تاثیر کم‌آبیاری بر عملکرد و صفات مرتبط با آن در ژنوتیپ‌های امیدبخش لوبیا چیتی (phaseolus vulgaris l.) در شرایط اقلیمی استان زنجان

جهت بررسی اثرات کم‌آبیاری بر برخی از صفات فنولوژیک و زراعی لوبیا چیتی و انتخاب ژنوتیپ‌های دارای عملکرد مطلوب در شرایط محدودیت آبی، 14 ژنوتیپ امیدبخش لوبیا چیتی حاصل از برنامه‌های اصلاحی در دو سال زراعی متوالی 1400 تا 1401 به همراه ارقام شاهد صدری و کوشا در ایستگاه تحقیقات خیرآباد زنجان در دو شرایط آبیاری نرمال (دور آبیاری پنج روز) و کم‌آبیاری (دور آبیاری نُه روز) مورد بررسی قرار گرفتند. بین دورهای آبیاری پنج و نه روز، در صفات تعداد بوته در کرت و تعداد غلاف در گیاه در سطح یک درصد و در صفات ارتفاع بوته و عملکرد در سطح پنج درصد و بین ژنوتیپ‌های مورد ارزیابی از نظر تمامی صفات مورد مطالعه (به‌جز تعداد بوته در کرت) اختلاف معنی‌داری در سطح احتمال یک درصد وجود داشت. دور آبیاری نُه روز باعث کاهش ارتفاع گیاه، عملکرد دانه، تعداد غلاف در بوته، تعداد دانه در غلاف و وزن 100 دانه شد. ژنوتیپ‌های g8، g10، g14 و g15 دارای بیشترین و ژنوتیپ‌های g13 و g2 دارای کمترین عملکرد بودند. تعداد غلاف در بوته، تعداد دانه در غلاف و وزن 100 دانه مهم‌ترین اجزاء موثر بر عملکرد دانه بودند و با توجیه میزان زیادی از تغییرات موجود در عملکرد، می‌توانند برای بهبود عملکرد لوبیا در برنامه‌های اصلاحی جهت شرایط مختلف محیطی قابل‌ توجه باشند. ژنوتیپ g8 با دارا بودن بیشترین تعداد غلاف در بوته و وزن 100 دانه بالا می‌تواند به‌عنوان ژنوتیپ مطلوب جهت کشت در شرایط نرمال و کم‌آبیاری معرفی شود.

the effect of deficit irrigation on yield and its related traits in promising chiti bean (phaseolus vulgaris l.) genotypes under zanjan province climatic condition

introductiongiven that successive droughts, particularly recent ones, have impacted most regions of iran, drought stress is recognized as one of the major challenges for crop production in the country’s arid and semi-arid regions. beans grow in a wide range of areas that are subject to seasonal droughts and wide fluctuations in soil moisture in different years. nevertheless, drought stress causes a significant decrease in bean seed yield, and the amount of yield decrease is different depending on the time, stress intensity and studied genotype. due to environmental conditions in areas where bean cultivation is common, water deficit may occur more than once during the crop growth cycle. in addition, when a dry period (two to three weeks) occurs, especially during flowering, yield reduction will be significant. drought-adapted cultivars in beans require less water for irrigation and thus help conserve water resources. despite the desire of farmers to maximize the use of irrigation to increase production in dry and semi-arid conditions, even in the absence of water restrictions, excessive irrigation is not logical; therefore, in such a situation, the efficiency of water consumption in the farm should be optimized. deficit irrigation is an optimization strategy that purposefully allows the plant to tolerate some degree of deficit irrigation and reduced yield. several studies show that lack of irrigation causes a significant decrease in the number of seeds, seed weight, number of fertile pods, number of seeds in pod, seed yield, biological yield and harvest index. of the two main components of seed yield (seed number and seed weight), seed number shows higher sensitivity to water deficit. in this regard, in this research, it has been tried to evaluate the effects of drought stress on yield and yield components in 16 genotypes and cultivars of chiti beans and determine the genotypes with optimal yield under water limitation conditions. materials and methodsin order to investigate the effects of deficit irrigation on some phenological and yield traits of chiti beans, 14 promising chiti bean genotypes obtained from breeding programs along with sadri and kosha control cultivars, in two consecutive crop years from 2022 to 2023, at kheirabad zanjan research station, in two conditions normal irrigation (irrigation cycle of 5 days) and deficit irrigation (irrigation cycle of 9 days) were investigated. the experiment was performed at both conditions and in both years, as basic of complete randomized blocks design with 3 replications. combined variance analysis and mean comparisons were performed and simple correlation coefficients between traits and stepwise regression analysis of traits affecting grain yield in both irrigation conditions were calculated. results and discussion variance analysis showed that there was a significant difference between the 5 and 9 day irrigation cycles in the number of plants per plot and the number of pods per plant at the 1% level, and in the plant height and yield at the 5% level. there was significant difference between genotypes in terms of all the studied traits (except the number of plants in plot) at the probability level of 1%. irrigation cycle of 9 days decreased plant height, seed yield and its components including number of pods per plant, number of seeds per pod and 100 seed weight. g8, g10, g14 and g15 genotypes had the highest and g13 and g2 genotypes had the lowest seed yield.