ارزیابی صفات مختلف برخی ژنوتیپ‌های لوبیا (phaseolus vulgaris l.) در شرایط آب‌وهوایی ایلام

با توجه به اهمیت اقتصادی خسارت کنه‌ها، به‌ویژه کنه تارتن دولکه‌ای و کمبود مطالعات در این زمینه، بررسی مقاومت ژنتیکی ارقام لوبیا (phaseolus vulgaris l.) به این آفت و شناسایی ارقام متحمل، امری ضروری به نظر می‌رسد. در این پژوهش، 25 ژنوتیپ لوبیا شامل 10 رقم و 15 لاین در شرایط اقلیمی ایلام و در قالب طرح بلوک‌های کامل تصادفی با سه تکرار در مزرعه تحقیقاتی دانشکده کشاورزی دانشگاه ایلام مورد ارزیابی قرار گرفتند. عملیات کاشت در سال زراعی 1401–1400 و در تاریخ 3 خرداد 1400، که در بازه زمانی مطلوب کاشت (20 اردیبهشت تا 15 خرداد) قرار داشت، انجام شد. نخستین علائم آلودگی به کنه تارتن دولکه‌ای (tetranychus urticae koch) در مرحله آغاز گل‌دهی مشاهده گردید. برای سنجش تحمل ژنوتیپ‌ها، خسارت به برگ‌ها با مقیاس 0 تا 4 ارزیابی شد. صفات مورد مطالعه شامل طول و عرض غلاف، تعداد دانه در غلاف، ارتفاع بوته، تعداد غلاف و دانه در بوته، عملکرد دانه، میزان خسارت آفت، تعداد روز تا گل‌دهی و غلاف‌دهی بود. نتایج نشان داد که ژنوتیپ، تاثیر معنی‌داری بر تمامی صفات مورد مطالعه داشته است. ارقام اُفق و گلی در مقایسه با سایر ژنوتیپ‌ها، عملکرد دانه بالاتر و میزان خسارت کمتری در برابر آفت نشان دادند. تجزیه همبستگی نشان داد که بین تعداد دانه و غلاف در بوته، همبستگی مثبت و قوی (**0.87= r) و بین میزان خسارت و عملکرد دانه، همبستگی منفی و قوی (r = -0.78) وجود دارد. همچنین بر‌اساس ضریب همبستگی رتبه‌ای اسپیرمن، آلودگی با عملکرد دانه، تعداد غلاف در بوته، تعداد دانه در بوته و طول غلاف، همبستگی منفی و معنی‌دار دارد. تجزیه خوشه‌ای نیز ژنوتیپ‌ها را به چهار گروه حساس، نیمه‌حساس، متحمل و نیمه‌متحمل تقسیم‌بندی کرد. به‌کارگیری ژنوتیپ «گلی» با توجه به عملکرد برتر و تحمل آن به کنه، به‌عنوان رقمی مناسب برای کشت در این منطقه توصیه می‌شود.

evaluation of various traits of some bean (phaseolus vulgaris l.) genotypes in ilam climatic conditions

introduction common bean (phaseolus vulgaris l.) is a vital legume, rich in protein and nutrients, that is significantly impacted by the two-spotted spider mite (tetranychus urticae), leading to substantial economic losses in agricultural fields. given the limitations of chemical control and its environmental consequences, the identification and utilization of resistant cultivars represent a sustainable approach to pest management. various studies have demonstrated that certain bean genotypes possess morphological and physiological characteristics that effectively reduce mite populations. to date, a comprehensive assessment of bean genotype resistance to t. urticae under the climatic conditions of ilam province has not been conducted. this research aims to evaluate the resistance of 25 bean genotypes to this pest under field conditions in ilam, with the goal of identifying resistant varieties for integration into breeding programs and sustainable agricultural practices. materials and methodsthis research was conducted during the 2021-2022 growing season at the research farm of ilam university to identify resistant and high-yielding bean varieties against t. urticae. twenty-five bean genotypes (10 cultivars and 15 lines), including the susceptible cultivar akhtar, were obtained from the gene bank of tehran university and planted in a randomized complete block design (rcbd) with three replications. following spring plowing, planting was carried out in june 2021, and irrigation was performed using the flood irrigation method every 3 to 4 days. symptoms of infestation appeared during the flowering stage, and the extent of damage to the leaves was assessed using a five-point scale (0 = no infestation, 4 = severe damage). phenological traits (days to flowering and podding) and morphological traits (plant height, pod length and width, number of seeds and pods) were measured, and the yield of each genotype was calculated based on the total weight of the seeds. results and discussion the results of this research indicated that there was considerable genetic diversity for all of the traits that were investigated. based on the results of analysis of variance, the results of analysis of variance showed that there was a significant difference between genotypes in terms of all traits at the 1% level. genotypes goli and d81083 were identified as the most resistant and had the highest yield (101.5 g per plant), while genotype 288 showed the most susceptibility and the lowest yield (0.42 g per plant). cultivar goli had the highest number of pods (37.7 per plant), and cultivar 323 had the lowest number of pods (2.67 per plant). additionally, cultivar goli had the highest number of seeds per pod (5.1), and cultivar local azna had the lowest number of seeds per pod (1.8). in terms of plant height, cultivar 1090 had the tallest plants at 122.7 cm, and cultivar khomein had the shortest plants at 36.1 cm. the greatest pod length (10.6 cm) was observed in cultivar derakhshan, and the shortest length (1.6 cm) in cultivar 79emerson. a significant negative correlation between mite damage and yield (r = -0.78) indicated that increased damage leads to lower yield. cluster analysis divided the genotypes into four groups, with genotypes goli and d81083 in the resistant group and genotypes 1090 and 288 in the susceptible group. these results confirm that the use of resistant genotypes can help reduce pest damage and increase yield. correlation analysis showed that the level of pest damage has a negative and significant correlation with yield and its components (r=-0.78).