موسسه تحقیقات اصلاح و تهیه نهال و بذر نهال و بذر 1562-5494 40 3 2024 12 07 Employing Bayesian Probabilistic Approach for Risk Assessment in Selection and Recommendation of New Maize (Zea mays L.) Hybrids استفاده از رویکرد احتمالات بیزی برای ارزیابی ریسک در انتخاب و توصیه هیبریدهای جدید ذرت (.Zea mays L) 320 295 133365 10.22092/spj.2025.368724.1410 FA محمدرضا شیری دانشیار، بخش تحقیقات ذرت و گیاهان علوفه‌ای، موسسه تحقیقات اصلاح و تهیه نهال و بذر، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران. افشار استخر استادیار، بخش تحقیقات علوم زراعی و باغی، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی فارس، سازمان تحقیقات، آموزش و ترویج کشاورزی، شیراز، ایران. حمید نجفی نژاد دانشیار، بخش تحقیقات علوم زراعی و باغی، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی کرمان، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرمان، ایران. هادی حسن زاده مقدم استادیار، بخش تحقیقات علوم زراعی و باغی، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی خراسان رضوی، سازمان تحقیقات، آموزش و ترویج کشاورزی، مشهد، ایران علی شیرخانی استادیار، بخش تحقیقات علوم زراعی و باغی، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی کرمانشاه، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرمانشاه، ایران. رضا عطایی استادیار، بخش تحقیقات ذرت و گیاهان علوفه‌ای، موسسه تحقیقات اصلاح و تهیه نهال و بذر، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران. Journal Article 2024 11 05 Multi-environments trails are crucial elements in development and recommendation of new crop cultivars. Crop yield is influenced by genetic, environmental, and genotype × environment interaction (GEI). This study employed a Bayesian probabilistic method to study GEI by integrating adaptation and grain yield stability assessments of 22 maize hybrids within a unified framework. Using grain yield data from 22 maize hybrids tested across five research field stations (Karaj, Shiraz, Kermanshah, Kerman and Mashhad) in two years, genotypes were ranked by success probability under a 20% selection intensity. H15, H10, and H17 hybrids showed the highest marginal probability of superior performance. H15 outperformed all tested hybrids, while H10 exceeded most (p >0.90) except H15. For grain yield stability, H20, H16, and H05 hybrids ranked highest. Combining performance and grain yield stability probabilities, H20, H16, and H15 hybrids were top candidates. The Bayesian approach effectively identified genotypes with high grain yielding and yield stability, providing a robust tool for maize breeding programs. By quantifying probabilistic outcomes, this method enhances decision-making, ensuring precise selection and recommendation of maize hybrids tailored for target environments. Keywords: Maize, multi-environment trial, probability, genotype × environment interaction, grain yield stability. Introduction Genotype × environment interaction (GEI) explains how genotypes perform across different environments, which can be either simple (no change in genotype rankings) or complicated (rankings change inversely). Complicated GEI challenges plant breeders, as it indicates instability in performance of genotype, making cultivar recommendations difficult. To address this challenge, yield stability and adaptability analyses are conducted to identify adapted genotypes with high yield and yield stability across environments. Various methods have been proposed, differing in their statistical approaches and adaptability concepts. A novel approach introduced by Dias et al. (2022) introduces a Bayesian probabilistic method, which integrates prior information and ranks genotypes by superiority using selection intensity. This method addresses critical issues, such as the probability of a new genotype outperforming existing ones and the risk of failure in specific environments. By combining information from multi-environment trails, the Bayesian approach provides greater inferential power, enabling more accurate predictions and decision-making in plant breeding programs. This advancement helps breeders to identify adapted genotypes with high yield and yield stability reducing the risks associated with GEI and improving cultivar development. This study aimed to employ Bayesian probabilistic approach for risk assessment in selection and recommendation of new maize (Zea mays L.) hybrids for target environments. Materials and Methods In this study 20 promising maize hybrids and two commercial hybrids (H21 and H22) were evaluated in five research filed stations (Karaj, Shiraz, Kermanshah, Kerman and Mashhad) over two years (2023 and 2024). The experimental design was randomized complete block design with four replications. Each plot consisted four rows of 6.12 meters length with 75 centimeter row spacing, and plant density of 78,000 ha-1. Three seeds were planted in each hill, thinned to two plants at the 4-5 leaf stage. Crop management practices including; irrigation, weed control, and fertilization applications, were followed as recommended for each location. Initial statistical analysis involved simple analysis of variance for each environment to assess genotypic variation, experimental precision, and residual variance homogeneity. Then, combined analysis of variance was performed, which revealed significant genotype × environment interaction (GEI). Adaptability and grain yield stability were estimated using the method introduced by Dias et al. (2022) implemented through the ProbBreed package in R. Results and Discussion Combined analysis of variance revealed that the effects of hybrids, environments, and genotype × environment interaction (GEI) were significant (p < 0.01). This highlights the complication of GEI, and indicated that top-performing hybrids in one environment may not be excel in others, necessitating environment-specific cultivar recommendations over general adaptability. Bayesian probabilistic models were justified for more reliable recommendations. Hybrid H15 as the most promising, had the highest marginal probability of superior performance. This hybrid outperformed other hybrids, including checks, in seven out of nine environments. Hybrids H10 and H17 also ranked high with 98% and 94% probabilities, respectively, of belonging to the top-performing subset. While hybrid H15 had 71% probability of outperforming over Hybrid H10, as it underperformed in environments E03 and E07, where hybrid H10 and H17 were selected and recommended. At the 20% selection intensity, hybrid H15 was the only hybrid common to both the top-performing (H15, H10, H17, H20, H16) and high grain yield stability (H07, H03, H13, H12, H15) groups. High-performing with high grain yield stability hybrids like H15, H10, and H17 reduce risks of new hybrids selection and recommendation for target environments. These findings are in accordance with results reported by Malikouski et al. (2024) and Miranda et al. (2024), validating the reliability of Bayesian approaches in crop breeding strategies. Using the multi-traits stability index (MTSI), hybrids H15, H11, and H10 were the top-ranked hybrids. In conclusion, hybrids H15 and H10 combining superior performance, grain yield stability, and adaptability, were identified as the most promising hybrids for recommendation to target environments. Bayesian probabilistic approaches provided precise, reliable tool for hybrids recommendations by directly interpreting genotype performance and grain yield stability across test environments, enhancing decision-making in maize breeding programsu. References Dias, K.O.G., Santos, J.P.R., Krause, M.D., Piepho, H.-P., Guimarães, L.J.M., Pastina, M.M. and Garcia, A.A.F. 2022. Leveraging probability concepts for cultivar recommendation in multi-environment trials. Theoretical and Applied Genetics, 135(4), pp.1385–1399. DOI: 10.1007/s00122-022-04041-y Malikouski, R.G., Ferreira, F.M., Chaves, S.F.S., Couto, E.G.O., Dias, K.O.G., and Bhering, L.L. 2024. Recommendation of Tahiti acid lime cultivars through Bayesian probability models. PLOS ONE, 19(3), e0299290. DOI: 10.1371/journal.pone.0299290 Miranda, I.R., Dias, K.O.G., Júnior, J.D.P., Carneiro, P.C.S., Carneiro, J.E.S., Carneiro, V.Q., Souza, E.A., Melo, L.C., Pereira, H.S., Vieira, R.F. and Martins, F.A.D. 2024. Use of Bayesian probabilistic model approach in common bean varietal recommendation. Crop Science, 64(6), pp.3163-3173. DOI: 10.1002/csc2.21340 عملکرد دانه یک رقم ذرت تابع اثر ژنوتیپ، محیط و برهمکنش ژنوتیپ × محیط است. در این پژوهش، برای بررسی برهمکنش ژنوتیپ × محیط، از روشی استفاده شد که در آن روش های احتمالات بیزی و روش‌های تحلیل سازگاری و پایداری عملکرد در یک چارچوب واحد تلفیق شده است. برای این منظور، داده های 20 هیبرید امیدبخش ذرت به همراه دو شاهد تجاری (هیبریدهای H21 و H22) که در قالب طرح بلوک‌های کامل تصادفی با چهار تکرار در پنج ایستگاه تحقیقاتی (کرج، شیراز، کرمانشاه، کرمان و مشهد) در سال‌های 1402 و 1403 ارزیابی شدند، استفاده شد. در شدت انتخاب تعریف‌شده 20 درصد، هیبرید‌های H15،H10 و H17 بالاترین احتمال حاشیه‌ای عملکرد دانه برتر را داشتند، به طوریکه H15 دارای احتمال بالایی برای برتری نسبت به هر هیبریدی، از جمله ارقام شاهد بود که نشان‌دهنده مناسب بودن آن برای توصیه در مناطق ارزیابی‌شده بود. همچنین هیبرید H10 با دومین رتبه برای عملکرد دانه، دارای احتمالی بیشتر از 0/90برای برتری نسبت به اغلب هیبرید‌ها به جز H15بود. از طرف دیگر، هیبرید‌های H20، H16 و H05 به ترتیب بیشترین احتمال حاشیه‌ای پایداری عملکرد دانه برتر را داشتند. با توجه به احتمال توام عملکرد دانه برتر و پایداری عملکرد، هیبرید‌های H20، H16 و H15 برتری خود را نشان دادند. بنابراین، می توان نتیجه گیری کرد که رویکرد احتمالاتی از پتانسیل خوبی برای انتخاب و توصیه ارقام جدید ذرت برخوردار است.

https://spj.areeo.ac.ir/article_133365_e32252c6e55e55ff2d9903c8967c86e7.pdf

موسسه تحقیقات اصلاح و تهیه نهال و بذر نهال و بذر 1562-5494 40 3 2024 11 05 Development of Irrigated Durum and Bread Wheat Pure Lines in Iran using Speed Breeding: Single Seed Descent Method تولید لاین های خالص گندم دوروم و نان آبی با استفاده از بهنژادی سریع: روش انتخاب تک بذر 339 321 134076 10.22092/spj.2025.369394.1417 FA توحید نجفی میرک استاد، موسسه تحقیقات اصلاح و تهیه نهال و بذر، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران. امیر کبیری کارشناس، موسسه تحقیقات اصلاح و تهیه نهال و بذر، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران. Journal Article 2024 09 14 This research was carried out to introduce single seed descent as an applied wheat breeding for accelerating the development of pure lines. Twenty five crosses between durum wheat cultivars and landraces and four crosses between bread wheat cultivars were performed and F1 and F2 generations were produced under field conditions in 2021-2022 and 2022-2023 cropping cycles. Ninety populations of durum wheat and four population of bread wheat, in total 23 populations, were used for producing seed of F2 segregating populations, which led to pure lines using the single seed descent (SSD) method in controlled conditions in greenhouse. Each generation cycle was approximately 70–80 days. To maintain and transfer genetic variation between and within generations, a single seed was harvested from each spike in the F₂, F₃, and F₄ generations and replanted to produce the subsequent generation. In the F₅ generation, all seeds from each spike were harvested separately, and stored in individual envelopes and considered as F₆ pure lines. At the conclusion of the three-year study, a total of 1,456 F6 pure lines were developed from the 23 successful wheat crossing programs. Keywords: Wheat, hybridization, segregating generations, desirable traits, seed number. Introduction Recently, speed breeding has emerged as a novel strategy to shorten the time required to achieve pure lines and develop new crop varieties. In this method, plants are grown in controlled growth chambers or greenhouses under optimized light intensity, quality, photoperiod, and temperature, accelerating physiological processes such as photosynthesis and flowering, thereby reducing the seed-to-seed cycle. Researchers have introduced speed breeding as a powerful method to accelerate cultivar development in crop plant breeding programs (Watson et al., 2018; Hickey et al. 2019; Jin-Kyung et al., 2023). Among speed breeding techniques, the single seed descent (SSD) method has proven highly effective. In SSD method, a single seed is harvested from each self-pollinated plant per generation. This approach not only reduces generational turnover time but also minimizes inter-plant competition and natural selection pressures, thereby preserving maximal genetic diversity until homozygous purity is achieved (Watson et al., 2018). The present research was designed and implemented in greenhouse conditions with the aim of reducing the time required to develop and release of durum and bread wheat cultivars resulting from different crosses using the single seed descent breeding method. Materials and Methods In this research, 25 crosses were made between durum wheat and four crosses between bread wheat cultivars. The F₁ and F₂ generations were produced under field conditions in 2021-2022 and 2022-2023 crop seasons, respectively. From the F₂ populations, 19 durum wheat and four bread wheat populations, totally 23 segregating populations, were kept, which led to pure lines using the single seed descent (SSD) method in controlled conditions in greenhouse. Greenhouse conditions were maintained with 22 hours of light (16,000 lux) and two hours of dark periods per day. The temperature ranged from 22–25°C during the light period and 17–18°C during the dark period. Relative humidity was maintained 60–70% in all growth stages. Results and Discussion In this research, 1456 pure lines were successfully developed from 23 crosses of durum and bread wheat using single seed descent (SSD) in Karaj, Iran. The process involved: 1) Crossing and F₁ seed production (Year 1), 2) Field cultivation of F₁ to generate 19 segregating F₂ populations (Years 2), 3) Handling the F3, F4, and F5 generations in the greenhouse under optimized conditions (22-hour light/2-hour dark, 23–25°C day/17–18°C night, 70% RH) to produce pure lines (Year 3). While these steps need six years in the conventional wheat breeding methods. In other words, three years were saved to produce pure lines in SSD method. No plants were removed in this method, therefore, the maximum genetic was maintained and transferred to subsequent generations. In addition, significant savings were made in irrigation water consumption, which is commonly used for managing the segregating generations in the field as well as in human resources costs in conventional wheat breeding. Different light sources including SMD lamps with purple and yellow light with intensity of 10-13 thousand lux, LED strip lights with white, blue and purple light with intensity of 6-4 thousand lux, and conventional LED lamps with intensity of 13-16 thousand lux had no significant effect on the grain physiological maturity. However, our observation showed that the white light with an intensity of 16,000 lux led to larger wheat spikes, higher thousand-grain weight, and more grains. Also, these lamps were easier to obtain and install, and their costs was much lower than other lamps. The pure lines produced in this research will be advanced the national wheat breeding programs for target environments in southern warm and dry and temperate agro-climatic zones. It is expected that commercial cultivars will released within the next few years. References Hickey, L.T., Hafeez, A.N., Robinson, H, Jackson, S.A., Leal- Bertioli S.C.M., Tester, M., Gao, C., Godwin, I.D., Hayes, B.J. and Wulff, B.B.H. 2019. Breeding crops to feed 10 billion. Nature Biotechnology, 37, pp.744–754. DOI: 038/s41587-019-0152-9 Jin-Kyung, C., Hyeonjin, P., Changhyun, C., Youngho, K., So-Myeong, L., Ki-Won, O., Jong-Min, K., Soon-Wook, K. and Jong-Hee, L. 2023. Acceleration of wheat breeding: enhancing efficiency and practical application of the speed breeding system. Plant Methods, 19(18), pp.1-9. DOI: 10.1186/s13007-023-01083-1 Watson, A., Ghosh, S., Williams, M.J., Cuddy, W. S., Simmonds, J., Rey, M.D., Md Hatta, M.A., Hinchliffe, A., Steed, A., Reynolds, D., Adamski, N.M., Breakspear, A., Korolev, A., Rayner, T., Dixon, L.E., Riaz, A., Martin, W., Ryan, M., Edwards , D., Batley, J., Raman, H., Carter, J., Rogers, C., Domoney, C., Moore, G., Harwood, W., Nicholson, P., Dieters, M. J., Lacy, I.H., Zhou, J., Uauy, C., Boden, S.A., Park, R.F., Wulff, B.H. and Hickey L.T. 2018. Speed breeding is a powerful tool to accelerate crop research and breeding. Nature Plants, 4, pp.23-29. DOI: 10.1038/s41477-017-0083-8 Yao, Y., Zhang, P., Liu, H., Lu, Z., and Yan, G. 2016. A fully in vitro protocol towards large scale production of recombinant inbred lines in wheat (Triticum aestivum L.). Plant Cell, Tissue and Organ Culture, 128, pp.655– 661. DOI: 10.1007/s11240-016-1145-8 این پژوهش با هدف تولید لاین های جدید گندم دوروم و نان آبی با استفاده از بهنژادی سریع، روش انتخاب تک بذر (SSD)، در بخش تحقیقات غلات موسسه تحقیقات اصلاح و تهیه نهال و بذر در سال های زراعی 1400-03انجام شد. براساس اهداف برنامه بهنژادی گندم نان و دوروم، تعداد 25 برنامه دورگ گیری بین ارقام گندم دوروم و چهار برنامه دورگگیری بین ارقام گندم نان در سال زراعی 01-1400 انجام و در سال بعد در شرایط مزرعه نسل های F1 و F2 ارزیابی و تولید شد. پس از حذف نتاج شش دورگگیری گندم دوروم، بذور تعداد 23 جمعیت F2 در شرایط کنترل شده گلخانه و با استفاده از روش انتخاب تک بذر (SSD) برای تولید لاین های خالص کشت شدند. شرایط گلخانه شامل 22 ساعت روشنایی و دو ساعت تاریکی به ترتیب با دمای دما در دوره تاریکی 18-17 درجه سانتی گراد و در دوره روشنایی 25-23 درجه سانتی گراد و رطویت 70-60 درصد بود. مدت زمان تولید بذر در هر نسل حدود 80-70 روز طول کشید. در نسلهای F2، F3 و F4 از هر سنبله یک بذر برداشت و برای تولید نسل بعد کشت شد. در نسل F5 کلیه بذور هر سنبله بطور جداگانه در یک پاکت برداشت و به عنوان لاین های خالص نسل F6 وارد مراحل بعدی برنامه بهنژادی گندم آبی کشور گردید. در پایان دوره این پژوهش، از 23 دورگ گیری، 1456 لاین نسل F6 تولید و در سال زراعی بعد در شرایط مزرعه برای ازدیاد بذر و انتخاب لاین های خالص دارای صفات مطلوب زراعی کشت می شوند. اگر این فرایند به روش های بهنژادی متداول انجام می شد، هفت سال طول می کشید، بنابراین، با این روش چهار سال در زمان مورد نیاز برای تهیه لاین خالص جدید صرفه جویی می شود. هزینه های تولید لاین های خالص گندم نیز به طور قابل توجهی کاهش می یابد.

https://spj.areeo.ac.ir/article_134076_a431243ed72644d86079524e4d762091.pdf

موسسه تحقیقات اصلاح و تهیه نهال و بذر نهال و بذر 1562-5494 40 3 2024 11 08 Effect of Two Semi-dwarf OH×F87TM and Pyrodwarf Rootstocks on Iron Absorption and Chlorophyll Related Characteristics of Leaves in Some Commercial Pear Cultivars اثر دو پایه نیمه‌پاکوتاه OH×F87TMو پیرودوارف بر جذب آهن و خصوصیات مرتبط با سبزینگی برگ برخی ارقام تجاری گلابی 361 341 134163 10.22092/spj.2025.368157.1398 FA مینا بیاناتی پژوهشگر، پژوهشکده میوه‌های معتدله و سردسیری، موسسه تحقیقات علوم باغبانی، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران. حمید عبدالهی دانشیار، پژوهشکده میوه‌های معتدله و سردسیری، موسسه تحقیقات علوم باغبانی، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران. مهیار طاووسی نائینی کارشناس تحقیقاتی، پژوهشکده میوه‌های معتدله و سردسیری، موسسه تحقیقات علوم باغبانی، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران. Journal Article 2024 09 04 Iron absorption, leaf chlorophyll content and tolerance to leaf chlorosis are among important chrachteristics in the final selection of pear rootstocks for cultivation in alkaline and semi-alkaline soils of Iran. Therefore, this study aimed to evaluate the total iron absorption potential, active iron content, and their impacts on leaf chlorophyll content in four commercial pear cultivars grafted on two OH×F87TM and Pyrodwarf rootstocks. Pear cultivars; cv. Packham's Triumph, cv. Spadona, cv. Dergazi, and cv. Louis Bonne were grafted on OH×F87TM and Pyrodwarf rootstocks. The experiment was carried-out as factorial arrangements in randomized complete block design wsith three replications and three experimental factors; rootstock at two levels, pear cultivars at four levels and leaf position at two levels. Results indicated significant effect of rootstock, cultivar, and leaf position on total iron, active iron, chlorophyll a, and b, total chlorophyll, and leaf colorimetric indices. Active iron in the leaves of pear cultivars varied from 19.76% to 20.7% of total iron. The higher active iron content in the OH×F87TM rootstock (86.32 mg kg-1 dw) suggests its adaptability to moderate level of active lime in the soil. Among the pear cultivars, cv. Dergazi had the highest total chlorophyll content, while cv. Spadona had the lowest. The rootstock × cultivar × leaf position effect on colorimetric indices, L*, a*, b*, and cv. Dergazi cultivar on OH×F87 TM rootstock showing the lowest a* and b* indices and the highest iron and total chlorophyll content. Keywords: Pear, total iron, active iron, colorimetric index, chlorophyll content, SPAD index. Introduction Pear (Pyrus communis L.) is among the five most important fruits in the world mainly due to its high adaptability to different climatic conditions. Iran is one of the main centers of diversity of the genus Pyrus in the world, and different cultivars of common pear belonging to the species P. communis L. are well adapted to the temperate climate of this region (Abdollahi, 2010). Accordingly, the cultivation of pear trees in Iran has a history of several thousand years, and traditional orchards of this fruit tree have developed and improved over the past few decades (Abdollahi, 2010; Abdollahi, 2021). Currently, one of the main components in the development and improvement of pear orchards is usage of semi-dwarf and dwarf rootstocks with adaptability to the climatic and soil conditions of the pear production areas in Iran. Adaptability tests of different pear cultivars and rootstocks demonstrated the impact of both on fruit yield, fruit quality and the final size of pear trees in commercial orchards (Alizadeh Fallahet al., 2022). During recent decades, Pyrodwarf rootstock has been identified as a suitable rootstock for promoting early fruiting potential and reducing tree size in pear orchards established by commercial cultivars such as Dergazi, Louise Bonne and Spadona (Abdollahi, 2021). Additionally, OH×F rootstock series, paricularly OH×F217 and OH×F87, have shown promising results for fruit yield and quality. These impacts of rootstocks express in various ways, including crown volume, vigor, and growth habit induced in the grafted cultivars. The rootstocks also affect tolerance to the alkaline soils, which in turn affects the rate of iron absorption and transfer to cultivars and ultimately leaf chlorophyll content (Fallahi et al., 2002). Tthis study aimed to compare Pyrodwarf and OH×F87TM rootstocks effect on iron absorption and leaf chlorophyll content in different grafted pear cultivars. Materials and Methods The trees were grafted on two rootstocks, Pyrodwarf and OH×F87TM, with four fire blight tolerant commercial pear cultivars including; cv. Packham's Triumph, cv. Spadona, cv. Dargazi, and cv. Louise Bonne. The trees were seven years old at the time of evaluation. The experiment was factorial arrangements in randomized complete block design with three replications and tthere experimental factors; rootstaock at two levels, cultivar at four levels and leaf position at two levels. Each experimental plot consisted of six trees of each scion/rootstock combination. Sampling was conducted in August 2024 to assess the iron absorption characteristics; total iron and active iron, as well as leaf chlorophyll content and leaf colorimetric indices. Leaf samples were collected from the lower and upper leaves of the shoots from the current season growth. These samples were then taken to the laboratory, where the leaf chlorophyll content was determined based on the SPAD index (SPAD, DCH-52p Minolta, Japan). Total iron conten was measured colorimetrically using orthophenanthroline reagent and read at 515 nm in a spectrophotometer. The chlorophyll a and b contents, and total chlorophyll content were measured using the spectrophotometric method with 80% acetone solvent and at 663 and 645 nm wavelengths. Analysis of variance for data was performed using SAS 9.2 software. The least significant difference (LSD) test was employed for means comparison at the 5% probability level. Results and Discussion Data analysis revealed that the effects of rootstock, cultivar, and leaf position were significant on the total iron, active iron, chlorophyll a, chlorophyll b, total chlorophyll contents, and leaf colorimetric indices. Additionally, rootstock × cultivar × leaf position on these traits were significant, except for chlorophyll b. The lack of significant differences in total iron content between the two rootstocks, OH×F87TM and Pyrodwarf, suggests that rootstock OH×F87TM is suitable for soils with moderate levels of active lime. This is supported by the slightly higher active iron content in rootstock OH×F87TM compared to Pyrodwarf. Comparison of colorimetric indices revealed significant difference between two rootstocks, OH×F87TM and Pyrodwarf, in a*, b*, R, G, and B indices, with the exception of the L* index. In conclusion, the comparison between two rootstocks showed that OH×F87TM rootstock can be considered and recommended as a suitable rootstock, and even superior to Pyrodwarf, for establishing semi-dwarf pear orchards in regions with soils of moderate levels of active lime. References Abdollahi, H. 2010. Pear: botany, cultivars and rootstocks. Ministry of Agriculture, Tehran, Iran. 210 pp. (in Persian). Abdollahi, H. 2021. Comparison of bearing and yield efficiency of commercial pear cultivars on pyrodwarf semi-dwarfing rootstock. Seed and Plant Journal, 37(4), pp.399-423 (in Persian). DOI: 10.22092/sppi.2022.356262.1254 Alizadeh Fallah, M., Yadegari, M., Davarynejad, Gh. and Nemati, S.H. 2022. The rootstock and scion interaction effects on growth and bearing characteristics of young pear trees. Journal of Horticultural Science, 36(2), pp.519-531. (in Persian). DOI: 10.22067/JHS.2022.73938.1112 Fallahi, E., Colt, W.M., Fallahi, B. and Chun, I.J. 2002. The importance of apple rootstocks on tree growth, yield, fruit quality, leaf nutrition, and photosynthesis with emphasis on Fuji. Horticultural Technology, 12(1), pp.38-44. DOI:10.21273/HORTTECH.12.1.38 از مهمترین شاخصها در گزینش نهائی پایههای گلابی برای کشت در مناطق پرورش این محصول در کشور، خصوصیات مرتبط با جذب آهن و سبزینگی برگ و عدم بروز کلروز برگی در ارقام پیوند شده میباشد. بر این اساس، پژوهش حاضر با هدف ارزیابی قدرت جذب آهن کل و میزان آهن فعال و اثرآن بر روی خصوصیات مرتبط با سبزینگی برگ در چهار رقم تجاری گلابی روی دو پایه پیرودوارف و OH×F87TM در سال 1403 در ایستگاه تحقیقات باغبانی کمالشهر کرج اجرا شد. ارقام گلابی مورد بررسی شامل چهار رقم، پکهامزتریومف، اسپادونا، درگزی و لوئیزبون بودند. طرح آزمایشی به صورت فاکتوریل در قالب طرح بلوکهای کامل تصادفی با سه تکرار با سه عامل پایه در دو سطح، رقم در چهار سطح و موقعیت برگ در دوسطح بود. نتایج بیانگر معنیدار بودن اثر پایه، رقم و موقعیت برگ روی صفات آهن کل، آهن فعال، کلروفیل کل،کلروفیلa و b و همچنین شاخصهای رنگسنجی برگ بود. عدم وجود تفاوت معنیدار بین دو پایه مورد بررسی در رابطه با میزان آهن کل و از طرف دیگر، وجود میزان بالاتری از محتوای آهن فعال، به میزان 86/2میلیگرم بر کیلوگرم وزن خشک برگ، درارقام پیوندی روی پایه OH×F87TM نشاندهنده مطلوبیت نسبی این پایه در خاکهایی با سطح متوسطی از آهک فعال بود. دامنه درصد آهن فعال برگ نسبت به آهن کل، در ارقام گلابی مورد بررسی از 19/76درصد تا 20/7درصد متفاوت بود. همچنین بیشترین محتوای کلروفیل کل در برگهای رقم درگزی و کمترین مقدار کلروفیل کل در رقم اسپادونا در مقایسه با سایرارقام مشاهده شد. پایه، رقم و موقعیت برگ بر شاخصهای رنگ سنجی b*، a* وL* برگ اثرگذار بودند. حداقل شاخص a* و b* در ترکیب پیوندی رقم درگزی روی پایه OH×F87TM مشاهده شد، درحالیکه این ترکیب پیوندی از نظر محتوای آهن و کلروفیل کل، بیشترین میزان را دارا بود. نتایج این پژوهش نشان داد که پایه OH×F87TM 7از توانایی مطلوبی در مقایسه با تجاری پیرودوارف در رابطه با جذب و نگهداری آهن به فرم آهن فعال برخوردار بود.

https://spj.areeo.ac.ir/article_134163_34eac3a66b829305941868a6f53cce75.pdf

موسسه تحقیقات اصلاح و تهیه نهال و بذر نهال و بذر 1562-5494 40 3 2024 11 10 Effect of Soil Application of Magnesium Sulfate on Fruit Quantitative and Quality Characteristics of Date Palm (Phoenix dactylifera L.) cv. Mazafati اثر کاربرد خاکی سولفات منیزیم بر خصوصیات کمی و کیفیت میوه نخل خرما (.Phoenix dactylifera L) رقم مضافتی 386 363 134203 10.22092/spj.2025.369835.1427 FA بهاره دامن کشان مربی، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی استان کرمان، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرمان، ایران. ایران بهمن پناهی دانشیار، پژوهشکده پسته، موسسه تحقیقات علوم باغبانی، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرمان، ایران. جواد فرخی استادیار، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی استان کرمان، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرمان، ایران. Journal Article 2024 08 04 To investigate the effects of different magnesium sulfate on fruit quantitative and quality characteristics of date palm (Phoenix dactylifera L.) cv. Mazafati, a field experiment was carried out using randomized complete block design with three replications in palm date orchard cv. Mazafati in Baravat district of Bam, Kerman province, in Iran, in two growing seasons (2022 and 2023). The experimental treatments were four levels (0, 250, 500, and 750 g tree-1) of soil applied magnesium sulfate. The results showed that magnesium sulfate levels had significant effect on fruit yield, fruit diameter, seed length, total soluble solids (TSS), and leaf magnesium content. The 250 g level had the highest fruit yield and quality, while the 750 g level showed the highest leaf magnesium content. In conclusion, soil application of magnesium sulfate improved fruit yield, fruit quality and pomological traits. The results underlined the importance of megensium role in improvement of productivity and fruit quality of date palm trees cv. Mazafati. Keywords: Date palm, orchard, fruit diameter, pomological traits, fruit yield. Introduction In recent years, numerous studies have investigated the role of magnesium in improving plant growth, yield, and fruit quality. Tränkner et al. (2019) highlighted the importance of magnesium in biomass production and chlorophyll synthesis. Similarly, research by Assis (2024) emphasized the role of magnesium in enhancing plant tolerance to abiotic stresses. In most of these studies, the effects of soil-applied magnesium were examined (Zhang et al., 2021). Unlike previous research, which mainly focused on other fruit crops, this study specifically assesses the effects of different levels of soil applied magnesium sulfate on the fruit quantitative and quality characteristics of date palm cv. Mazafati under the climatic conditions of Kerman province. This study aimed to determine the optimum level of soil application of magnesium sulfate levels to improve fruit yield and quality traits of date palms cv. Mazafati in arid and semi-arid regions in Iran. Materials and Methods This research was carried out in two phases. First, the nutritional status of 15 cv. Mazafati date palm orchards in Kerman Province (Baravat, Bam, Shahdad, Fahraj, Rigan, Narmashir, Anduhjerd, and Chahar-Farsakh) was assessed. Leaf samples were analyzed for nitrogen, phosphorus, potassium, calcium, and magnesium. Data were processed in mean comparisons. Second, the main field experiment was carried out in two growing seasons (2022 and 2023) in Baravat district, Bam, Kerman Province, in Iran, on 20-year-old date palm trees cv. Mazafati using randomized complete block design with three replications and four soil applied magnesium sulfate levles 0 (control), 250, 500, and 750 g MgSO₄ tree-1. Routine orchard management practices were uniformly applied. At harvest, fruit yield tree-1, fruit weight, fruit diameter, seed length, fruit flesh: seed ratio, and total soluble solids (TSS) were measured. Leaf Mg content was determined by complexometric titration. Combined analysis of variance and mean comparision LSD tests at the 5% probability level was perfermed using SPSS (Version 26) software. Results and Discussion The results showed that despite non-significant differences in nitrogen and phosphorus contents between the control and experimental date palm orchards, potassium and calcium levels were higher, while magnesium levels were lower in the experimental orchards compared to the control. In 85% of the leaf samples, leaf magnesium contents were lower than normal thresholds, which could potentially reduce fruit yield and quality. The higher potassium contents likely inhibited magnesium uptake in the experimental orchard (Zhang et al., 2021). Soil application of 250 g magnesium sulfate tree-1 resulted in the highest fruit yield (74.66 kg tree-1) and fruit diameter (2.31 cm). This treatment also had the highest TSS content (66.33%). However, excessive magnesium sulfate application (500 and 750 g tree-1) led to reduction in TSS, likely due to disturbances in cation balance and the uptake of other nutrient elements. Our findings are in consistent with the findings of Wang et al. (2021). Therefore, balanced soil applied magnesium sulfate was effective in correcting nutrient deficiencies and improving fruit yield and quality characteristics of date palm cv. Mazafati. References Assis, V.C.S.S. 2024. Magnesium dynamics in the soil-plant system and its role in plant metabolism and nutrition: a review. Scientific Electronic Archives, 17(4), pp.1-10. DOI: 10.36560/17420241898 Tränkner, M. and Jaghdani, S.J. 2019. Minimum magnesium concentrations for photosynthetic efficiency in wheat and sunflower seedlings. Plant Physiology and Biochemistry, 144, pp.234-243. DOI: 10.1016/j.plaphy.2019.09.040 Wang, Z., Hassan, M.U., Nadeem, F., Wu, L., Zhang, F. and Li, X. 2020. Magnesium fertilization improves crop yield in most production systems: a meta-analysis. Frontiers in Plant Science, 10, 495191. DOI: 10.3389/fpls.2019.01727 Zhang, S.W., Yang, W.H., Muneer, M.A., Ji, Z.J., Tong, L. and Zhang, X. 2021. Integrated use of lime with Mg fertilizer significantly improves the pomelo yield, quality, economic returns and soil physicochemical properties under acidic soil of southern China. Scientia Horticulturae, 290, 110502. DOI: 10.1016/j.scienta.2021.110502 منیزیم از جمله عناصر غذایی مؤثر بر عملکرد، کیفیت و طعم میوه خرما است. در این پژوهش، اثر کاربرد خاکی سولفات‌منیزیم (MgSO4.7H2O) بر خصوصیات کمی و کیفیت میوه نخل خرما رقم مضافتی در قالب طرح بلوک‌های کامل تصادفی با سه تکرار و چهار تیمار (0، 250، 500 و 750 گرم سولفات‌منیزیم به‌صورت کاربرد خاکی در هر درخت)، بر روی 12 نفر نخل خرمای 20 ساله رقم مضافتی در دو سال زراعی (1401 و1402) در نخلستانی در بروات از توابع شهرستان بم در استان کرمان بررسی شد. نتایج نشان داد اثر سطوح تیمار سولفات‌منیزیم بر عملکرد میوه درخت، قطر میوه، میزان مواد جامد محلول کل ((TSS خرما و غلظت منیزیم در برگ در سطح احتمال یک درصد و بر طول هسته خرما در سطح احتمال پنج درصد معنی‌دار بود. بیشترین عملکرد میوه درخت (74/66کیلوگرم در درخت)، بیشترین قطر میوه (2/31سانتی‌متر) و بالاترین مقدار TSS میوه (33/66 درصد) مربوط به تیمار سولفات منزیم به میزان 250 گرم در هر درخت بود. بیشترین میزان منیزیم در برگ (0/1883درصد) و کمترین طول هسته (1/98سانتی‌متر) در تیمار 750 گرم سولفات منیزیم ثبت شد. این یافته‌ها نقش حیاتی سولفات‌منیزیم را در بهینه‌سازی بهره‌وری عملکرد و کیفیت میوه نخل خرما رقم مضافتی برجسته کرده و بر ضرورت مدیریت مناسب و بهینه کودهای دارای عنصر منیزیم در نخلستان های منطقه تاکید می کند. بنابراین، استفاده بهینه از سولفات‌منیزیم می‌تواند به عنوان راهکاری عملی جهت ارتقاء کمیت و کیفیت میوه خرما رقم مضافتی مورد بهره‌برداری قرار گیرد.

https://spj.areeo.ac.ir/article_134203_7a076b2ec77473d58c8bba190fe10439.pdf

موسسه تحقیقات اصلاح و تهیه نهال و بذر نهال و بذر 1562-5494 40 3 2025 01 02 A Review of Objectives, Programs and Advances in Breeding of Apple Clonal Rootstocks in Iran مروری بر اهداف، برنامه‌ها و پیشرفت‌های اصلاح پایه‌های رویشی درخت سیب در ایران 387 423 134705 10.22092/spj.2025.370644.1440 FA داریوش آتشکار استادیار، پژوهشکده میوه های معتدله و سردسیری، موسسه تحقیقات علوم باغبانی، سازمان تحقیقات،آموزش و ترویج کشاورزی، کرج، ایران. رعنا دستجردی دانشیار، پژوهشکده میوه های معتدله و سردسیری، موسسه تحقیقات علوم باغبانی، سازمان تحقیقات،آموزش و ترویج کشاورزی، کرج، ایران. مسعود لطیفیان استاد، پژوهشکده میوه های معتدله و سردسیری، موسسه تحقیقات علوم باغبانی، سازمان تحقیقات،آموزش و ترویج کشاورزی، کرج، ایران. قاسم حسنی مربی، بخش تحقیقات علوم زراعی و باغی، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی استان آذربایجان غربی، سازمان تحقیقات،آموزش و ترویج کشاورزی، ارومیه، ایران. منصوره کشاورزی دانشیار، پژوهشکده میوه های معتدله و سردسیری، موسسه تحقیقات علوم باغبانی، سازمان تحقیقات،آموزش و ترویج کشاورزی، کرج، ایران. Journal Article 2024 10 31 Developing new horticultural crops cultivars and rootstocks is possible through various breeding methods including hybridization, identification and collection of high yield and high quality native genotypes, as well as evaluating the adaptability of commercial introduced cultivars. The utilization of new cultivars and rootstocks adapted to a region’s climatic conditions plays a significant role in enhancing both the quantitative and quality attributes of crop production. The apple rootstocks breeding program in Iran started in 2005. Within this research program, in addition to assessing the adaptabilty of commercial apple rootstocks, native rootstock genotypes such as Azayesh Isfahan, Morabaei Mashhad, Gami Almasi, and Sibgol have been identified, collected and evaluated. Important characteristics for selecting apple promising rootstocks include clonal propagation ability, proper establishment in the soil, early bearing and suitable performance of grafted trees as well as resistance/tolerance to biotic and abiotic stresses such as collar and root rot, fire blight, woolly aphid, drought stress, and high lime content in the soil. Hybridization between native genotypes and commercial rootstocks is practiced in Iran’s apple rootstock breeding program. Promising apple rootstocks developed in this program will be commercially released. Keywords: Apple, rootstock, tolerance, Phytophthora, fire blight, woolly aphid, drought stress. Introduction Iran is not only one of the major apple producing regions in the world, but also one of the natural habitats, centers of diversity and areas of initial apple distribution in the world (James and Aldwinckle, 1983). Therefore, so far, numerous species and cultivars of this crop have been identified and reported by botanists in Iran. The existence of this genetic diversity and dwarf varieties in ancient Iran was such that a number of ancient miniatures not only depicted the apple tree as one of the main varieties of gardens, but also clearly indicated the existence of dwarf apple varieties in this land. Although dwarf apple trees have been found in the northern forests and highlands of West Azerbaijan, Khorasan, and Isfahan provinces since ancient times. Botanists consider Iran to be one of the areas where ornamental apples, including Morabaei, Azayesh, Sib Gol, and Gamii Almasii, have originated. Apple trees are mainly found in the form of rootstocks and scions. Rootstocks are responsible for tree establishment and water and nutrient uptake, and also have important effects on scion growth and development, fruit yield and quality, and resistance to biotic and abiotic stresses (Wang et al., 2019). To optimally utilize valuable water and soil resources, it is essential to establish high density and semi-density orchards using suitable and adapted apple rootstocks. Each country use specific rootstocks according to its climatic conditions. Europe began the commercial use of dwarf apple rootstocks relatively early. Currently, apple-producing countries in Europe mainly use clonal rootstocks. In the Britain, France and the Netherlands, the objectives of breeding are to improve the currently used rootstocks, such as M9 and M26, with better performance in terms of production, fruit size and quality, resistance to soil-borne diseases and pests and competition with weeds for water and nutrients. When carrying out apple rootstock breeding, we must first pay attention to the horticultural characteristics (grafting compatibility, propagation ability, dwarfing, effect on scion growth, etc.). In addition, we must also consider environmental factors (temperature, irrigation, soil pH and fertility, etc.) and biological factors (viruses, bacteria, nematodes, apple woolly aphid and other destructive animals) in the planting area (Robinson et al., 2003). Important charactristics in improving apple rootstocks: 1. Selection for rooting and clonal propagation ability. The most important characteristic of rootstocks is their ability clonal propagation. If the selected genotype is resistant/tolerant to various stresses but does not have the ability for clonal propagation, it should be screened in the first stage. 2. Selection for micropropagation ability. Micropropagation of apple plays an important role in producing healthy, disease-free plants and rapid propagation of scions and rootstocks with desirable characteristics. Successful micropropagation of apple using apical bud or branch segment culture is influenced by several internal and external factors, including plant material (such as genotype and physiological state) and laboratory conditions (such as medium components and light). 3. Selection for resistance to crown and root rot disease (Phytophthora cactorum) crown and root rot disease of apple trees, especially in areas with poor soil drainage, causes the death of quite large trees. Researchers have conducted extensive research on the evaluation and selection of disease-resistant rootstocks for effective disease management in an integrated control system. According to the Cornell University Rootstock Improvement Protocol, screening the progeny population resulting from cross-breeding in apple rootstocks for Phytophthora diseases is considered one of the most important steps in rootstock development (Fazio et al., 2022). 4. Selection for tolerance to drought stress. Investigating the response of plants to drought stress using physiological indicators has been proven in many studies. The main goals of improving apple rootstocks is tolerance to drought stress. Tolerant rootstocks can transfer drought tolerance to the cultivars grafted onto them. 5. Selection for fire blight toleranceFire blight is transmitted to the tree through rootstocks, and if the rootstock is susceptible, the disease spreads rapidly in the tree and the tree dries up. Therefore, in apple rootstock breeding programs, fire blight resitance is considered one of the first and most important rootstock screenings criteria. 6. Selection for tolerance to apple woolly aphid appleThe apple woolly aphid is not usually controlled with pesticides because aphids often reside in bark crevices, which reduces their exposure to pesticides, and the protection provided by the waxy secretion on their bodies minimizes the effectiveness of chemical control. Today, many apple rootstock breeding programs emphasize resistance to apple woolly aphid and diseases in addition to desirable horticultural traits. 7. Selection for dwarfing and early fruiting. The evaluation of the dwarfing and the growth ability of the progeny are considered to be the most important indicators for the selection of promising clonal rootstocks (Johnson, 2000). The best method for evaluating the dwarfing ability of rootstocks is to graft apple varieties onto them and evaluate them in the orchard. To achieve apple rootstocks with adaptabilty to soil conditions in apple growing areas, crosses between native Iranian dwarf apple genotypes (Azayesh Isfahan and Morabaei Mashhad) as maternal parents and M9, M27, and B9 rootstocks as paternal parents have been carried out from 2005 to 2008, and a population of over 4000 seedlings resulting from the crossing and open pollination of the parents reached the evaluation stage. Primary evaluation for selection of easy rooting apple rootstocks in mound bed layering condition in two stages (from2009 to 2015) was carried out. Among 4000 hybrid and open pollinated seedlinges, 245 genotypes with high rooting ability were selected. These progenies remained for continuing screening in second phase of project included: rooting ability of hard wood cutting, in the second screening 27 genotype with high rooting ability was selected. The resultes showed that in different cross combination, progenies of Azayesh×M27, Azayesh×M9 and Azayesh open pollinated had high rooting ability, and progenies of Morabaei had low rooting. In addition to progenies of Azayesh have good characteristics as rootstock than progenies of Morabaei. Rooting type of progeny was very different, the number of deep root in open pollination progeny of native genotypes was more than commercial apple rootstocks. This characteristic is very important for drought tolerance and adaptability of rootstocks. Then the level of tolerance to biotic and abiotic stresses, including crown and root rot disease, fire blight, woolly apple aphid (Eriosoma lanigerum), drought stress tolerance, micro-propagation, and dwarfing ability of the promising genotypes were tested. It is expected that four promising apple rootstocks will be commercially released and available to apple growerds in Iran. References Fazio, G., Aldwinkel, H.S. and Robinson T.L. 2022. Selection of apple rootstock breeding families for Phytophthora crown rot resistance. Acta Horticulturae, 1346, pp.717-722. DOI: 10.17660/ActaHortic.2022.1346.90. James, N.C. and Aldwinckle, H. 1983. Breeding Rootstocks. Plant Breeding Reviews, 1, pp. 295-394. Johnson. W.C. 2000. Methods and results of screening for disease and insect apple rootstocks. The Compact Fruit Tree, 33, pp.108-111. Robinson, T.L., Fazio, G. and Aldwinckle, H.S. 2012. December. Characteristics and performance of four new apple rootstocks from the Cornell-USDA apple rootstock breeding program. Acta Horticulturae, 1058, pp.651-656. DOI: 10.17660/ActaHortic.2014.1058.85 Wang, Y., Li, W., Xu, X., Qiu, C., Wu, T., Wei, Q., Ma, F., and Han, Z. 2019. Progress of apple rootstock breeding and its use. Horticultural Plant Journal, 5(5), pp.183–191. DOI: 10.1016/j.hpj.2019.06.001 تولید ارقام و پایه های جدید محصولات باغبانی با استفاده از روشهای مختلف اصلاحی شامل شناسایی و جمع‌آوری ژنوتیپ های بومی پرمحصول و باکیفیت، دورگگیری‌های هدفمند، و همچنین بررسی سازگاری ارقام تجاری آنها امکان‌پذیر است. استفاده از ارقام و پایه های جدید سازگار با اقلیم یک منطقه، نقش مهمی را در افزایش کمّی و کیفیت محصول ایفا می کند. بر این اساس، برنامه‌ اصلاح پایه‌های رویشی سیب در ایران از سال 1384 آغاز شده است. در این برنامه، ضمن شناسایی و جمع‌آوری بررسی پایههای بومی آزایش اصفهان، مربایی مشهد، گمی‌آلماسی و سیبگل، سازگاری پایه های رویشی تجاری سیب نیز ارزیابی شدند. صفات مهم درگزینش پایه های سیب، شامل قابلیت تکثیر رویشی، استقرار مناسب در خاک، زودباردهی، عملکرد میوه مناسب درختان پیوندی، تحمل به تنشهای زنده و غیرزنده از جمله بیماری پوسیدگی طوقه و ریشه، بیماری آتشک، تحمل به آفت شته مومی، تحمل به تنش خشکی و میزان آهک فعال بالا در خاک بوده است. همچنین انجام دورگ‌گیریهای هدفمند بین پایه های رویشی بومی و پایه های رویشی تجاری، از دیگر فعالیت‌های انجام‌شده در برنامه اصلاح پایه‌های سیب در ایران بوده است. نتاج حاصل از دورگ‌گیری ها وگرده‌افشانی آزاد والدین، به لحاظ صفات مهم در گزینش پایه های رویشی، غربال شده و پایه های امیدبخش سیب در دست معرفی می‌باشند.

https://spj.areeo.ac.ir/article_134705_616aaa42397e6f523b4a31f40bfea9cb.pdf

موسسه تحقیقات اصلاح و تهیه نهال و بذر نهال و بذر 1562-5494 40 3 2025 02 08 Reaction of Some Irrigated Bread Wheat Gdnotypes of the National Breeding Programs for Temperate and Northern Warm and Humid Agro-climatic Zones to Yellow and Stem Rusts at the Seedling and Adult Plant Stages واکنش برخی از ژنوتیپ های گندم نان آبی برنامه های ملی به نژادی اقلیم های معتدل و گرم و مرطوب شمال نسبت به زنگ‌های زرد و ساقه در مرحله گیاهچه‌ای و گیاه بالغ 456 425 134886 10.22092/spj.2025.370622.1439 FA صفرعلی صفوی دانشیار، بخش تحقیقات علوم زراعی و باغی، مرکز تحقیقات و آموزش کشاورزی و منابع طبیعی استان اردبیل، سازمان تحقیقات، آموزش و ترویج کشاورزی، اردبیل، ایران. فرزاد افشاری استاد، بخش تحقیقات غلات، موسسه تحقیقات اصلاح و تهیه نهال و بذر، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران. علی ملیحی پور دانشیار، بخش تحقیقات غلات، موسسه تحقیقات اصلاح و تهیه نهال و بذر، سازمان تحقیقات، آموزش و ترویج کشاورزی، کرج، ایران. Journal Article 2024 11 30 Lack of durable resistance in wheat cultivars is a major cause of yellow rust (Puccinia striiformis f. sp. tritici, Pst) and stem rust (Puccinia graminis f. sp. tritici, Pgt) epidemics, which severely affecting global wheat production. This study identified resistance sources at the seedling and adult plant stages among 44 wheat genotypes adapted to temperate and northern warm and humid agro-climatic zones of Iran. Seedling evaluation carried-out at glassohuses at Cereal Research Department, Seed and Plant Improvement Institutie in Kataj, Iran. Field evaluations were conducted in 2018–19 and 2019–20 at the Ardabil Agricultural Research Station. Adult plant resistance was assessed using epidemiological parameters: coefficient of infection (CI), final rust severity (FRS), and relative area under the disease progress curve (rAUDPC). Seedling reactions were evaluated under controlled conditions against two Pst and four Pgt pathotypes. For yellow rust, 12 (27.2%), 20 (45.4%), and 12 (27.2%) genotypes exhibited slow-rusting resistance (SR), all-stage resistance (ASR), and adult plant resistance (APR), respectively. For stem rust, 12 (27.2%) showed SR, 2 (4.5%) had ASR, and 30 (68.2%) were susceptible. Genotypes susceptible at the seedling stage but resistant at the adult stage likely carry multiple APR or slow-rusting genes, offering valuable genetic resources for development of bread wheat cultivars with durable resistance. Keywords: Bread wheat, race-specific resistance, non-race-specific resistance, slow rusting. Introduction Bread wheat is a staple food crop and essential for global food security, particularly in Mediterranean regions. In Iran, bread wheat production is consistently challenged by some biotic and abiotic stresses. Rust diseases are among the most devastating biotica stresses. The dynamic and rapid evolution of yellow rust (Pst) and stem rust (Pgt) populations may overcome race-specific resistance genes those are deployed in commercial cultivars. Periodic epidemics and substantial economic losses are possibly occurred subsequently (Chen, 2020). The emergence of virulent races such as the Ug99 lineage for stem rust has further highlighted the vulnerability of genetically similar commercial cultivars. In contrast, adult plant resistance (APR), often expressed as slow rusting, is typically polygenic and considered more durable (Huerta-Espino et al., 2020; Singh et al., 2011). This type of resistance slows disease development through mechanisms that are not pathogen race-specific. Therefore, the identification and employment of APR sources into breeding programs is a principal strategy to obtain sustainable bread wheat production. This study was designed to phenotypically characterize a collection of Iranian wheat genotypes for both seedling and adult plant resistance to stripe and stem rusts, with the goal of identifying potential donors of durable resistance. Materials and Methods The study consisted of controlled seedling tests and field evaluations. Forty-four wheat genotypes from the national bread wheat breeding programs for temperate and northern warm and humid agro-climatic zones were evaluated for their reaction to yellow rust and stem rust at the seedlingand adult plant resistances. For seedling resistance screening, plants were inoculated with two Pst pathotypes (174E150A+, Yr27 and 14E158A+, Yr27) and four Pgt pathotypes (TTTTF, PTRTF, TKTTF, TTKTK). Infection types (ITs) were assessed 14 days post-inoculation using a standardized 0–4 scale. Field evaluations were conducted at the Ardabil Agricultural Research Station over two cropping cycles (2018-19 and 2019-20). Stripe rust was evaluated under artificial epiphytotic conditions, while stem rust was assessed under natural infection. Resistance at the adult plant stage was quantified using three significant epidemiological parameters including final rust severity (FRS), coefficient of infection (CI = FRS × constant value of host response), and the relative area under the disease progress curve (rAUDPC). Genotypes were grouped into four resistance groups: all-stage resistance (ASR), adult plant resistance (APR), slow rusting resistance (SR), and susceptible, based on established thresholds for these parameters (Zeng et al., 2014). Correlation coefficients were calculated to understand the relationships between resistance parameters. Results and Discussion Seedling screening tests revealed that none of the bread wheat genotypes exhibited resistance to all pathotypes of both rust diseases under controlled conditions. However, significant levels of adult plant resistance were observed in field evaluations. For yellow rust, 12 (27.2%), 20 (45.4%), and 12 (27.2%) genotypes exhibited slow-rusting resistance (SR), all-stage resistance (ASR), and adult plant resistance (APR), respectively. For stem rust, 12 (27.2%) showed SR, 2 (4.5%) had ASR, and 30 (68.2%) were susceptible. Bread wheat genotypes M-97-7, M-97-14, M-97-15, N-97-4, and N-97-7 demonstrated promising resistance against both diseases. A strong positive correlation were observed between the APR parameters (FRS, CI, rAUDPC), validating their reliability for assessing quantitative resistance (Hei et al., 2015). However, the correlations between seedling infection types (ITs) and adult plant parameters were non-significant. This finding indicated that APR is genetically independent from all-stage resistance (Singh et al., 2011). The superior performance of certain bread wheat genotypes suggests combinations of non-race-specific APR genes, such as Yr18/Lr34 or Yr46/Lr67, which are known for their durable and pleiotropic effects (Huerta-Espino et al., 2020; Chen, 2020). Consequently, gene pyramiding is highly recommended to develop new bread wheat cultivars with robust and long-lasting resistance. Therefore, reducing reliance on fungicides and mitigating the risk of future epidemics driven by emerging virulent pathogen populations (Singh et al., 2011). References Chen, X. 2020. Pathogens which threaten food security: Puccinia striiformis, the wheat stripe rust pathogen. Food Security, 12(2), pp.239–251. DOI: 10.1007/s12571-020-01016-z Singh, R.P., Huerta-Espino, J., Bhavani, S., Herrera-Foessel, S.A., Singh, D., Singh, P.K., Velu, G., Mason, R.E., Jin, Y., Njau, P. and Crossa, J. 2011. Race non-specific resistance to rust diseases in CIMMYT spring wheats. Euphytica, 179(1), pp.175–186. DOI: 10.1007/s10681-010-0322-9 Huerta-Espino, J., Singh, R.P., Crespo-Herrera, L.A., Villaseñor-Mir, H.E., Rodriguez-Garcia, M.F., Dreisigacker, S., Barcenas-Santana, D. and Lagudah, E. 2020. Adult plant slow rusting genes confer high levels of resistance to rusts in bread wheat cultivars from Mexico. Frontiers in Plant Science, 11, 824. DOI: 10.3389/fpls.2020.00824 Zeng, Q.D., Han, D.J., Wang, Q.L., Yuan, F.P., Wu, J.H., Zhang, L., Liu, D.J. and Jin, S.L. 2014. Stripe rust resistance and genes in Chinese wheat cultivars and breeding lines. Euphytica, 196(2), pp.271-284. DOI: 10.1007/s10681-013-1029-5 عدم وجود مقاومت پایدار در ارقام گندم تجاری، عامل اصلی در بروز همه‌گیری‌های زنگ زرد و زنگ ساقه است که می‌تواند تولید گندم را در مناطق مختلف جهان به شدت تحت تأثیر قرار دهد. این پژوهش با هدف شناسایی منابع مقاومت در مراحل گیاهچهای و گیاه بالغ در میان برخی از ژنوتیپ‌های گندم نان تولید شده در برنامه های ملی به نژادی گندم برای اقلیمهای معتدل و گرم و مرطوب شمال کشور انجام شد. چهل و چهار ژنوتیپ گندم نان (شامل 19 ژنوتیپ از برنامه به نژادی اقلیم معتدل و ۲۵ ژنوتیپ از برنامه به نژادی اقلیم گرم و مرطوب شمال) به همراه شاهدهای حساس، در مراحل گیاهچه‌ای (در گلخانه در کرج) و گیاه بالغ (مزرعه) در دو سال زراعی متوالی (۹۸-۱۳۹۷ و ۹۹-۱۳۹۸) در ایستگاه تحقیقات کشاورزی اردبیل برای واکنش به بیماری های زنگ زرد و ساقه مورد ارزیابی قرار گرفتند تا سازوکار‌های مختلف مقاومت در آنها شناسایی شوند. مقاومت در مرحله گیاه بالغ با استفاده از معیارهای همهگیری بیماری شامل: ضریب آلودگی، شدت نهایی بیماری و مقدار نسبی سطح زیر منحنی پیشرفت بیماری در شرایط مزرعه و در برابر جمعیت‌های محلی ارزیابی شد. همچنین واکنش‌های گیاهچهای در شرایط کنترل‌شده در برابر دو پاتوتیپ زنگ زرد و چهار پاتوتیپ زنگ ساقه در گلخانه انجام شد. نتایج نشان داد که 12 (27/2%)، 20 (45/4%) و 12 (27/2%) ژنوتیپ بهترتیب دارای مقاومت تدریجی، مقاومت گیاهچهای یا تمام‌مرحله‌ای و مقاومت در مرحله گیاه بالغ به زنگ زرد بودند. در مورد زنگ ساقه، 12 ژنوتیپ (27/2%) دارای مقاومت تدریجی، دو ژنوتیپ (4/5%) دارای مقاومت گیاهچهای و30 ژنوتیپ (68%) حساس بودند. یافته‌های این پژوهش طیف وسیعی از واکنشهای مقاومتی را نشان داد. ژنوتیپ‌هایی که در مرحله گیاهچهای نسبت به حداقل یک پاتوتیپ حساس، اما در مرحله گیاه بالغ واکنش‌های نیمه‌مقاوم تا نیمه‌حساس همراه با شدت بیماری پایین را نشان دادند، احتمالاً حامل چندین ژن مقاومت گیاه بالغ یا مقاومت تدریجی هستند. این ژنوتیپ‌ها می‌توانند به‌عنوان منابع ژنتیکی ارزشمند در برنامه‌های به‌نژادی برای تولید ارقام جدید با مقاومت پایدار مورد استفاده قرار گیرند.

https://spj.areeo.ac.ir/article_134886_29794a60f9e64d3cc1db20149fd17021.pdf