ارزیابی تحمل به غرقاب در برخی از ژنوتیپ‌های‌ کتان با استفاده از شاخص‌ نمره تحمل به تنش

کتان گیاهی علفی با نام علمی linum usitaissimum l.  است. منشا این گیاه غرب مدیترانه گزارش شده است. کتان ازجمله گیاهان مهم روغنی و دارویی با سازگاری وسیع و مصارف متعدد است. تنش غرقاب یکی از تنش‌های غیرزیستی است که باوجوداینکه در صورت بروز خسارت زیادی به محصول زراعی وارد می‌کند توجه کمی به آن شده است. برای غربالگری ژنوتیپ‌های مقاوم به تنش از شاخص‌های مختلفی استفاده شده است. هدف اصلی این مطالعه شناسایی ژنوتیپ‌های کتان مقاوم به تنش غرقاب با استفاده از همه شاخص‌ها به طور هم‌زمان و همچنین شناسایی ژنوتیپ‌های پربازده در شرایط تنش غرقاب و شرایط بدون تنش بود. در این پژوهش 100 رقم کتان موردمطالعه قرار گرفت. ارقام مذکور جهت بررسی تنوع ژنتیکی و انتخاب بهترین ارقام ازلحاظ عملکرد و سایر صفات مورفولوژیک در گلخانه‏ به‌صورت یک آزمایش فاکتوریل در قالب طرح بلوک کامل تصادفی کشت شدند. پس از رسیدن گیاه به مرحله چهار ‌برگی حقیقی، تنش غرقاب اعمال شد. به مدت دوهفته گلدان‌هایی که تحت تنش بودند تحت آبیاری بیش از ظرفیت مزرعه خاک بود. برخی شاخص­ها محاسبه شد و درنهایت به‌وسیله شاخص نمره تحمل به تنش (sts) ژنوتیپ‌های متحمل و حساس شناسایی شدند. شاخص‌های tol، sti، mp و gmp با عملکرد در شرایط نرمال و sti، mp، gmp، yi و dri با عملکرد در شرایط تنش غرقاب همبستگی مثبت و معناداری داشتند. بر طبق نمره تحمل به تنش ژنوتیپ‌های 364، 352، 286، 370 و 172 به‌عنوان ژنوتیپ‌های متحمل به تنش غرقاب در این مطالعه شناخته شدند و ژنوتیپ‌های 263، 269، 295، 325 و 108 حساس‌ترین ژنوتیپ‌ها بودند.

evaluation of flood tolerance in some flax genotypes using stress tolerance score index

introductionflax is a herbaceous plant with the scientific name of linum usitatissimum l. the origin of this plant is reported to be the western mediterranean. flax is one of the most important oily and medicinal plants with wide compatibility and multiple uses. waterlogging stress is one of the abiotic stresses that has received little attention despite the fact that it causes a lot of damage to the crop.materials and methodsin this study, 100 flax cultivars were studied. the mentioned cultivars were planted in a greenhouse as a factorial experiment in a randomized complete block design to investigate genetic diversity and select the best cultivars in terms of yield and other morphological traits. first, flax seeds were planted in drainage pots containing field soil and aerated sand in a ratio of 2:1. soil-related measurements including field capacity (fc) and soil electrical conductivity (ec) were performed. waterlogging stress was applied in four-leaf stage. for two weeks, the pots that were in normal condition were irrigated according to the field capacity of the soil and the pots that were under stress were irrigated more than the field capacity of the soil. the main purpose of this study was to identify waterlogging-resistant flax genotypes using all indices simultaneously and also to identify high-yield genotypes under waterlogging stress and non-stress conditions. mp, sti, gmp, yi, dri, ysi, ssi, tol and β indices were calculated and finally tolerant and sensitive genotypes were identified by stress tolerance score (sts) index. sts equation for the raw data is not accurate. all indices in sts equation were standardized according to equation 10. all calculations were performed using spss software version 22 and excel.results and discussionthere was a significant correlation between ys and yp. tol, sti, mp and gmp indices with positive and significant correlation with performance under normal conditions and sti, mp, gmp, yi and dri with performance under normal conditions. dendrogram was drawn based on stress tolerance score. flax genotypes were divided into 4 groups: resistant, semi-resistant, semi-susceptible and susceptible. analysis of variance was performed to determine the accuracy of grouping between groups and there was a significant difference between the groups. according to the stress tolerance score index, genotypes 364, 352, 286, 370 and 172 were identified as waterlogging tolerant genotypes in this study and genotypes 263, 269, 295, 325 and 108 were the most sensitive genotypes. according to the stress tolerance score index, genotypes 364, 352, 286, 370 and 172 were submerged as stress tolerant genotypes. these genotypes are predicted to be used as donors of waterlogging tolerance genes. research findings also indicate that tolerant genotypes ultimately lead to higher production and yields than other genotypes in conditions of heavy rainfall and prolonged waterlogging. these genotypes can also be used in breeding programs based on hybridization and identification of qtls associated with waterlogging tolerance.conclusionsthey were overwhelmed by tension. according to the stress tolerance score, genotypes 364, 352, 286, 370 and 172 were identified as flood tolerant genotypes in this study and genotypes 263, 269, 295, 325 and 108 were the most sensitive genotypes.