ارزیابی مقاومت لاین‌های امیدبخش گندم نسبت به خسارت سن (eurygaster integriceps) در شرایط آب و هوایی نیشابور

سن گندم یکی از مهم‌ترین آفات در مزارع غلات بوده که سالانه خسارت کیفی و کمی جبران ناپذیری به گندم و جو وارد می‌کند. این پژوهش به‌منظور بررسی مقاومت 20 لاین امیدبخش گندم نسبت به آفت سن، در قالب طرح بلوک‌های کامل تصادفی با سه تکرار در ایستگاه تحقیقات و آموزش کشاورزی و منابع طبیعی شهرستان نیشابور در سال زراعی 1402-1401 انجام شد. تیمارها شامل 18 لاین بهاره گندم حاصل برنامه‌های به‌نژادی موسسه تحقیقات اصلاح و تهیه نهال و بذر و دو رقم امین و فرین به‌عنوان شاهد بودند. نتایج تجزیه واریانس آماری داده‌های آزمایش نشان داد که بین لاین‌های مورد مطالعه از نظر صفات مورد بررسی شامل تراکم پوره و حشرات کامل نسل جدید، درصد خسارت سن‌زدگی دانه، خسارت برگی، ارتفاع بوته، وزن هزار دانه، درصد گلوتن دانه، درصد نیتروژن دانه و عملکرد دانه گندم از نظر آماری تفاوت معنی‌داری وجود داشت. درصد خسارت سن‌زدگی دانه در رقم امین و لاین 15 حداکثر و در رقم فرین و لاین های 19 و 10 حداقل مقدار بود. بیشترین خسارت برگی در لاین 19 و کمترین در لاین 6 مشاهده شد. لاین های 15و 20 به‌ترتیب بیشترین و کمترین وزن هزار دانه را به خود اختصاص دادند. بیشترین درصد گلوتن مربوط به لاین 15 بود و کمترین میزان به لاین 9 اختصاص یافت. بیشترین درصد نیتروژن برای لاین 15 و کمترین میزان برای رقم امین مشاهده شد. از نظر عملکرد دانه، لاین 6 حداکثر و رقم امین و لاین 20 حداقل میزان این صفت را داشتند. ارزیابی همبستگی بین صفات مورد مطالعه نشان داد که میزان خسارت برگی با عملکرد دانه همبستگی منفی و معنی‌داری داشت. ارتفاع بوته با عملکرد دانه، وزن 1000 دانه با درصد نیتروژن دانه، وزن 1000 دانه با درصد گلوتن دانه، عملکرد دانه با درصد گلوتن دانه، عملکرد دانه با درصد نیتروژن دانه و نیز درصد گلوتن دانه با درصد نیتروژن دانه همبستگی مثبت و معنی‌داری داشت. لاین 6 با کمترین خسارت برگی و بیشترین درصد گلوتن و عملکرد دانه به‌عنوان متحمل لاین به سن و رقم امین با بیشترین میزان سن‌زدگی، کمترین درصد گلوتن، وزن هزار دانه و عملکرد دانه به‌عنوان لاین حساس به سن شناسایی شدند.

evaluation of resistance of wheat promising lines to eurygaster integriceps in neyshabur climatic conditions

introductionthe sunn pest (eurygaster integriceps put) is a significant pest of wheat in turkey, west and central asia, and iran. damage caused by this pest to leaves, stems, spikes, and grains can reduce the baking quality of flour made from affected grains of cereals. sunn pest adults typically overwinter in mountainous areas under plants such as oak, wild liquorice, and echinacea, migrating to wheat fields when temperatures warm up in spring. their feeding behavior involves piercing and cutting tissues, as well as injecting digestive enzymes through a salivary canal to predigest food.wheat is a major crop, covering vast areas of agricultural land worldwide. the pest causes significant damage to grain crops, particularly wheat (iranipour et al., 2010). among these pests, the sunn pest stands out as the most devastating insect (el bouhssini et al., 2013). high-quality bread wheat genotypes have shown to be less susceptible to the effects of bug proteinase in baking compared to poor-quality wheat varieties. chemical control of sunn pest is not only costly but also hazardous to human health and the environment, and has adverse effects on natural predators (krupnov, 2012). identifying resistant cultivars could serve as an effective integrated pest management (ipm) strategy, reducing the need for chemical applications. the use of resistant cultivars is both an effective and cost-efficient method for protecting wheat crops from this insect pest while minimizing pesticide use.therefore, the widespread and rampant spread of this pest highlights the urgent need to identify and use non-chemical control methods, especially the selection of resistant varieties. this study aimed to assess the agronomic characteristics and quality of wheat lines to sunn pest under neyshabur climatic conditions.materials and methodsthis research was conducted during the growing season in 2022-2023 at agricultural and natural resources research and education center of neyshabur, based on a randomized complete block design with three replications. treatment was 20 lines/cultivars, including 18 promising lines, along with two cultivars of amin and farin as control. the studied traits included density of overwintered adults (owas), density of of nymphs and new-generation adults (ngas), seed damage percentage, density of whitish spikes, leaf damage level, plant height, 1000-kernel weight, gluten and nitrogen contents of kernel and grain yield. the counting of damaged plants was done at the flowering stage using quadrats (0.5×0.5 m2). pearson’s correlation was calculated to evaluate the correlation between all quantitative traits and quality of wheat lines. statistical analysis of data was performed using minitab software, and figures were plotted using excel software. means were compared using the lsd test at the 5% and 1% probability levels. results and discussionthe results of the statistical analysis indicated a significant difference among the studied lines in terms of the examined traits, including density of ngas, seed damage percentage, leaf damage level, plant height, 1000-kernel weight, gluten content of kernel, nitrogen content of kernel and grain yield. the density of owas was not significantly impacted by the wheat lines, so line 18 (with 1.33 numbers per m2) and line 20 (without owas) had the highest and lowest owas, respectively. the maximum damage percentage was observed in amin cultivar (6%) and line 15 (5.6%), while the minimum level was recorded for farin cultivar (0.53%) and lines 19 and 10 (1.06%). line 19 had the highest leaf damage (11.11 leves.m-2), while line 6 had the lowest (1 leves.m-2). line 8 had the highest plant height (99 cm), while line 20 had the lowest (83 cm). lines 15 (44.57 g) and 20 (35.16 g) had the highest and lowest 1000-kernel weight, respectively. the highest percentage of kernel gluten was found in line 15 (27.05%), while the lowest was found in line 9 (24.2%). line 15 also had the highest percentage of kernel nitrogen (2.35%), while the amin cultivar had the lowest (1.97%). line 6 had the highest grain yield (6.08 t.ha-1), while amin cultivar (4.31 t.ha-1) and line 20 (4.33) had the lowest grain yield. the correlation analysis between the studied traits showed that leaf damage level had a significant negative correlation with grain yield (r=0.57**). plant height showed a significant positive correlation with grain yield (r=0.45*), 1000-kernel weight had a significant positive correlation with nitrogen content of kernel (r=0.70**), and grain yield had a significant positive correlation with nitrogen content of kernel (r=0.62**). the damage percentage had a significant negative correlation with leaf damage level (r=0.04ns), plant height (r=0.13ns), grain yield (r=0.57**), and grain nitrogen percentage (r=0.05ns).conclusionin neyshabur county, line 6 exhibited the highest tolerance to sunn pest and produced the highest grain yield compared to other lines. on the other hand, amin cultivar was sensitive to sunn pest and had a lower 1000-kernel weight and grain yield.