. Extracted Cysts from both root and soil counted under a stereomicroscope. The data were analyzed and the genotypes were divided into different groups based on their reactions. Results The results showed that Backcross Rowshan cultivar with mean 30.2 and Silverstar cultivar with mean 6.8 had the most and the least number of cysts in soil and root of each plant, respectively. Cluster analysis divided all accessions into 4 groups. Backcross Rowshan, Pishtaz and Pishgam cultivars were identified as highly susceptible according to higher mean of the cyst number in soil and root, in comparison to Bezostaya cultivar (Susceptible check). Mahdavi, Bam, Dena, Bahar, Sivand, Ofogh, Arg and Bezostaya cultivars were categorized as susceptible. Rowshan, Alvand, Parsi, Es9395 and Marvdasht accessions were grouped as moderately susceptible, and, Sirvan, M909, M907 and Silverstar (Moderately resistant check) accessions were identified as moderately resistant. Discussion This study revealed that Backcross Rowshan, Pishtaz and Pishgam are highly susceptible cultivars to H. filipjevi. However, the cultivation of these wheat cultivars is common in the country. In order to impeding the damage of this nematode, it is essential to avoid cultivating these cultivars and other susceptible cultivars in infested fields to H. filipjevi.