بررسی پارامترهای فتوسنتزی و عملکردی و ارتباط بین آن‌ها در ژنوتیپ‌های عدس در شرایط دیم

به‌منظور بررسی پارامترهای فتوسنتزی و عملکردی گیاه عدس در شرایط دیم، لاین های منتخب عدس به همراه ارقام شاهد در قالب طرح بلوک های کامل تصادفی با سه تکرار در ایستگاه تحقیقات دیم خدابنده استان زنجان در دو فصل زراعی 98-1397 و 99-1398 مورد بررسی قرار گرفتند. نتایج نشان داد که تفاوت معنی‌داری در صفات تابش فعال فتوسنتزی، دمای برگ، کارآیی مصرف آب فتوسنتزی، هدایت مزوفیلی، کارآیی مصرف آب، وزن100دانه و عملکرد بین دو سال اجرای آزمایش وجود دارد. ژنوتیپ‌های مورد مطالعه در صفات دمای برگ، میزان فتوسنتز، ارتفاع گیاه، وزن100دانه و عملکرد اختلاف معنی‌داری را با یکدیگر نشان دادند که حاکی از تنوع بالای ژنتیکی این ژنوتیپ‌ها از لحاظ این صفات بود. در بین ژنوتیپ‌های مورد مطالعه ژنوتیپ g5، ژنوتیپی با ویژگی‌های برتر زراعی بود که جهت معرفی به عنوان رقم با پتانسیل عملکرد بالا قابل بررسی می‌باشد. میزان فتوسنتز با دمای برگ همبستگی منفی معنی‌دار و با صفات میزان تعرق، هدایت روزنه‌ای، هدایت مزوفیلی، کارآیی مصرف آب و وزن100دانه همبستگی مثبت معنی‌دار نشان داد. در نهایت، تجزیه رگرسیون نشان داد که دو صفت هدایت روزنه‌ای و غلظت co2 زیر روزنه‌ای تبیین‌کننده تغییرات میزان فتوسنتز بودند.

investigation of photosynthetic and yield traits and the relationship between them in lentil genotypes under rainfed conditions

inroduction considering the development of cultivation and production of legumes and the importance of genetic studies in plant breeding, identifying the genetic potential of these plants is very important. knowledge of genetic diversity and relationships between genotypes is important for understanding available genetic variability and the potential to use it in breeding programs. according to previous studies on lentils, it was found that improving the yield potential per unit area can be one of the important criteria for increasing the production of this plant. increasing the yield per unit area is possible mainly by modifying and creating high-yielding cultivars, improving the characteristics and increasing the quantitative and qualitative potentials. breeders and plant physiologists believe that in order to be more productive in improving compatible cultivars in areas with limited water resources, recognizing the agronomic traits affecting grain yield under stress conditions will be of great importance; therefore, indirect selection based on physiological traits has been proposed as a complement to the selection of cultivars with high yield potential. considering the different reactions of photosynthetic indices under stress conditions, it is important to know the genotypic diversity of photosynthetic indices under culture conditions and their relationship with grain yield. despite numerous studies on the role of physiological traits in drought tolerance in crops, recent studies on lentils, especially in iran, are limited. this study was designed and carried out with the aim of determining genotypes with desirable physiological and yield traits and the relationship between these traits and photosynthesis under rainfed conditions. materials & methods in order to study the photosynthetic and yield parameters of lentil plant in rainfed conditions, selected advanced lentil lines with control cultivars were studied in a randomized complete block design with 3 replications in khodabandeh dryland research station in zanjan province in two cropping seasons 2018 to 2020. physiological traits included photosynthesis per unit leaf area, stomatal conductance, transpiration rate, photosynthetic activated radiation, sub stumatal co2, leaf temperature, photosynthetic water use efficiency, mesophilic conductivity and water use efficiency. plant height, 100-seed weight, number of pods and yield (kg/ha) were also measured for each genotype in each plot. analysis of variance and comparison of means were performed using duncan's test at 5% probability level. finally, correlation analysis and stepwise regression analysis were performed with the variables of photosynthesis rate and total yield. results & discussion the results showed that there was a significant difference in photosynthetic active radiation, leaf temperature, photosynthetic water use efficiency, mesophilic conductivity, water use efficiency, 100-grain weight and yield between two years of experiment. the studied genotypes showed significant differences in leaf temperature, photosynthesis, plant height, 100-seed weight and yield, which indicated the high genetic diversity of these genotypes in terms of these traits. the interaction effect of genotype per year was not significant in all studied traits, which shows that the trend of changes in these traits between genotypes during the two years was the same. among the studied genotypes, g5 genotype is a genotype with superior agronomic characteristics that can be recommended as a cultivar with high yield potential. photosynthesis rate showed a significant negative correlation with leaf temperature and significant positive correlation with transpiration rate, stomatal conductance, mesophilic conductivity, water use efficiency and 100-grain weight. 100-seed weight showed a significant negative correlation with leaf temperature and a significant